Disclosure of Invention
The invention aims to provide a vehicle fault diagnosis circuit, a vehicle fault diagnosis method and a vehicle, which can solve the technical problem that fault diagnosis can only be carried out in a short time in a system power-on self-test process in the prior art.
According to a first aspect of the present invention, there is provided a fault diagnosis circuit for a vehicle, including an auxiliary diagnosis power supply circuit, a high-side sampling circuit, a low-side sampling circuit, a coil loop current detection circuit, a coil, a high-side switch, and a low-side switch;
the auxiliary diagnosis power supply circuit is connected with the coil loop current detection circuit and is used for controlling the on-off of an auxiliary diagnosis power supply;
The coil loop current detection circuit is connected with the first end of the coil, the first end of the coil is connected with the high-side switch, and the coil loop current detection circuit is used for detecting the current of the coil loop;
the high-side sampling circuit is connected with the first end of the coil and is used for collecting high-side voltage of the coil;
the low-side sampling circuit is connected with the second end of the coil, the second end of the coil is connected with the low-side switch, and the low-side sampling circuit is used for collecting low-side voltage of the coil.
Optionally, the auxiliary diagnostic power supply circuit includes a composite transistor including a first transistor and a second transistor;
the auxiliary diagnosis power supply is respectively connected with the emitter of the second transistor and the first end of the first resistor, the base of the second transistor is respectively connected with the second end of the first resistor and the first end of the second resistor, the second end of the second resistor is connected with a control signal, and the control signal is used for controlling the on-off of the composite transistor;
and the collector of the second transistor is respectively connected with the base electrode of the first transistor and the emitter of the first transistor, and the collector of the first transistor is connected with the coil loop current detection circuit.
Optionally, the first transistor is an NPN transistor, and the second transistor is a PNP transistor.
Optionally, the coil loop current detection circuit includes a third resistor, a fourth resistor, a fifth resistor, a first capacitor, and a second capacitor;
the first end of the third resistor is connected with the first end of the fourth resistor and the collector electrode of the first transistor respectively, and the second end of the third resistor is connected with the first end of the fifth resistor and the first end of the coil respectively;
the second end of the fourth resistor is connected with the first end of the first capacitor and the first sampling port respectively, the second end of the fifth resistor is connected with the second end of the second capacitor and the second sampling port respectively, and the second end of the first capacitor and the second end of the second capacitor are grounded.
Optionally, the high-side sampling circuit includes a sixth resistor, a seventh resistor and a third capacitor;
the first end of the sixth resistor is connected with the first end of the coil, the second end of the sixth resistor is respectively connected with the first end of the seventh resistor, the first end of the third capacitor and the third sampling port, and the second end of the seventh resistor and the second end of the third capacitor are grounded.
Optionally, the low-side sampling circuit includes an eighth resistor, a ninth resistor and a fourth capacitor;
the first end of the eighth resistor is connected with the second end of the coil, the second end of the eighth resistor is respectively connected with the first end of the ninth resistor, the first end of the fourth capacitor and the fourth sampling port, and the second end of the ninth resistor and the second end of the fourth capacitor are grounded.
Optionally, the high side switch includes a first NMOS transistor and the low side switch includes a second NMOS transistor.
According to a second aspect of the present invention, there is provided a diagnostic method for a fault diagnosis circuit for a vehicle to which the first aspect of the present invention is applied, comprising:
after the system is electrified, acquiring the starting state of an auxiliary diagnosis power supply, the starting state of a high-side switch and the starting state of a low-side switch;
if the auxiliary diagnosis power supply is in a closed state, the high-side switch is in a closed state, and the low-side switch is in a closed state, determining that the fault type is high-side MOS breakdown or high-side short power supply under the condition that the coil high-side voltage is more than 2V;
if the auxiliary diagnosis power supply is in a closed state, the high-side switch is in an open state, and the low-side switch is in a closed state, determining that the fault type is a coil open circuit or a low-side MOS open fault under the condition that the coil high-side voltage is more than 9V and the coil low-side voltage is less than 2V;
If the auxiliary diagnosis power supply is in a closed state, the high-side switch is in an open state, the low-side switch is in a closed state, and when the coil high-side voltage is smaller than 9V, the high-side switch is closed and the auxiliary diagnosis power supply is opened, the fault type is determined to be a high-side open circuit or a high-side driving fault under the condition that the coil high-side voltage is larger than 4V, and the fault type is determined to be a high-side short ground under the condition that the coil high-side voltage is smaller than 2V;
If the auxiliary diagnosis power supply is in a closed state, the high-side switch is in an open state, and the low-side switch is in an open state, determining that the fault type is a coil short circuit when the coil high-side voltage is smaller than 2V, and determining that the fault type is a low-side MOS open circuit fault when the coil high-side voltage is larger than 2V and the coil low-side voltage is larger than 2V;
And if the auxiliary diagnosis power supply is in an on state, the high-side switch is in an off state and the low-side switch is in an off state, determining that the fault type is coil overcurrent under the condition that the difference value between two voltage values output by the coil loop current detection circuit is larger than a threshold value.
According to a third aspect of the present invention, there is provided a diagnostic method for a fault diagnosis circuit for a vehicle to which the first aspect of the present invention is applied, comprising:
In the process of inspection, acquiring the starting state of an auxiliary diagnosis power supply, the starting state of a high-side switch and the starting state of a low-side switch;
If the auxiliary diagnosis power supply is in an on state, the high-side switch is in an off state, the low-side switch is in an off state, the fault type is determined to be high-side MOS breakdown or high-side short power supply when the coil high-side voltage is greater than 4V, the fault type is determined to be high-side short ground when the coil high-side voltage is less than 2V, and the fault type is determined to be coil open fault or low-side MOS open fault when the coil high-side voltage is greater than 2V and less than 4V and the coil low-side voltage is less than 2V;
If the auxiliary diagnosis power supply is in an on state, the high-side switch is in an off state, the low-side switch is in an on state, the fault type is determined to be a coil short circuit under the condition that the coil high-side voltage is smaller than 2V, the fault type is determined to be a low-side MOS open circuit fault under the condition that the coil high-side voltage is larger than 2V and the coil low-side voltage is larger than 2V, and the difference value between two voltage values output by the coil loop current detection circuit is larger than a threshold value, the fault type is determined to be a coil overcurrent.
According to a fourth aspect of the present invention, there is provided a vehicle including the failure diagnosis circuit for a vehicle according to the first aspect of the present invention.
The electromagnetic valve has the beneficial effects that the auxiliary diagnosis power supply circuit is arranged, so that the auxiliary diagnosis power supply circuit controls the on-off of an auxiliary diagnosis power supply, diagnosis can be realized, current passing through the coil can be controlled, the electromagnetic force of the coil is insufficient to change the existing state of the electromagnetic valve, and the coil can be detected without opening a high-side safety switch. Meanwhile, the diagnosis is controllable, and the increase of static working current is avoided. And when short circuit fault occurs, the auxiliary diagnosis power supply can be turned off, so that the safety is improved.
Detailed Description
Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated otherwise.
The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of exemplary embodiments may have different values.
It should be noted that like reference numerals and letters refer to like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.
In the description and claims of the present invention, the terms "first," "second," and the like, if any, may include one or more of those features, either explicitly or implicitly. In the description of the present invention, unless otherwise indicated, the meaning of "a plurality" is two or more. Furthermore, in the description and claims, "and/or" means at least one of the connected objects, and the character "/", generally means that the associated object is an "or" relationship.
As shown in fig. 1, the present embodiment describes a fault diagnosis circuit for a vehicle, including an auxiliary diagnosis power supply circuit, a high-side sampling circuit, a low-side sampling circuit, a coil loop current detection circuit, a coil, a high-side switch, and a low-side switch.
The auxiliary diagnosis power circuit is connected with the coil loop current detection circuit and is used for controlling on-off of an auxiliary diagnosis power supply.
The coil loop current detection circuit is connected with the first end of the coil, the first end of the coil is connected with the high-side switch, and the coil loop current detection circuit is used for detecting the current of the coil loop.
The high-side sampling circuit is connected with the first end of the coil and is used for collecting high-side voltage of the coil.
The low-side sampling circuit is connected with the second end of the coil, the second end of the coil is connected with the low-side switch, and the low-side sampling circuit is used for collecting low-side voltage of the coil.
As shown in fig. 2, the high side switch and the low side switch are composed of NMOS, and driving is controlled by ASIC chip. The high-side switch comprises a first NMOS transistor DRVM1, and the first NMOS transistor DRVM1 is controlled to be turned on or off by a driving signal RCOIL _GATE1, so that the high-side switch is turned on or off. The low-side switch comprises a second NMOS transistor DRVM2, and the second NMOS transistor DRVM2 is controlled to be turned on or off by a driving signal RCOIL _GATE2, so that the low-side switch is turned on or off.
The types of faults are classified into high side switch faults, coil faults, and low side switch faults. The high side faults include overcurrent, high side open circuit, high side short power supply, high side short ground and the like. Coil faults include faults such as coil short circuit, coil open circuit, coil overload, etc. Low side faults include low side open circuits, low side short power supplies, low side short grounds, etc. And determining a specific fault type according to the sampling result of the high-side sampling circuit, the sampling result of the low-side sampling circuit and the detection result of the coil loop current detection circuit.
The auxiliary diagnosis power circuit is arranged, so that the auxiliary diagnosis power circuit controls the on-off of the auxiliary diagnosis power, diagnosis can be realized, current passing through the coil can be controlled, electromagnetic force of the coil is insufficient to change the existing state of the electromagnetic valve, and the coil can be detected without opening a high-side safety switch. Meanwhile, the diagnosis is controllable, and the increase of static working current is avoided. And when short circuit fault occurs, the auxiliary diagnosis power supply can be turned off, so that the safety is improved.
As shown in fig. 2, the auxiliary diagnostic power supply circuit in this embodiment includes a composite transistor including a first transistor Q1A and a second transistor Q1B. The first transistor Q1A is an NPN transistor, and the second transistor Q1B is a PNP transistor.
The auxiliary diagnostic power supply VCC is respectively connected with the emitter of the second transistor Q1B and the first end of the first resistor R1, the base of the second transistor Q1B is respectively connected with the second end of the first resistor R1 and the first end of the second resistor R2, the second end of the second resistor R2 is connected with the control signal RCOIL _ctrl, and the control signal RCOIL _ctrl is used for controlling the on-off state of the composite transistor.
The collector of the second transistor Q1B is connected to the base of the first transistor Q1A and the emitter of the first transistor Q1A, respectively, and the collector of the first transistor Q1A is connected to the coil loop current detection circuit.
The control signal RCOIL _CTRL is switched between high and low levels, so that the on-off control of the composite transistor can be realized, and the auxiliary diagnosis power supply can be further turned on or off.
As shown in fig. 2, in the present embodiment, the coil loop current detection circuit includes a third resistor R3, a fourth resistor R4, a fifth resistor R5, a first capacitor C1, and a second capacitor C2.
The first end of the third resistor R3 is connected to the first end of the fourth resistor R4 and the collector of the first transistor Q1A, and the second end of the third resistor R3 is connected to the first end of the fifth resistor R5 and the first end of the coil.
The second end of the fourth resistor R4 is connected to the first end of the first capacitor C1 and the first sampling port RCOIL _test1, the second end of the fifth resistor R5 is connected to the second end of the second capacitor C2 and the second sampling port RCOIL _test2, and the second ends of the first capacitor C1 and the second capacitor C2 are grounded.
The third resistor R3 is a high-precision sampling resistor, and the voltage difference between the first sampling port RCOIL _test1 and the second sampling port RCOIL _test2 is proportional to the current flowing through the third resistor R3, thereby calculating the current of the coil loop.
In this embodiment, the high-side sampling circuit includes a sixth resistor R6, a seventh resistor R7, and a third capacitor C3. The first end of the sixth resistor R6 is connected to the first end of the coil, the second end of the sixth resistor R6 is connected to the first end of the seventh resistor R7, the first end of the third capacitor C3 and the third sampling port RCOIL _sup_fbk, respectively, and the second end of the seventh resistor R7 and the second end of the third capacitor C3 are grounded.
As shown in FIG. 2, the sixth resistor R6 collects the coil height Bian Dianya, and the sixth resistor R6 and the seventh resistor form a voltage dividing circuit to convert the high-side voltage of the coil into a voltage within a voltage range recognizable by the singlechip. The third capacitor C3 is used to filter out interference.
In this embodiment, the low-side sampling circuit includes an eighth resistor R8, a ninth resistor R9, and a fourth capacitor C4. The first end of the eighth resistor R8 is connected to the second end of the coil, the second end of the eighth resistor R8 is connected to the first end of the ninth resistor R9, the first end of the fourth capacitor C4 and the fourth sampling port fr_nc_fbk, respectively, and the second end of the ninth resistor R9 and the second end of the fourth capacitor C4 are grounded.
As shown in FIG. 2, the eighth resistor R8 collects the low-side voltage of the coil, and the eighth resistor R8 and the ninth resistor R9 form a voltage dividing circuit to convert the low-side voltage of the coil into a voltage within a voltage range recognizable by the singlechip. The fourth capacitor is used for filtering interference.
The invention can realize the fault diagnosis during idle time inspection and system power-on.
As shown in fig. 3, this embodiment describes a diagnosis method for a fault diagnosis circuit for a vehicle, which is applied to any embodiment of the present invention, and includes:
after the system is electrified, acquiring the starting state of an auxiliary diagnosis power supply, the starting state of a high-side switch and the starting state of a low-side switch;
if the auxiliary diagnosis power supply is in a closed state, the high-side switch is in a closed state, and the low-side switch is in a closed state, determining that the fault type is high-side MOS breakdown or high-side short power supply under the condition that the coil high-side voltage is more than 2V;
if the auxiliary diagnosis power supply is in a closed state, the high-side switch is in an open state, and the low-side switch is in a closed state, determining that the fault type is a coil open circuit or a low-side MOS open fault under the condition that the coil high-side voltage is more than 9V and the coil low-side voltage is less than 2V;
If the auxiliary diagnosis power supply is in a closed state, the high-side switch is in an open state, the low-side switch is in a closed state, and when the coil high-side voltage is smaller than 9V, the high-side switch is closed and the auxiliary diagnosis power supply is opened, the fault type is determined to be a high-side open circuit or a high-side driving fault under the condition that the coil high-side voltage is larger than 4V, and the fault type is determined to be a high-side short ground under the condition that the coil high-side voltage is smaller than 2V;
If the auxiliary diagnosis power supply is in a closed state, the high-side switch is in an open state, and the low-side switch is in an open state, determining that the fault type is a coil short circuit when the coil high-side voltage is smaller than 2V, and determining that the fault type is a low-side MOS open circuit fault when the coil high-side voltage is larger than 2V and the coil low-side voltage is larger than 2V;
And if the auxiliary diagnosis power supply is in an on state, the high-side switch is in an off state and the low-side switch is in an off state, determining that the fault type is coil overcurrent under the condition that the difference value between two voltage values output by the coil loop current detection circuit is larger than a threshold value.
RCOIL _CTRL OFF indicates that the auxiliary diagnostic power supply is in an OFF state, and RCOIL _CTRL ON indicates that the auxiliary diagnostic power supply is in an ON state. RCOIL _gate1 OFF indicates that the high side switch is OFF, RCOIL _gate1 ON indicates that the high side switch is ON. RCOIL _gat2 OFF indicates that the low side switch is OFF, RCOIL _gat2 ON indicates that the low side switch is ON.
RCOIL _sup_fbk is the coil high Bian Dianya collected by the high side sampling circuit, fr_nc_fbk is the coil low side voltage collected by the low side sampling circuit, and RCOIL _test1 and RCOIL _test2 are the two voltages collected by the coil loop current detection circuit.
As shown in fig. 4, this embodiment describes a diagnosis method for a fault diagnosis circuit for a vehicle according to any one of the embodiments of the present invention, which is a fault diagnosis for inspection at idle time, and includes:
In the process of inspection, acquiring the starting state of an auxiliary diagnosis power supply, the starting state of a high-side switch and the starting state of a low-side switch;
If the auxiliary diagnosis power supply is in an on state, the high-side switch is in an off state, the low-side switch is in an off state, the fault type is determined to be high-side MOS breakdown or high-side short power supply when the coil high-side voltage is greater than 4V, the fault type is determined to be high-side short ground when the coil high-side voltage is less than 2V, and the fault type is determined to be coil open fault or low-side MOS open fault when the coil high-side voltage is greater than 2V and less than 4V and the coil low-side voltage is less than 2V;
If the auxiliary diagnosis power supply is in an on state, the high-side switch is in an off state, the low-side switch is in an on state, the fault type is determined to be a coil short circuit under the condition that the coil high-side voltage is smaller than 2V, the fault type is determined to be a low-side MOS open circuit fault under the condition that the coil high-side voltage is larger than 2V and the coil low-side voltage is larger than 2V, and the difference value between two voltage values output by the coil loop current detection circuit is larger than a threshold value, the fault type is determined to be a coil overcurrent.
This embodiment describes a vehicle including a fault diagnosis circuit for a vehicle according to any one of the embodiments of the present invention.
While certain specific embodiments of the invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the invention. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.
Those of ordinary skill in the art will appreciate that the modules and algorithm steps described in connection with the embodiments disclosed herein can be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.
It will be clearly understood by those skilled in the art that, for convenience and brevity of description, specific working procedures of the apparatus and device described above may refer to corresponding procedures in the foregoing method embodiments, which are not described herein again.
In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, and for example, the division of the modules is merely a logical function division, and there may be additional divisions when actually implemented, for example, multiple modules or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or modules, which may be in electrical, mechanical, or other forms.
The modules described as separate components may or may not be physically separate, and components shown as modules may or may not be physical modules, i.e., may be located in one place, or may be distributed over a plurality of network modules. Some or all of the modules can be selected according to actual needs to achieve the purpose of the embodiment of the invention.
In addition, each functional module in the embodiment of the present invention may be integrated in one processing module, or each module may exist alone physically, or two or more modules may be integrated in one module.
The functions, if implemented in the form of software functional modules and sold or used as a stand-alone product, may be stored in a computer-readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art or in a part of the technical solution in the form of a software product stored in a storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a server, a network device, etc.) to perform all or part of the steps of the method of the various embodiments of the present invention. The storage medium includes various media capable of storing program codes such as a U disk, a mobile hard disk, a ROM, a RAM, a magnetic disk or an optical disk.
The above description is only illustrative of the preferred embodiments of the present application and of the principles of the technology employed. It will be appreciated by persons skilled in the art that the scope of the application referred to in the present application is not limited to the specific combinations of the technical features described above, but also covers other technical features formed by any combination of the technical features described above or their equivalents without departing from the inventive concept. Such as the above-mentioned features and the technical features disclosed in the present application (but not limited to) having similar functions are replaced with each other.
It should be understood that, the sequence numbers of the steps in the summary and the embodiments of the present invention do not necessarily mean the order of execution, and the execution order of the processes should be determined by the functions and the internal logic, and should not be construed as limiting the implementation process of the embodiments of the present invention. The foregoing description of implementations of the present disclosure has been presented for purposes of illustration and description. The foregoing description is not intended to be exhaustive or to limit the disclosure to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the disclosure. The embodiments were chosen and described in order to explain the principles of the present disclosure and its practical application to enable one skilled in the art to utilize the present disclosure in various embodiments and with various modifications as are suited to the particular use contemplated.