EP2693456B1

Movatterモバイル変換

Info

Publication number: EP2693456B1
Application number: EP12178942.4A
Authority: EP
Inventors: Andrea Bianco; Gabriele Valentino De Natale
Original assignee: ABB Technology AG
Current assignee: ABB Technology AG
Priority date: 2012-08-02
Filing date: 2012-08-02
Publication date: 2015-12-16
Anticipated expiration: 2032-08-02
Also published as: WO2014019798A1; EP2693456A1

Description

The present invention relates to a coil actuator for a switching device and to a related method for correcting operation times which are counted by the coil actuator and which are associated to actuations of a switching device, actuations caused by the coil actuator itself.
As known, switching devices used in electrical circuits, such as in low or medium voltage electric circuits, typically circuit breakers, disconnectors and contactors, are devices designed to allow the correct operation of specific parts of the electric circuits in which they are installed, and of the associated electric loads. For the purpose of the present disclosure the term "low voltage" is referred to applications with operating voltages up to 1000V AC/1500V DC, and the term "medium voltage" is referred to applications in the range from 1 kV to some tens of kV, e.g. 50 kV.
Switching devices can be actuated during their operation from an open position to a closed position so as to allow a current flowing therethrough, and from the closed position to the open position so as to interrupt such current flowing.
In particular, the switching devices comprise one or more electrical poles, or phases, each having at least a contact movable between a first position, or coupled position, in which it is coupled to a corresponding fixed contact (switching device in the closed position), and a second position, or separated position, in which it is spaced away from the corresponding fixed contact (switching device in the open position).
A suitable operating mechanism is operatively associated to the movable contacts so as to cause the displacement of such movable contacts between the coupled and separated positions.
Coil-based actuators, hereinafter indicated as "coil actuators", are frequently used in switching devices, for example in mechanical operated switching devices for low or medium voltage circuits; mechanically operated switching have an operating mechanism of the known "stored-energy" type, wherein the energy required for opening the switching device is stored in suitable elastic means, such as springs.
A typical use of a coil actuator is to release mechanical parts of the associated switching device, e.g. corresponding parts of the operating mechanism, so as to open or close the switching device itself, following an opening or a closure command and/or event. Examples of such coil actuators are opening shunt releases, closure shunt releases or undervoltage shunt releases, which are all devices well known in the art.
DocumentWO2009/135519 discloses a device according to the preamble ofclaim 1 and a method according to the preamble ofclaim 10.
Generally, an operation time associated to opening and/or closure actuation of the switching device is measured for various tasks, e.g. to implement a diagnostic function about the reliability of the switching device.
Each measured operation time comprises the activation time of the coil actuator and the time required by the operating mechanism to cause the actuation of the switching device upon the interaction with the coil actuator.
In the state of the art the operation times are measured by means of portable instruments for service tasks, or IEDs ("intelligent electronic devices") with advanced diagnostic functionalities, or electronic protection relays, or dedicated diagnostic and/or monitoring instruments operatively, which are all operatively connected to the switching device.
The use of such additional equipment implies a series of disadvantages, among which: complex wiring and cabling, high installation costs, and encumbrance due to the large volume occupied by the additional equipment.
Furthermore, considering a sequence of actuations of the switching device caused by a coil actuator, the counted operation times associated to the actuations of such sequence are distributed around a desired target operation time for the switching device, generally following a Gaussian statistical distribution.
As known, this undesired effect is mainly due to the dependence of the operation time to be measured to the time required by the operating mechanism to cause the actuation of the switching device. In particular, such required time can widely vary due for instance to production variances, as well as other variables influencing the performance of the operating mechanism, such as degradation of mechanical parts or the environment temperature.
The variance of the measured operation times with respect to the target value is generally not negligible in view for example of the diagnostic functionality and a correct operating of the switching device.
Therefore, at the current state of the art, although known solutions perform in a rather satisfying way, there is still reason and desire for further improvements.
Such desire is fulfilled by a coil actuator for an electric switching device which can be actuated during its operation from an open position to a closed position so as to allow a current flowing therethrough and from said closed position to said open position so as to interrupt such current flowing, said coil actuator being adapted to cause actuations of said switching device, each of said actuations having an operation time associated thereto and said operation time comprising a configurable delay time. The coil actuator comprises electronic means arranged to:

count a first operation time associated to a first actuation of the switching device caused by the coil actuator;
determine a correction time by comparing a target operation time to said counted first operation time;
apply at least an amount of said correction time to the configurable delay time of an operation time associated to at least one subsequent actuation of the switching device caused by the coil actuator and occurring after said first actuation, so as to modify said configurable delay time and reduce the difference between said operation time and said target operation time;
count the corrected operation time associated to said at least one subsequent actuation.

Such desire is also fulfilled by a method for correcting operation times counted by a coil actuator and associated to actuations of a switching device which are caused by said coil actuator, wherein each of said operation times comprises a configurable delay time. The method comprises:

counting a first operation time associated to a first actuation of the switching device (100) caused by the coil actuator;
determining a correction time by comparing a target operation time to said counted first operation time;
applying at least an amount of said correction time to the configurable delay time of an operation time associated to at least one subsequent actuation of the switching device caused by the coil actuator and occurring after said first actuation, so as to modify said configurable delay time and reduce the difference between said operation time and said target operation time;
counting the corrected operation time associated to said at least one subsequent actuation.

Another aspect of the present disclosure is to provide a switching device comprising at least a coil actuator such as the coil actuator defined by the annexed claims and disclosed in the following description; another aspect is to provide a switchgear comprising at least a switching device and/or at least a coil actuator according to the annexed claims and disclosed in the following description.
Further characteristics and advantages will be more apparent from the description of exemplary, but non-exclusive, embodiments of the coil actuator, the related switching device, and the related correction method according to the present disclosure, illustrated in the accompanying drawings, wherein:

figure 1 is a schematic view of a switching device comprising three coil actuators according to the present disclosure;
figure 2 is a schematic view of a first possible coil actuator according to the present disclosure;
figure 3 is a schematic view of the coil actuator offigure 2 operatively connected to a power supply and to a trip circuit supervisor according to the present disclosure;
figure 4 is a plot showing the time dependence of the voltage applied at the input of the coil actuator infigure 2 during its operation;
figure 5 is a schematic view of a second possible coil actuator according to the present disclosure;
figure 6 is a block diagram illustrating a method of correction related to a coil actuator according to the present disclosure;
figure 7 illustrates a first example of implementing a step of the method illustrated infigure 6;
figure 8 illustrates a second example of implementing a step of the method illustrated infigure 7.

It should be noted that in the detailed description that follows, identical or similar components, either from a structural and/or functional point of view, have the same reference numerals, regardless of whether they are shown in different embodiments of the present disclosure; it should also be noted that in order to clearly and concisely describe the present disclosure, the drawings may not necessarily be to scale and certain features of the disclosure may be shown in somewhat schematic form.
With reference to the exemplary embodiments offigures 1-5, acoil actuator 1 according to the present disclosure is adapted to be installed in aswitching device 100, such as for example a low or mediumvoltage circuit breaker 100, comprising at least apole 101 having one or moremovable contacts 102 with associated correspondingfixed contacts 103.Contacts 102 are movable between a coupled position, wherein they are coupled to the correspondingfixed contacts 103, and a separated position wherein they are spaced away from the correspondingfixed contacts 103.
Theswitching device 100 can be actuated during its operation from an open position to a closed position so as to allow a current flowing therethrough and from the closed position to the open position so as to interrupt such current flowing.
In particular, the displacement of themovable contacts 102 from the separated position towards the coupled position allows a current flowing through the coupled movable andfixed contacts 102, 103 (closure actuation of the switching device), and the displacement of themovable contacts 102 from the coupled position towards the separated position causes the interruption of such current flowing (opening actuation of the switching device).
Figure 1 schematically illustrates aswitching device 100 having for example threepoles 101, each comprising amovable contact 102 and a correspondingfixed contact 103; such an embodiment has to be understood only as an illustrative and non limiting example, since the principles and technical solutions introduced in the following description can be applied to switchingdevices 100 having a number ofpoles 101 different with respect to the illustrate one, such as for example aswitching device 100 with asingle pole 101, or twopoles 101, or fourpoles 101.
Anoperating mechanism 104, for example an energy-storedoperating mechanism 104, is operatively connected to themovable contacts 102 so to cause the movement ofsuch contacts 102 between the coupled and separated positions with respect to the correspondingfixed contacts 103, and therefore to cause the actuation of theswitching device 100 between its closed position and its open position.
Thecoil actuator 1 according to the present disclosure is adapted to cause actuations of theswitching device 100 where it is installed.
According to the exemplary embodiments offigures 1-5, thecoil actuator 1 comprises a coil electromagnet 2 arranged to move between a rest position (or released position) and an actuating position (or launched position), wherein the movement from the rest position to the actuating position is suitable to cause an actuation of the switching 100.
In particular, thecoil actuator 1 according to the present disclosure can be installed and used into theswitching device 100 as aclosure actuator 1, wherein the movement of its coil electromagnet 2 from the released to the launched position causes the closure of theswitching device 100, i.e. the actuation of theswitching device 100 itself from the open position to the closed position.
Thecoil actuator 1 according to present disclosure can be installed and used in theswitching device 100 as anopening actuator 1, wherein the movement of its coil electromagnet 2 from the released to the launched position causes the opening of theswitching device 100, i.e. the actuation of theswitching device 100 itself from the closed position to the open position. According to the exemplary embodiment offigure 2 and to the exemplary embodiment offigure 5, the coil electromagnet 2 of thecoil actuator 1 comprises one or more parts 3 which are arranged to move, during the movement of the coil electromagnet 2 itself from the released to the launched position, so as to interact with one or more corresponding parts of theswitching device 100; such operative interaction between the movable parts 3 of the coil electromagnet 2 and the corresponding parts of theswitching device 100 causes the actuation of theswitching device 100 itself.
Thecoil actuator 1 according to the present disclosure comprises for example a case which houses the coil electromagnet 2 and which is configured for allowing a part 3 of the coil electromagnet 2 itself, e.g. an anchor or plunger 3, to move between a first stable position, or retracted position, wherein it is retracted into the case (coil electromagnet 2 is in the released, or rest, position), and a second stable position, or launched position, wherein at least a portion of the movable part 3 is launched outside the case (coil electromagnet 2 is in the launched, or actuating, position).
The movable part 3 of the coil electromagnet 2 is arranged to release, through its movement from the retracted to the launched position, one or more corresponding mechanical parts of theoperating mechanism 104 of theswitching device 100, so as to cause the actuation of theswitching device 100 itself.
Theopening actuator 1 according to the present disclosure is installed into theswitching device 100 in such a way that the interaction between the movable parts 3 of its electromagnet 2 and the corresponding parts of theswitching device 100, e.g. parts of theoperating mechanism 104, causes the opening of theswitching device 100, i.e. the actuation of theswitching device 100 itself from its closed to position to its open position.
Theclosure actuator 1 according to the present disclosure is installed into theswitching device 100 in such a way that the interaction between the movable parts 3 of its electromagnet 2 and the corresponding parts of theswitching device 100, e.g. parts of theoperating mechanism 104, causes the closure of theswitching device 100, i.e. the actuation of theswitching device 100 itself from its open position to its closed position.
For example, theswitching device 100 illustrated infigure 1 comprises at least an opening actuator 1a and a closure actuator 1b.
With reference to the exemplary embodiments offigures 2 and5, thecoil actuator 1 according to the present disclosure compriseselectronic means 1000, embedded inside thecoil actuator 1 itself.
Theelectronic means 1000 are advantageously arranged to count an operation time T_operation associated to each actuation of theswitching device 100 caused by thecoil actuator 1 itself. The counted operation time T_operation is indicative of the duration of the associated actuation of theswitching device 100, since that the operation time T_operation comprises:

an activation time of the coil actuator 1 (i.e. the time elapsed between a detection by thecoil actuator 1 of an intervention request, or need, and the end of the consequent movement of the coil electromagnet 2, from the rest to the actuating position); and
a time required by theoperating mechanism 104 to cause the actuation of theswitching device 100, upon the intervention on it of thecoil actuator 1.

It is to be set forth that if thecoil actuator 1 is installed and used in theswitching device 100 as anopening actuator 1, the operation time T_operation to be counted is an opening operation time. In that case the counted opening operation time T_operation is indicative of the duration of the actuation of theswitching device 100 from the closed to the open position, since that it comprises the time required by theoperating mechanism 104 to move thecontacts 102 from the coupled to the separated position with respect to the correspondingfixed contacts 103.
If thecoil actuator 1 is installed and used in theswitching device 100 as aclosure actuator 1, the operation time T_operation to be counted is a closure operation time. In that case the counted operation time T_operation is indicative of the duration of the actuation of theswitching device 100 from the open to the closed position, since that it comprises the time required by theoperating mechanism 104 to move thecontacts 102 from the separated to the coupled position with respect to the corresponding fixedcontacts 103.
For example, in theswitching device 100 illustrated infigure 1 the opening actuator 1a and the closure actuator 1b comprise correspondingelectronic means 1000 which are arranged to count opening operation times and the closure operation times of the illustratedswitching device 100, respectively.
Preferably, each operation time T_operation associated to a corresponding actuation of theswitching device 100 comprises a configurable delay time T_delay. The delay time T_delay is set to have operation times T_operation according to a required target operation time T_target of theswitching device 100.
In particular, the target operation time T_target may vary due to different normatives or to different typologies of switchingdevice 100 where thecoil actuator 1 could be installed; the operation times T_operation to be counted are accordingly adapted to the required target operation time T_target through a suitable initial setting of their configurable delay time T_delay.
For instance, the required target opening operation time T_target for a mechanically operated mediumvoltage circuit breaker 100 is generally comprised in the range between 50 and 73 ms, while the required target closure operation time T_target is typically comprised in the range between 50 and 70 ms.
Preferably, theelectronic means 1000 are arranged to receive and store such delay time T_delay as a configurable parameter.
Preferably, theelectronic means 1000 are arranged to associate the configurable delay time T_delay to the activation time of thecoil actuator 1, for example introducing such delay T_delay between the detection by thecoil actuator 1 of the intervention request, or need, and the consequent electrical driving of the coil electromagnet 2 (to cause the movement thereof from the rest to the actuating position).
With reference to the exemplary embodiment offigures 6-8, the present disclosure is also related to amethod 700 for advantageously correcting the operation times T_operation counted by thecoil actuator 1 and associated to the actuations of theswitching device 100 which are caused by thecoil actuator 1 itself.
The electronic means 1000 of thecoil actuator 1 are arranged to carry out themethod 700 according to the present disclosure.
In particular, according to the exemplary embodiment offigure 6, theelectronic means 1000 are arranged to:

count a first operation time T_operation1 associated to a first actuation of theswitching device 100 caused by the coil actuator 1 (step 600 of the method 700);
determine a correction time T_correction by using the counted operation time T_operation1 (step 601 of the method 700);
use the correction time T_correction to correct an operation time T_operation2, T_operation3,...T_operationN associated to at least one subsequent actuation of theswitching device 100 caused by thecoil actuator 1 and occurring after the first actuation (step 602 of the method 700);
count the corrected operation time T_operation2-T_operationN associated to said at least one subsequent actuation (step 603 of the method 700).

The determined correction time T_correction is advantageously suitable to at least reduce the difference between the target operation time T_target required for theswitching device 100 and the counted corrected operation time T_operation2-T_operationN.
Preferably, theelectronic means 1000 are arranged to receive and store the target operation time T_target for theswitching device 100 as a configurable parameter.
Preferably, theelectronic means 1000 are arranged to determine the correction time T_correction by comparing the target operation time T_target to the counted operation time T_operation1 associated to the first actuation of theswitching device 100. Accordingly thestep 601 of themethod 700 comprises determining the correction time T_correction by comparing the target operation time T_target to the counted operation time T_operation1.
For example, the correction time T_correction is given by the difference between the target operation time T_target and the counted operation time T_operation1. In that case, the correction time T_correction could be positive or negate, depending if the counted operation time T_operation1 is greater or smaller than the target operation time T_target.
According to the exemplary embodiment offigure 6, theelectronic means 1000 of thecoil actuator 1 are arranged to apply at least an amount of the correction time T_correction to the configurable delay time T_delay of the operation time T_operation2-T_operationN which is associated to said at least one subsequent actuation of theswitching device 100 occurring after the first actuation.
Accordingly thestep 602 of themethod 700 comprises thestep 605 of applying at least an amount of the correction time T_correction to the configurable delay time T_delay of the operation time T_operation2-T_operationN associated to said at least one subsequent actuation.
In this way, the configurable delay time T_delay of such operation time T_operation2-T_operationN is modified by applying thereto at least an amount of the correction time T_correction. Such modification is the correction suitable for at least reducing the difference between the target operation time T_target and the counted corrected operation time T_operation2-T_operationN.
According to the exemplary embodiment offigure 7 and considering the first actuation and a second subsequent actuation of theswitching device 100, theelectronic means 1000 are arranged to use the determined correction time T_correction to correct the operation time T_operation2 associated to such second actuation. In particular, theelectronic means 1000 are arranged to apply the overall determined correction time T_correction to the configurable delay time T_delay of the operation time T_operation2 (method step 605 illustrated infigure 7).
Preferably, the overall correction T_correction is directly added the configurable delay time T_delay of the operation time T_operation2.
According to the exemplary embodiment offigure 8 and considering the first actuation and a plurality of subsequent actuations of theswitching device 100, theelectronic means 1000 are arranged to:

divide the determined correction time T_correction into a plurality of addends T_add1, T_add2,....T_addN-1 (method step 604 illustrated infigure 8); and
apply each addend T_add1, T_add2,.... T_addN-1 to the configurable delay time T_delay of a corresponding operation time T_operation2, T_operation3,...T_operationN which is associated to an actuation of said plurality of subsequent actuations (method steps 605₁, 605₂,...605_N illustrated infigure 8).

For example, it is considered a sequence of four consecutive actuations of theswitching device 100 caused by thecoil actuator 1. Basing on the counted operation time T_operation1 associated to the first actuation of the sequence, theelectronic means 1000 firstly determine a correction time T_correction, having for instance a value of 6 ms.
Then theelectronic means 1000 apply:

2 ms (first addend T_add1) to the configurable delay time T_delay of the operation time T_operation2 associated to the second actuation of the sequence, occurring after the first actuation;
2 ms (second addend T_add2) to the configurable delay time T_delay of the operation time T_operation3 associated to the third actuation of the sequence, occurring after the second actuation; and
2 ms (third addend T_add3) to the configurable delay time T_delay of the fourth actuation of the sequence, occurring after the third actuation.

With reference to the exemplary embodiment offigure 2 and to the exemplary embodiment offigure 5, theelectronic means 1000 of thecoil actuator 1 according to the present disclosure comprise:

detection means 11 arranged to detect a first event, or launch event, which is indicative of a request, or need, for an actuation of theswitching device 100;
driving means 10 operatively associated to the detection means 11 and connected to the coil electromagnet 2 of thecoil actuator 1.

The driving means 10 are arranged to electrically drive the coil electromagnet 2 to cause at least the movement thereof from the released position to the launched position upon the detection of the launch event by the detection means 11. The detection means 11 of thecoil actuator 1 are arranged to detect also a second event which is indicative of the end of the actuation of theswitching device 100, wherein such actuation is caused by thecoil actuator 1 itself upon the detection of the launch event and the consequently movement of its coil electromagnet 2.
The electronic means 1000 of thecoil actuator 1 further comprise counting means 20 which are operatively associated to the detection means 11 and are arranged to count the operation time T_operation associated to each actuation of theswitching device 100 caused by thecoil actuator 1 itself upon the detection of a launch event.
Again it is set forth that when thecoil actuator 1 is conceived and used in theswitching device 100 as anopening actuator 1, the counted operation time T_operation is an opening operation time associated to the actuation of theswitching device 100 from the closed to the open position. When instead thecoil actuator 1 is conceived and used in theswitching device 100 as aclosure actuator 1, the counted operation time T_operation is a closure operation time associated to the actuation of theswitching device 100 from the open to the closed position.
The counting means 20 are arranged to start counting the operation time T_operation when the launch event is detected by the detection means 11, and to stop such counting when the second event is detected by the detection means 11. Therefore, the detection of the launch event and the detection of the second event trigger the start and the end, respectively, of the counting performed by the counting means 20.
Preferably the driving means 10 are arranged to apply the configurable delay time T_delay of the operation time T_operation to be counted between the detection of the launch event and the consequent electrical driving of the coil electromagnet 2.
In particular, considering the implementation of thestep 605 of themethod 700, the driving means 10 are arranged to apply the configurable delay time T_delay as modified by applying thereto at least an amount of the previously determined correction time T_correction, in such a way to correct the operation time T_operation to be actually counted.
Preferably, theelectronic means 1000 of thecoil actuator 1 according to the present disclosure comprise comparingmeans 21 operatively associated to the counting means 20 and arranged to compare the counted operation time T_operation with a temporal acceptance range T_range which is indicative of an acceptable value for theswitching device 100.
Preferably, the comparingmeans 21 are arranged to receive and store the acceptance range T_range as a configurable parameter.
Preferably, thecoil actuator 1 is arranged to cause the generation of an alarm signaling, e.g. the generation of at least an alarm signal and/or indication, when the counted operation time T_operation exceeds the associated temporal range T_range.
Thecoil actuator 1 according to the exemplary embodiment offigure 2 can be installed and used in theswitching device 100 as a shunt opening release 1 (such as for example the coil actuator 1a infigure 1) configured for opening theswitching device 100 following an opening command and/or signal, or alternatively can be installed and used in theswitching device 100 as a shunt closure actuator 1 (such as for example the coil actuator 1b infigure 1) configured for closing theswitching device 100 following a closure command and/or signal.
The opening and closure commands and/or signals can be generated automatically by suitable means or by an operator, and can be generated inside theswitching device 100 or received by remote. For example, an opening, or trip, command can be generated by a protection device installed into theswitching device 100 upon the detection of an electrical fault.
The driving means 10 of thecoil actuator 1 according to the embodiment offigure 2 are arranged to electrically drive the coil electromagnet 2 so as to hold it in the launched position and so as to allow the return thereof from the launched position to the release position upon the detection of the second event, or release event, by the detection means 11.
Preferably, such driving means 10 comprise apower input circuit 12 arranged to be operatively connected to and receive an input voltage V_in from at least a power source, e.g. a power associated to theswitching device 100 and/or to the electric circuit into which theswitching device 100 itself is installed, for example apower line 200 associated to the switching device 100 (seefigure 3).
Thepower input circuit 12 is arranged to use the received input voltage V_in to provide a suitable power supply to several components and/or elements of thecoil actuator 1, in particular to itselectronic means 1000.
For instance, thepower input circuit 12 may comprise one or more input filters and a rectifier to convert the AC voltage received from thepower line 200 to a DC input voltage.
With reference tofigures 2-4, the detection means 11 are arranged to continuously sense a voltage indicative of the input voltage V_in, i.e. to sense directly the voltage V_in applied to thepower input circuit 12, or indirectly through a voltage generated in thecoil actuator 1 and depending on such input voltage V_in.
In particular, the detection means 11 are arranged to detect, by means of the sensed voltage, a first threshold value, or launch threshold value V_th__launch, and a second threshold value, or release threshold value V_{th_release}, of the input voltage V_in, wherein the launch threshold value V_{th_launch} is preferably higher than the release threshold value V_{th_release}.
The driving means 10 are operatively associated to the detection means 11 so as to electrically drive the coil electromagnet 2 for moving and holding the coil electromagnet 2 itself in the launched position upon the detection of the launch threshold value V_th__launch. The launch and hold operations of the coil electromagnet 2 are executed by the driving means 10 using the power drawn from the input voltage V_in, having a value above the launch threshold value V_{th_launch}.
The driving means 10 are operatively associated to the detection means 11 so as to at least reduce, preferably interrupt, the electrical driving of the coil electromagnet 2 for allowing the return thereof from the launched position to the release position, upon the detection of the release threshold value V_{th_release} by the detection means 11.
The detection of the launch threshold value V_th__launch and the detection of the release threshold value V_{th_relesase} are the launch event and the release event which trigger the start and the end, respectively, of the counting performed by the counting means 20 (see the plot illustrated as an example infigure 4).
In the exemplary embodiment offigure 2, thecoil actuator 1 comprises a single coil electromagnet 2, i.e. a coil electromagnet 2 having a singleelectromagnetic coil 4 operatively associated to the movable part 3 and electrically connected to the driving means 10; in particular, the driving means 10 are arranged to: generate a launch current I_L flowing through theelectromagnetic coil 4 so as to generate a magnetic force suitable for moving the part 3 from the retracted to the launched position; and consequently reduce and maintain the launch current I_L at a holding current I_H suitable for holding the movable part 3 in the launched position.
The driving means 10 illustrated infigure 2 advantageously comprise afirst control unit 31 and asecond control unit 32, wherein thesecond control unit 32 is suitable for controlling the current flowing through the single coil electromagnet 2 and thefirst control unit 31 is operatively connected to thesecond control unit 32 for setting the current which has to flow through the single coil electromagnet 2. By using the single coil electromagnet 2 and the associated first andsecond control units 31, 32, the number of electromagnetic variables is reduced, therefore reducing the manufacturing and handling costs.
Thefirst control unit 31 can be any electronic device suitable for receiving and executing software instructions, and for receiving and generating output data and/or signals through a plurality of input and/or output ports. For example, thecontroller 31 may be amicrocontroller 31, such as the MSP430 microprocessor produced and made available in commerce by Texas Instruments®.
The driving means 10 comprise apower circuit 37 operatively connected to the single coil electromagnet 2 and to thesecond control unit 32 so as to generate the current flowing through the single coil electromagnet 2 according to the control performed by thesecond control unit 32. In the embodiment offigure 2 thesecond control unit 32 is for example a PWM ("Pulse width modulation")controller 32 and the associatedpower circuit 37 comprises: anelectronic power switch 40 to electrically drive the single coil electromagnet 2, such as a power MOSFET ("metal-oxide-semiconductor field-effect transistor"); a freewheelingdiode 41; and asense resistor 43 for measuring the current flowing through the single coil electromagnet 2. In practice, thePWM controller 32 is configured for driving thepower switch 40 through aPWM signal 400 so as to regulate the current flowing through the single coil electromagnet 2 according to the settings received from thecontrol unit 31.
Thepower input circuit 12 is operatively connected to thepower circuit 37, thefirst control unit 31 and thesecond control unit 32 to provide them the power required to operate; preferably, apower converter 35 is provided to convert and adapt the voltage outputted by thepower input circuit 12 into values suitable for supplying the first andsecond controllers 31, 32.
Thecontroller 31 stores instructions which, when executed by thecontroller 31 itself, carry out themethod 700 according to the present disclosure. In particular, the stored instructions are suitable to implement all the functionality blocks required to carry out the method, among them the detection means 11 and the counting means 20. If provided, the stored instructions are also suitable to implement the comparingmeans 21.
In particular, thecontroller 31 is arranged to receive and store configurable parameters, for example through a software download operation, comprising at least the launch and release voltage threshold values V_{th_launch}, V_{th_release} of the detection means 11, the target operation time T_target, the configurable delay time T_delay and the temporal range T_range of the comparingmeans 21.
Ajumper 39 can be operatively connected to thecontroller 31 to allow the resetting of at least a stored configurable parameter.
In order to implement the detection means 11, aninput port 302 of thecontroller 31 is associated to the implemented detection means 11 and is electrically connected at the electrical point where the input voltage V_in is applied to the power input circuit 12 (as shown schematically infigure 2), so as to continuously and directly sense such input voltage V_in. Alternatively to the exemplary embodiment offigure 2, the coil electromagnet 2 may comprise two electromagnetic coils, or windings, operatively associated to the movable part 3, wherein the driving means 10 connected to such coil electromagnet 2 would be arranged to selectively energize the two coils for moving the part 3 from the retracted to the launched position and for holding such movable part 3 in the launched position, until a release event is detected by the detection means 11.
With reference tofigure 3, thepower input circuit 12 of theshunt release 1 illustrated infigure 2 is operatively connected to thepower source 200 throughcables 13 and at least acontact 201 is placed along the power delivery path from thepower source 200 to thepower input circuit 12 so as to realize or interrupt such delivery path according to its closure or opening, respectively.
In particular, if thecoil actuator 1 offigure 2 is installed and used into theswitching device 100 as an open shunt release 1 (such as for example the actuator 1a infigure 1), the closure of thecontact 201 is driven by an opening command and/or signal 202. If thecoil actuator 1 offigure 2 is installed and used into theswitching device 100 as a closure shunt release 1 (such as for example the actuator 1b infigure 1), the closure of thecontact 201 is driven by a closure command and/or signal 202.
For instance, thecontact 201 may be a contact of a protection relay, closed upon the occurrence of a fault event detected by the protection device itself, or may be a button actuable by an operator.
The electrical connection between thepower input circuit 12 and thepower supply 200 through the closure of thecontact 201 causes the rising of the input voltage V_in above the launch threshold value V_{th_launch}, in such a way that the driving means 10 are supplied with the power required to perform the launch and hold operations of the coil electromagnet 2.
The launch operation of the coil electromagnet 2 causes the opening of theswitching device 100 if thecoil actuator 1 is installed and used in theswitching device 100 as ashunt opening release 1, or causes the closure of theswitching device 100 ifsuch coil actuator 1 is installed and used in theswitching device 100 as ashunt closure release 1.
Accordingly, the counting means 20 starts counting the operation time T_operation.
Placed along the power delivery path realized by the closure of thecontact 201 there is also at least anauxiliary contact 203 which is operatively connected to one or moremovable contacts 102 of theswitching device 100 so as to move between an open operative status and a closed operative status according to the movement of thecontacts 102.
Theauxiliary contact 203 is suitable for interrupting the associated delivery path when it moves from its closed to its open status. In particular, if thecoil actuator 1 offigure 3 is installed and used in theswitching device 100 as ashunt opening release 1, theauxiliary contact 203 is operatively connected to the correspondingmovable contacts 102 so as to be in its closed status while theswitching device 100 is in its closed position, and to reach its open status at the end of the opening operation of theswitching device 100 caused by theshunt opening release 1 itself, i.e. when themovable contacts 102 reach their separated position with respect to the corresponding fixedcontacts 103.
If thecoil actuator 1 offigure 3 is installed and used in theswitching device 100 as ashunt closure release 1, theauxiliary contact 203 is operatively connected to the correspondingmovable contacts 102 so as to be in the closed status while theswitching device 100 is in its open position, and to reach its open status at the end of the closure of theswitching device 100 caused by theshunt closure release 1, i.e. when themovable contacts 102 reach their coupled position with respect to the corresponding fixedcontacts 103.
With reference to the exemplary embodiment offigure 5, thecoil actuator 1 according to the present disclosure can be conceived and installed into the associatedswitching device 100 to operate as ashunt undervoltage release 1, i.e. to intervene for opening and/or theswitching device 100 upon the detection of an undervoltage condition. For example, theswitching device 100 infigure 1 comprises ashunt undervoltage release 1c.
According to the exemplary embodiment offigure 5, the driving means 10 of theelectronic means 1000 embedded in theundervoltage shunt release 1 are operatively connected to at least a power source (depicted infigure 5 by the block indicated with the numeral reference 500) that is associated to theswitching device 100 and/or to the electric circuit into whichsuch switching device 100 is installed. In particular, theundervoltage shunt release 1 is connected to thepower source 500 so as to receive therefrom the power required to hold the coil electromagnet 2 in its released (or rest) position, e.g. the power required to keep the movable part 3 of the coil electromagnet in the retracted position against a force generated by compressed elastic means.
The detection means 11 of theelectronic means 1000 embedded in theundervoltage release 1 are arranged to detect a condition, or event, indicative of the occurrence of the undervoltage condition. For instance, the detection means 11 are arranged to:

continuously sense a voltage associated to thepower source 500, i.e. to sense directly the supply voltage V_supply of thepower source 500 or indirectly through a voltage generated in theshunt release 1 and depending on such voltage V_supply;
detect the undervoltage condition, by means of the sensed voltage, when the supply voltage V_supply falls below a predetermined undervoltage threshold value.

The driving means 10 are arranged to at least reduce, preferably interrupt, the energizing of the coil electromagnet 2 so as to cause the movement of the part 3 from the retracted to the launched position upon the detection of the undervoltage condition.
The detection of the undervoltage condition by the detection means 11 is the launch event that triggers the start of the counting of the opening operation time T_operation by means of the counting means 20 provided in theelectronic means 1000.
The detection means 11 are also arranged to detect the event indicative of the end of the opening of theswitching device 100, opening operation caused by theshunt undervoltage release 1; such detection is the event that triggers the end of the counting of the opening operation time T_operation.
For example, the detection means 11 infigure 5 are arranged to detect anelectrical signal 501 suitable for signaling the end of the opening operation of theswitching device 100 caused by an undervoltage condition, such as asignal 501 generated by the closure of acontact 302 operatively connected to one or more of themovable contacts 102 of theswitching device 100 so as to close when such one or moremovable contacts 102 reach their separated position with respect to the corresponding fixedcontacts 103.
Preferably the driving means 10 are arranged to apply the configurable delay time T_delay of the operation time T_operation to be counted, between the detection of the undervoltage condition and the consequent electrical driving of the coil electromagnet 2 (to cause the movement of the part 3 from the retracted to the launched position).
In particular, considering the implementation of thestep 605 of themethod 700, the driving means 10 are arranged to apply the configurable delay time T_delay as modified by applying thereto at least an amount of the previously determined correction time T_correction, in such a way to correct the operation time T_operation to be counted.
Theundervoltage shunt release 100 illustrated infigure 5 further comprises: the comparingmeans 21 for comparing the counted opening operation time T_operation with the temporal range T_range; and alarm generating means 510 operatively associated to the comparingmeans 21 and arranged to generate an alarm signal and/or indication if the counted opening operation time T_operation exceeds the temporal range T_range.
Thecoil actuator 1 according to the present disclosure is arranged to provide a continuous power supply to itselectronic means 1000, at least for a time required to implement the various steps of themethod 700 according to the present disclosure.
If the comparingmeans 21 are provided, thecoil actuator 1 is also arranged to provide a continuous power supply to such comparingmeans 21, at least for a time required to complete the comparison operation.
For example, theundervoltage shunt release 1 according to the embodiment offigure 5 comprises at least abackup capacitor 511 suitable for storing energy drawn by the V_supply applied to theundervoltage shunt release 1 and connected at least to theelectronic means 1000 so as to release the stored energy thereto, starting from the occurrence of the undervoltage condition.
It is to be set forth that the backup capacitor 511 (or alternatively other suitable energy storage means) is also connected to: the detection means 11, so as to provide them the power required to detect thesignal 501 indicative of the end of the opening operation of theswitching device 100, even during the undervoltage condition; and the alarm generating means 510, so as to provide them the power required to generate the alarm signaling, even during the undervoltage condition.
According to a first exemplary solution, thecoil actuator 1 according to the embodiment offigure 2 can comprise a backup capacitor connected to thepower input circuit 12 so as to be charged while the input voltage V_in is applied to thecoil actuator 1 itself by thepower source 200. Advantageously, the backup capacitor may be the smoothing capacitor used in thepower input circuit 12 to rectify the AC voltage received from thepower line 200 to a DC input voltage.
With reference tofigure 3, at the opening of theauxiliary contact 203 the application of the input voltage V_in to the power input circuit 2 of thecoil actuator 1 stops, and the backup capacitor releases the stored energy to supply theelectronic means 1000.
According to a second exemplary solution, theelectronic means 1000 of thecoil actuator 1 according to the embodiment offigure 2 are operatively connected to thepower input circuit 12 of the driving means 10. Thepower input circuit 12 is in turn arranged to be operatively connected to the associatedpower source 200 so as to receive therefrom the power required to continuously supply at least a minimum input voltage V_{in_min} to theelectronic means 1000; the minimum input voltage V_{in_min} is suitable for providing theelectronic means 1000 with the power required to complete at least the required steps of themethod 700.
With reference tofigures 2-3, thecoil actuator 1 is advantageously arranged to be operatively connected atrip circuit supervisor 150 installed into theswitching device 100.
Thetrip circuit supervisor 150 is arranged to check the integrity of the coil electromagnet 2, e.g. the integrity of theelectromagnetic coil 4 in thecoil actuator 1 illustratedfigure 2, and of the driving means 10 associated thereto (coil supervision and feedback routine). For example, thetrip circuit supervisor 150 may be a supervision relay of the type well known in the art, and therefore not further described herein.
According to the exemplary embodiment offigure 2, thepower input circuit 12 of thecoil actuator 1 is arranged to be operatively connected to thetrip circuit supervisor 150 so as to continuously receive, through suchtrip circuit supervisor 150, the power required to supply the minimum input voltage V_{in_min} to theelectronic means 1000.
For example, thepower input circuit 102 infigure 2 provides, through thetrip circuit supervisor 150, the minimum input voltage V_{in_min} to thefirst control unit 31, thePWM controller 32, and thepower circuit 37. In practice, the input minimum voltage V_{in_min} is suitable to supply the minimum power required from thecoil actuator 1 to work and perform its main functionalities.
With reference tofigure 3, thetrip circuit supervisor 150 is placed along a power delivery path from thepower source 200 to thepower input circuit 12 of thecoil actuator 1, wherein such delivery path is parallel with respect to the power delivery path comprising thecontact 201 and theauxiliary contact 203. In this way, when thecontact 201 or theauxiliary contact 203 interrupts the associated power delivery path, thecoil actuator 1 remains powered to work through thetrip circuit supervisor 150.
The detection means 11 of thecoil actuator 1 according to such embodiment are also arranged to detect the minimum input voltage V_{in_min} and the driving means 10 are arranged to electrically drive the coil electromagnet 2 to generate a coil supervisor current I_cs flowing through such coil electromagnet 2 when the input voltage V_in is detected to be in the range comprised between the minimum input voltage V_{in_min} and the release threshold value V_{th_release}. The coil supervisor current I_cs is lower than the currents generated by the driving means 10 to perform the launch and hold operations of the coil electromagnet 2; for example, the supervisor current I_cs is lower than the launch current I_L and the hold current I_H flowing through theelectromagnetic coil 4 of thecoil actuator 1 illustrated infigure 2.
The current I_tc flowing through thetrip circuit supervisor 150 depends on the supervisor current I_cs flowing through the coil electromagnet 2; the driving means 10 are arranged to: monitor the current I_cs or at least a parameter associated to such current I_cs; check the integrity of the coil electromagnet 2 basing on such monitoring of the supervisor current I_cs; at least reduce, preferably interrupt, the current I_cs upon the checking of a failure in the coil electromagnet 2.
Thetrip circuit supervisor 150 is configured for: sensing the current I_tc flowing therethrough; detecting the reduction of the such current I_ts below a first predetermined threshold, wherein the reduction of the current I_ts is due to the reduction of the supervisor current I_cs; and generating an alarm signaling 151 upon such detection.
In the exemplary embodiment offigure 2 aninput port 300 of thecontroller 31 is operatively connected to theoutput 301 of thePWM controller 32 from which thePWM signal 400 is sent to theMOSFET 40; for example, alow pass filter 38 is used to convert the PWM signal 400 into a voltage suitable for being measured by thecontroller 31.
Thecontroller 31 measures the duty cycle "D" of thePWM signal 400, such duty cycle D depending on the input voltage V_in, the current set by thecontroller 31 and the coil impedance of the single coil electromagnet 2 (i.e. the electrical impedance associated to electromagnetic coil 4).
Therefore, the measurement of the duty cycle D provides an indication on the integrity of the single coil electromagnet 2. In particular, thecontroller 31 is configured for comparing the measured duty cycle D to a predetermined acceptance range, preferably a configurable acceptance range, and for changing the current settings sent to thePWM controller 32 to at least reduce, preferably interrupt, the current I_cs flowing through the single coil electromagnet 2 when the measured duty cycle D exceeds the acceptance range.
The current I_tc is therefore reduced so as to activate the alarm signaling 151 of thetrip circuit supervisor 150. In particular, the current I_tc flowing through thetrip circuit supervisor 150 can be calculated as follows: $Itc = Ics \cdot D + Iq,$

wherein Iq is a quiescent current, i.e. the current needed by thecoil actuator 1 to stay active and work.
Hence, if the supervision current I_cs is interrupted by thecontroller 31 due to a failure in the single coil electromagnet 2, the current I_tc is reduced to the quiescent current Iq which has a value below the set first predetermined threshold for activating the alarm signaling 151. According to the exemplary embodiment offigure 2, the comparingmeans 11 and the driving means 10 of thecoil actuator 1 are operatively associated each other (in particular in thecoil actuator 1 offigure 2 are both implemented by the controller 31), and the driving means 10 are advantageously arranged to at least reduce, preferably interrupt, the supervisor current I_cs when the comparingmeans 11 detect that the counted operation time T_operation exceeds the temporal range T_range of the comparingmeans 21.
In this way the supervisor current I_cs is reduced by the driving means 10 so as the current I_tc flowing through thetrip circuit supervisor 150 falls below the first predetermined threshold. In practice, such reduction of the supervisor current I_cs simulates the detection of a failure in the coil electromagnet 2 and consequently activates the alarm signaling 151 already provided in thetrip circuit supervisor 150.
Alternatively, theshunt trip supervisor 150 may be configured for discriminating between a first condition wherein a fault occurs in the supervised coil electromagnet 2 and a second condition wherein the counted operation time T_operation exceeds the temporal range T_range.
In this way, theshunt trip supervisor 150 can be arranged to generate two different alarm signaling, one indicative of the first condition and the other of the second condition. For example, the driving means 10 can be arranged to reduce the supervisor current I_cs so as the current I_tc flowing through thetrip circuit supervisor 150 falls below a second predetermined threshold, different with respect to the first threshold, when the comparingmeans 11 detect that the counted operation time T_operation exceeds the temporal range T_range of the detection means 11.
In particular, if such second threshold is set above the first threshold, theshunt trip supervisor 150 is arranged to detect when the current I_tc which has fallen below the second threshold also falls below the first threshold; if the current I_tc falls below also to the first threshold, thetrip circuit supervisor 150 is arranged to generate the alarm signaling 151 indicative of a fault in the supervised coil electromagnet 2. If the current I_tc does not fall below also to the first threshold, thetrip circuit supervisor 150 is arranged to generate an alarm signaling, different to the above mentioned alarm signaling 151, which is dedicate for signaling the exceeding of the temporal range T_range.
If the second threshold is set below the first threshold, theshunt trip supervisor 150 is arranged to detect when the current I_tc which has fallen below the first threshold also falls below the second threshold; if the current I_tc falls below also the second threshold, thetrip circuit supervisor 150 is arranged to generate an alarm signaling indicative of the exceeding of the temporal range T_range. If the current I_tc does not fall below also to the second threshold, thetrip circuit supervisor 150 is arranged to generate the alarm signaling 151 indicative of a fault in the supervised coil electromagnet 2.
In practice, it has been seen how thecoil actuator 1, and therelated switching device 100 andmethod 700 according to the present disclosure allow achieving the intended object offering some improvements over known solutions.
In particular, thecoil actuator 1 is arranged to count by itself the operation times T_operation associated to the actuations of theswitching device 100, therefore providing an easy and economical solution that does not require other additional or external equipments connected to theswitching device 100. In this way, additional and complex cabling and wiring, extra-costs, and encumbrance into theswitching device 100 are avoided.
Furthermore, the disclosed method 700 (carried out by theelectronic means 1000 of the coil actuator 1) is suitable to correct the operation times T_operation associated to the actuations of the switching device caused by thecoil actuator 1, in such a way as the counted corrected operation times T_operation remain all close to the required target operation time T_target of theswitching device 100, despite of the variations manly introduced by the operation of theoperating mechanism 104.
In this way, the operative live of theswitching device 100 is improved because all the operations/functionalities which are associated to theswitching device 100 and synchronized to the counted operation time T_operation can occur more correctly about at the required target time T_target.
Thecorrection method 700 also improves the adaptability of thecoil actuator 1 todifferent switching devices 100, having the same required target operation time T_target but different times required by theiroperating mechanisms 104 to actuate the switching device themselves. In that case, themethod 700 automatically corrects the operation times T_operation to remain close to the target operation time T_target, despite of the time difference between the times required by theactuating mechanism 104 of the first andsecond switching devices 100. Furthermore, atrip circuit supervisor 150 can be advantageously connected to thecoil actuator 1 in such a way that, after theauxiliary contact 103 opens, thecoil actuator 1 remains powered to work.
In particular, thecoil actuator 1 may be configured for activating the alarm signaling 151 already provided in thetrip circuit supervisor 150 for signaling failures in the associated electromagnetic coil 2, so as to signal also undesired conditions of unduly operation long times for closing or opening theswitching device 100.
Such results are achieved thanks to a solution which in principle makes thecoil actuator 1 and therelated switching device 100 according to the present disclosure easy to be used in connection with a switchgear. Hence, the present disclosure also encompasses a switchgear comprising at least aswitching device 100 and/or at least acoil actuator 1 according to the present disclosure.
For example, alternatively to the exemplary embodiment offigure 2 thecontroller 31 may be arranged to directly generate an alarm signaling upon the detection of a counted operation time T_operation exceeding the predetermined temporal range T_range.
Further it is to be understood that the functional blocks in thecoil actuator 1 according to present disclosure, i.e. the driving means 10, the counting means 20, the detection means 11, and the comparingmeans 21, may be all implemented in a single electronic unit through the execution of suitable instructions, or alternatively one or more of such functional block may be implemented by dedicated electronic means and/or units suitably connected each other. For example, the counting means 20 may be implemented by adigital counter 20 triggered by the detection means 11, which in turn may be implemented for example by an electronic circuit comprising a comparator.
Although thecontroller 31 has been indicated to be for example a microprocessor,such controller 31 can also be a microcomputer, a minicomputer, a digital signal processor (DSP), an optical computer, a complex instruction set computer, an application specific integrated circuit, a reduced instruction set computer, an analog computer, a digital computer, a solid-state computer, a single-board computer, or a combination of any of theses.
Further, instructions, data, signals and parameters can be delivered to thecontroller 31 via electronic data carts, manual selection and control, electromagnetic radiation, communication buses, and generally through any suitable electronic or electrical transfer.

Claims

A coil actuator (1) for an electric switching device (100) which can be actuated during its operation from an open position to a closed position so as to allow a current flowing therethrough and from said closed position to said open position so as to interrupt such current flowing, said coil actuator (1) being adapted to cause actuations of said switching device (1), each of said actuations having an operation time (T_operation1-T_operationN) associated thereto and said operation time comprising a configurable delay time (T_delay),characterized in that it comprises electronic means (1000) arranged to:
- count (600) a first operation time (T_operation1) associated to a first actuation of the switching device (100) caused by the coil actuator (1);
- determine (601) a correction time (T_correction) by comparing a target operation time (T_target) to said counted first operation time (T_operation1);
- apply (605) at least an amount of said correction time (T_correction) to the configurable delay time (T_delay) of an operation time (T_operation2-T_operationN) associated to at least one subsequent actuation of the switching device (100) caused by the coil actuator (1) and occurring after said first actuation, so as to modify said configurable delay time (T_delay) and reduce the difference between said operation time (T_operation2-T_operationN) and said target operation time (T_target);
- count (603) the corrected operation time (T_operation2-T_operationN) associated to said at least one subsequent actuation.
The coil actuator (1) according to claim 1, wherein said at least one subsequent actuation comprises at least a second actuation of the switching device occurring after said first actuation, and wherein said electronic means (1000) are arranged to apply (605) said correction time (T_correction) to the configurable delay time (T_delay) of the operation time (T_operation2) associated to said second actuation.
The coil actuator (1) according to claim 1, wherein said at least one subsequent actuation comprises a plurality of subsequent actuations of the switching device (100), and wherein said electronic means (1000) are arranged to:
- divide (604) said determined correction time (T_correction) into a plurality of addends (T_add1-T_addN-1); and
- apply (605₁-605_N-1) each addend of said plurality of addends (T_add1-Tadd_N-1) to the configurable delay time (T_delay) of a corresponding operation time (T_operation2-T_operationN) which is associated to an actuation of said plurality of subsequent actuations.
The coil actuator (1) according to one or more of the preceding claims, comprising a coil electromagnet (2) arranged to move between a rest position and an actuating position, wherein the movement from the rest position to the actuating position is suitable to cause the actuation of said switching device (100), and wherein said electronic means (1000) comprise:
- detection means (11) arranged to detect a first event;
- driving means (10) operatively associated to said detection means (11) and operatively connected to said coil electromagnet (2), said driving means (10) being arranged to electrically drive the coil electromagnet (2) to cause the movement of such coil electromagnet (2) from the rest position to the actuating position upon the detection of said first event by the detection means (11), said detection means (11) being arranged also to detect a second event which is indicative of the end of the actuation of the switching device (100) caused by said movement of the coil electromagnet (2) from the rest position to the actuating position;
- counting means (20) operatively associated to said detection means (11) and arranged to start counting when said first event is detected by the detection means (11) and to stop such counting when the second event is detected by the detection means (11).
The coil actuator (1) according to claim 4, wherein said driving means (10) are arranged to apply said configurable delay time (T_delay) between the detection of said first event and the consequent electrical driving of the coil electromagnet (2).
The coil actuator (1) according to claim 4 or claim 5, wherein said driving means (10) comprise a power input circuit (12) arranged to be operatively connected to and receive an input voltage (V_in) from at least a power source (200), said detection means (11) being arranged to sense a voltage indicative of said input voltage (V_in) and to detect a first threshold value (V_{th_launch}) and a second threshold value (V_{th_release}) of such input voltage (V_in), wherein the detection of said first threshold value (V_{th_launch}) and the detection of said second threshold value (V_{th_release}) correspond to said first event and said second event, respectively.
The coil actuator (1) according to claim 4 or 5, wherein said driving means (10) are operatively connected to at least a power source (500) so as to receive therefrom the power required to hold the coil electromagnet (2) in the rest position, and in that said detection means (11) are arranged to detect the falling of a voltage (V_supply) associated to said at least a power source (500) below a predetermined undervoltage threshold value, wherein the detection of such voltage falling corresponds to said first event.
A switching device (100)characterized in that it comprises at least a coil actuator (1) according to one or more of claims 1-7.
A switchgearcharacterized in that it comprises at least a switching device (100) according to claim 8 and/or at least a coil actuator (1) according to one or more of claims 1-7.
A method (700) for correcting operation times (T_operation1-T_operationN) counted by a coil actuator (1) and associated to actuations of a switching device (100) which are caused by said coil actuator (1), wherein each of said operation times comprises a configurable delay time (T_delay), the methodcharacterized in that it comprises:
- counting (600) a first operation time (T_operation1) associated to a first actuation of the switching device (100) caused by the coil actuator (1);
- determining (601) a correction time (T_correction) by comparing a target operation time (T_target) to said counted first operation time (T_operation1);
- applying (605) at least an amount of said correction time (T_correction) to the configurable delay time (T_delay) of an operation time (T_operation2-T_operationN) associated to at least one subsequent actuation of the switching device (100) caused by the coil actuator (1) and occurring after said first actuation, so as to modify said configurable delay time (T_delay) and reduce the difference between said operation time (T_operation2-T_operationN) and said target operation time (Ttarget);
- counting (603) the corrected operation time (T_operation2-T_operationN) associated to said at least one subsequent actuation.
The method (700) according to claim 10, wherein said at least one subsequent actuation of the switching device (100) comprises at least a second actuation occurring after said first actuation, and wherein applying (605) said at least an amount of the correction time (T_correction) comprises:
- applying (605) said correction time (T_correction) to the configurable delay time (T_delay) of the operation time (T_operation2) associated to said second actuation.
The method (700) according to claim 10, wherein said at least one subsequent actuation of the switching device (100) comprises a plurality of subsequent actuations, and wherein applying (605) at least an amount of said correction time (T_correction) comprises:
- dividing (604) said correction time (T_correction) into a plurality of addends (T_add1-T_addN-1);
- applying (605₁-605_N-1) each addend of said plurality of addends (T_add1-T_addN-1) to the configurable delay time (T_delay) of a corresponding operation time (T_operation2-T_operationN) which is associated to an actuation of said plurality of subsequent actuations.