Disclosure of Invention
The invention aims to provide a charging and discharging device and a control method, so as to solve the problem of high production cost of an electric automobile caused by the fact that a user charges the electric automobile conveniently in the prior art.
In order to achieve the above object, the present invention provides a charge and discharge device comprising:
a charge-discharge controller;
the bidirectional power supply module is electrically connected with the charge-discharge controller;
the charge-discharge gun is electrically connected with the charge-discharge controller;
the conversion connector is respectively connected with one end of the bidirectional power supply module and the charge-discharge controller;
the first control switch module is connected with the charge-discharge controller at a control end, the first connecting end is connected with the other end of the bidirectional power supply module, and the second connecting end is connected with the charge-discharge gun;
the insulation detection module is respectively connected with a circuit between the bidirectional power supply module and the charge-discharge gun and the charge-discharge controller;
the charging and discharging controller controls the insulation detection module to perform insulation detection in the process of communicating with the electric automobile through the charging and discharging gun, and stops charging and discharging when the insulation detection result does not meet the preset requirement; and when the insulation detection result meets the preset requirement, controlling the first control switch module to be closed.
Optionally, the charge-discharge controller is further configured to determine a working mode according to a type of an external device connected to the conversion connector, and control the bidirectional power supply module to switch to a corresponding working mode according to the working mode.
Optionally, the charge-discharge controller is further configured to control the first control switch module to be closed after receiving a ready message sent by the electric automobile, so that the charge-discharge gun is electrically connected with the bidirectional power supply module to perform charging or discharging.
Optionally, the insulation detection module includes:
a direct current charger for collecting a first voltage of a negative electrode of the bidirectional power supply module to the ground and a second voltage of the positive electrode of the bidirectional power supply module to the ground;
one end of the first switch is connected with the positive electrode of the direct current charger;
a fourth resistor and a second switch connected in series between the other end of the first switch and the ground;
a fifth resistor and a third switch connected in series between the negative electrode of the direct current charger and the ground terminal;
wherein the output voltage of the direct current charger is the sum of the first voltage and the second voltage; the voltage at two ends of the fourth resistor is the first voltage, and the voltage at two ends of the fifth resistor is the second voltage.
Optionally, the charge-discharge gun includes: a first connection confirmation end and a second connection confirmation end which are respectively connected with the charge-discharge controller;
when the charging and discharging gun is connected with the charging and discharging socket, the first connection confirmation end and the second connection confirmation end are respectively connected with a connection confirmation circuit of the electric automobile;
and the charge-discharge controller determines that the charge-discharge gun (3) is connected with the charge-discharge socket when detecting that the voltage of the first connection confirmation end is a first preset voltage and the voltage of the second connection confirmation end is a second preset voltage.
Optionally, a first resistor is connected in series between the first connection confirmation end and the power supply end; a second resistor and a normally closed switch are connected in series between the first connection confirmation end and the falling low end; and a third resistor is connected in series between the second connection confirmation end and the grounding end.
Optionally, the charging and discharging device further includes:
a storage battery;
the control end of the second control switch module is connected with the charge-discharge controller, the third connecting end is connected with the storage battery, and the fourth connecting end is connected with the charge-discharge gun;
after the charge-discharge controller determines that the charge-discharge gun is connected with the charge-discharge socket, the charge-discharge controller controls the second control switch module to be closed, so that the storage battery is electrically connected with the positive direct-current low-voltage end and the negative direct-current low-voltage end of the charge-discharge gun.
Optionally, the charge-discharge gun further includes: the first data communication end and the second data communication end are respectively connected with the charge-discharge controller;
after the charging and discharging gun is connected with the charging and discharging socket, the first data communication end and the second data communication end are respectively connected with the data communication end of the electric automobile;
after the second control switch module is controlled to be closed, the charge-discharge controller and the electric automobile are in data communication.
Optionally, the charge-discharge gun includes: a positive high voltage DC terminal and a negative high voltage DC terminal;
the positive high-voltage direct-current end and the negative high-voltage direct-current end are connected with the bidirectional power supply module through the first control switch module;
when the charging and discharging gun is connected with the charging and discharging socket, the positive high-voltage direct-current end and the negative high-voltage direct-current end are respectively connected with a power battery of the electric automobile.
The embodiment of the invention also provides a charge and discharge control method, which is characterized by comprising the following steps:
determining a working mode according to the type of the external device connected with the conversion connector;
controlling the bidirectional power supply module to switch to the working mode;
after the bidirectional power supply module is switched to the working mode, the bidirectional power supply module is communicated with an electric automobile; in the process of communicating with the electric automobile, insulation detection is carried out after a handshake message sent by the electric automobile is received;
if the insulation detection result meets the preset condition, after receiving a message that the electric automobile is ready, controlling the first control switch module to be closed so as to charge and discharge between the electric automobile and external equipment; and stopping charging and discharging if the insulation detection result does not meet the preset condition.
The technical scheme of the invention has at least the following beneficial effects:
in the charge-discharge device provided by the embodiment of the invention, the charge-discharge controller is used for controlling the insulation detection module to perform insulation detection on the charge-discharge device in the communication process of the electric automobile, when the insulation detection result meets the preset condition, the first control switch module is controlled to be closed, and when the insulation detection result does not meet the preset condition, the charge-discharge is stopped, so that the charge-discharge abnormality caused by the fact that the charge-discharge device is not insulated in the charge-discharge process is avoided; in addition, the charging and discharging device is independently arranged to charge or discharge the electric automobile, so that the grade of components used by the charging and discharging device is reduced, the high-voltage wire harness for connecting the vehicle-mounted charger with other parts is reduced, the requirement of charging by a user at any time and any place is met, and the production cost of the electric automobile is reduced.
Detailed Description
In order to make the technical problems, technical solutions and advantages to be solved more apparent, the following detailed description will be given with reference to the accompanying drawings and specific embodiments.
Aiming at the problem of high production cost of the electric automobile caused by the fact that the electric automobile is charged by a user in the prior art, the invention provides the charging and discharging device and the control method, which realize the independent setting of the charging and discharging device and reduce the production cost of the electric automobile on the basis of meeting the charging and discharging requirements of the electric automobile of the user.
Referring to fig. 1, a charge and discharge device according to an embodiment of the invention includes:
a charge-discharge controller 1;
the bidirectional power supply module 2 is electrically connected with the charge-discharge controller 1;
a charge-discharge gun 3 electrically connected to the charge-discharge controller 1;
a conversion connector 4 connected to one end of the bidirectional power supply module 2 and the charge/discharge controller 1, respectively;
the first control switch module S1 is connected with the charge-discharge controller 1 at a control end, the first connecting end is connected with the other end of the bidirectional power supply module 2, and the second connecting end is connected with the charge-discharge gun 3;
the insulation detection module 6 is respectively connected with the circuit between the bidirectional power supply module 2 and the charge-discharge gun 3 and the charge-discharge controller 1;
the charge-discharge controller 1 controls the insulation detection module 6 to perform insulation detection in the process of communicating with the electric automobile through the charge-discharge gun 3, and stops charging and discharging when the insulation detection result does not meet the preset requirement; and when the insulation detection result meets the preset requirement, controlling the first control switch module S1 to be closed.
In the embodiment of the present invention, the charge-discharge controller 1 is preferably an STM32 controller, and the bidirectional power supply module 2 is preferably an LLC bidirectional power supply; on one hand, components adopted by the charging and discharging device are reduced to industrial grade by separating the charging and discharging device from the electric automobile, so that the production cost is reduced; on the other hand, different from the direct current charging pile, the user can complete charging in any place with requirements such as residential areas by adopting the charging and discharging device; in addition, by arranging the insulation detection module 6, the insulation of the charging and discharging device is detected before the electric automobile and external equipment are charged and discharged, and the phenomenon of abnormal charging and discharging caused by uninstallation in the charging and discharging process is avoided.
Optionally, the charge-discharge controller 1 is further configured to determine an operation mode according to a type of an external device connected to the conversion connector 4, and control the bidirectional power supply module 2 to switch to a corresponding operation mode according to the operation mode. Wherein, the working modes comprise a charging mode and a discharging mode.
In the embodiment of the invention, the charge-discharge controller 1 automatically identifies the type of the external device connected with the conversion connector 4, and determines the current working mode, so as to control the bidirectional power module 2 to switch to the corresponding working mode, and realize the charge or discharge between the electric automobile and the external device at any place where the need exists.
Preferably, the conversion connector 4 includes a conversion socket and a conversion plug corresponding to the conversion socket;
wherein, the conversion socket is connected with the charge-discharge controller 1;
the conversion plug is connected with a power supply port of external equipment;
the switching plug is internally provided with an identification resistor, and when the switching plug is connected with the switching socket, the identification resistor is connected with the charge-discharge controller 1 through a working mode confirmation end in the switching socket;
the charge-discharge controller 1 determines the type of the external device according to the resistance value of the identification resistor, and determines the working mode according to the type of the external device.
Specifically, an identity recognition module is arranged in the charge-discharge controller 1, and the identity recognition module is connected with a working mode confirmation end in the conversion connector 4 and is used for determining the type of external equipment connected with the conversion connector 4 according to the resistance value of an identity recognition resistor in the conversion connector 4; the identity recognition module is used for determining the type of the external equipment according to the currently received resistance value of the identity recognition resistor and the corresponding relation table.
Preferably, when the type of the external device is a charging pile, determining that the working mode is a charging mode; and when the type of the external equipment is a socket, determining that the working mode is a discharging mode.
Further, the charge-discharge controller 1 is further configured to control the first control switch module S1 to be closed after receiving a ready message sent by the electric vehicle, so that the charge-discharge gun 3 is electrically connected with the bidirectional power module 2 to perform charging or discharging.
Optionally, as shown in fig. 2, the insulation detection module includes:
a direct current charger 11 for collecting a first voltage of the negative pole of the bidirectional power supply module 2 to the ground and a second voltage of the positive pole to the ground;
one end of the first switch K1 is connected with the positive electrode of the direct current charger 11;
a fourth resistor R4 and a second switch K2 connected in series between the other end of the first switch K1 and the ground;
a fifth resistor R5 and a third switch K3 connected in series between the negative electrode of the DC charger 11 and the ground terminal;
wherein the output voltage of the dc charger 11 is the sum of the first voltage and the second voltage; the voltage at two ends of the fourth resistor R4 is the first voltage, and the voltage at two ends of the fifth resistor R5 is the second voltage.
Specifically, in fig. 2, R-is the resistance of the negative electrode to the ground, r+ is the resistance of the positive electrode to the ground, R0 is an auxiliary resistance with a known resistance value, and the resistance value of R0 is preferably 500kΩ;
as shown in fig. 3, the insulation detection is performed as follows:
first, the detection module 6 collects the first voltage U11 And the second voltage U21 The method comprises the steps of carrying out a first treatment on the surface of the The output voltage of the dc charger 11 is Ub, whereby ub=u11 +U21 ，U11 /R-＝U21 /R+；
Second, for the first voltage U11 And a second voltage U21 Comparing, on the one hand, at the first voltage U11 Greater than the firstTwo voltages U21 When the insulation resistance of the positive electrode is determined to be smaller, the first switch K1 is closed, and the third voltage U of the negative electrode to the ground is re-measured12 And according to the first voltage U11 Second voltage U21 And a third voltage U12 The insulation resistance of the positive electrode to ground was calculated, where r+=r0 (1+U21 /U11 )(U11 /U12 -1)，R-＝U11 /U21 X r+; on the other hand, at the first voltage U11 Less than the second voltage U21 When the second switch K2 is closed, the fourth voltage U of the positive electrode to the ground is re-measured22 And according to the first voltage U11 Second voltage U21 And a fourth voltage U22 The insulation resistance of the positive electrode to ground is calculated, wherein R- =r0 (1+U11 /U21 )(U21 /U22 -1)，R+＝U21 /U11 X R-; on the other hand, if the above two conditions are not satisfied, if there may be a decrease in insulation resistance between the positive electrode and the negative electrode, the first switch K1 is closed, and the fifth voltage U13 of the negative electrode to the ground is re-measured, where r+=r0 (1+U21 /U11 )(U11 /U13 -1)，R+≈R-。
And judging whether at least one of the resistance value of the positive electrode to the ground and the resistance value of the negative electrode to the ground is smaller than a preset resistance value, if so, reporting insulation fault information to the charge and discharge controller 1, and if not, reporting insulation fault-free information to the charge and discharge controller 1.
When the charge/discharge controller 1 receives that the information reported by the insulation detection module 6 is insulation fault information, it stops communicating with the electric vehicle and reports insulation leakage fault; and when the received information is insulation fault-free information, continuing to communicate with the electric automobile.
Further, the charge and discharge device further includes:
a storage battery 5;
the control end of the second control switch module S2 is connected with the charge-discharge controller 1, the third connecting end is connected with the storage battery 5, and the fourth connecting end is connected with the charge-discharge gun 3;
after the charge-discharge controller 1 determines that the charge-discharge gun 3 is connected with the charge-discharge socket, the charge-discharge controller 1 controls the second control switch module S2 to be closed, so that the storage battery 5 is electrically connected with the positive dc low voltage end and the negative dc low voltage end of the charge-discharge gun 3.
In the embodiment of the present invention, the storage battery 5 is configured to provide a low voltage for the electric vehicle, so that the electric vehicle can perform data communication with the charging and discharging device. Of course, the electric vehicle may also utilize its own storage battery to supply power to the relevant components of the battery system, instead of the storage battery 5 in the embodiment of the present invention.
Optionally, the charge-discharge gun 3 further includes: a first data communication terminal and a second data communication terminal respectively connected with the charge-discharge controller 1;
after the charge-discharge gun 3 is connected with the charge-discharge socket, the first data communication end and the second data communication end are respectively connected with the data communication end of the electric automobile;
after the second control switch module S2 is controlled to be closed, the charge-discharge controller 1 performs data communication with the electric vehicle.
In the embodiment of the invention, the charge-discharge controller 1 performs data communication with the electric automobile, so that information interaction between the charge-discharge controller 1 and the electric automobile is realized, and the electric automobile and the external equipment are controlled to be charged or discharged through the charge-discharge device after the charge-discharge controller and the electric automobile are in a charge-discharge ready state.
Specifically, as shown in fig. 4, the specific process of data communication between the charge-discharge controller 1 and the electric vehicle is as follows:
information interaction in handshake phase:
firstly, when the charge-discharge controller 1 detects that the voltage of the first connection confirmation end is a first preset voltage value, the second control switch module S2 is closed, so that the storage battery 5 supplies power for the electric automobile at low voltage; of course, if the electric vehicle does not need the battery 5 to supply power; when the charge-discharge controller 1 detects that the voltage of the first connection confirmation end is a first preset voltage value, a Charger Handshake (CHM) message containing a communication protocol version number is sent to the electric automobile; secondly, after the electric automobile detects that the voltage of the second connection confirmation end is a second preset voltage value and receives a CHM message, the electric automobile confirms that the communication protocol sent by the charge-discharge control device is matched with the communication protocol of the electric automobile, and then sends a vehicle handshake (BHM) message to the charge-discharge controller 1; thirdly, after receiving the BHM message, the charge-discharge controller 1 sends a control instruction of insulation detection to the insulation detection module 6, receives an insulation detection result reported by the insulation detection module 6, stops communicating with the electric automobile if an insulation fault exists, and sends a charger identification (CRM) message including a charging pile number, a charging address and an identification result to the electric automobile if no insulation fault exists, wherein if no identification is completed, the sent identification result is 00, and if identification is passed, the sent identification result is AA; in the step, the identification result sent is not identified; fourth, after receiving the CRM message, the electric vehicle sends a BMS and a vehicle identification (BRM) message including battery electronic information, battery capacity and battery voltage to the charge-discharge controller 1; fifth, after receiving the BRM message, the charge-discharge controller 1 sends the CRM message again, and the identification is passed, and the handshake phase is completed.
The information interaction process in the configuration stage is as follows:
firstly, the electric automobile sends a power Battery Charging Parameter (BCP) message containing battery charging information, maximum allowed charging power, maximum allowed charging current and maximum allowed temperature to the charging and discharging controller 1; secondly, after receiving the BCP message, the charging and discharging device sends a charging machine sending time synchronization information (CTS) message containing the specific time of charging to the electric automobile; thirdly, after sending the BCP message for a preset time, the charge-discharge controller 1 sends a maximum output Capacity (CML) message of the charger containing the highest voltage and current receivable by the dc-dc module to the electric vehicle; fourth, after the electric automobile receives the CML message, it sends a battery charge ready state (BRO) message containing that the vehicle is not ready to charge to the charging and discharging device; fifthly, the electric automobile controls a main positive relay and a main negative relay which are connected with a power battery to be closed; sixthly, the electric automobile sends a BRO message containing that the vehicle is ready to charge to the charging and discharging device. Seventh, after receiving the BRO message, the charge-discharge controller 1 sends a CRO message that includes that the external device is not ready to the electric automobile; eighth, after sending a CRO message to the electric automobile, after detecting that the bidirectional power module 2 is in a ready state, the first control switch module S1 is closed, and a CRO message including that an external device is ready is sent to the electric automobile, so far, the charging and discharging device confirms that the external device and the electric automobile are currently in a ready state, and charging and discharging can be started.
Optionally, the charge-discharge gun 3 includes: a first connection confirmation terminal and a second connection confirmation terminal respectively connected with the charge-discharge controller 1;
when the charge-discharge gun 3 is connected with the charge-discharge socket, the first connection confirmation end and the second connection confirmation end are respectively connected with a connection confirmation circuit of the electric automobile;
when the charge-discharge controller 1 detects that the voltage of the first connection confirmation terminal is a first preset voltage and the voltage of the second connection confirmation terminal is a second preset voltage, it determines that the charge-discharge gun 3 is connected with the charge-discharge socket.
Specifically, after the charge-discharge device is connected with the electric vehicle, the charge-discharge device and the connection confirmation circuit of the electric vehicle form a loop, the first connection confirmation end has a voltage value and the second connection confirmation end has another voltage value through the voltage division of each device in the loop, and when the charge-discharge controller 1 detects that the voltage value on the first connection confirmation end is a first preset voltage value and the electric vehicle detects that the voltage value on the second connection confirmation end is a second preset voltage value, it is determined that the charge-discharge gun 3 is well connected with the charge-discharge socket of the electric vehicle. Preferably, the first preset voltage value is 4V, and the second preset voltage value is 6V.
Optionally, a first resistor R1 is connected in series between the first connection confirmation end and the power supply end; a second resistor R2 and a normally closed switch S3 are connected in series between the first connection confirmation end and the falling low end; and a third resistor R3 is connected in series between the second connection confirmation end and the grounding end. After the charging and discharging gun 3 is well connected with the charging socket, the first resistor R1, the second resistor R2 and a connection confirmation circuit in the electric automobile form a closed loop, and the voltage of the first connection confirmation end is a first preset voltage value and the voltage of the second connection confirmation end is a second preset voltage value through voltage division of the resistors.
It should be noted that the power supply terminal is a pull-up power supply for providing a voltage for the first resistor R1 and the second resistor R2.
Optionally, the charge-discharge gun 3 includes: a positive high voltage DC terminal and a negative high voltage DC terminal;
the positive high-voltage direct-current end and the negative high-voltage direct-current end are connected with the bidirectional power supply module 2 through the first control switch module S1;
when the charging and discharging gun 3 is connected with the charging and discharging jack, the positive high-voltage direct-current end and the negative high-voltage direct-current end are respectively connected with a power battery of the electric automobile.
The bidirectional power module 2 is further connected with an external device through the positive charge and discharge end and the negative charge and discharge end of the conversion connector 4, so that when the first switch control module S1 is closed, a power battery of the electric automobile and the external device form a passage.
The charging and discharging device realizes separation from the electric automobile, reduces the level of components selected by the charging and discharging device, avoids connection with other parts on the electric automobile through a high-voltage wire harness, and reduces the production cost of the electric automobile; in addition, the independent setting of a charge-discharge device ensures that a user charges or discharges at any needed time and place, realizes the integrated charge-discharge setting, reduces the production cost on the basis of meeting the user demand, in addition, by setting the insulation detection module 6, realizes the insulation detection of the charge-discharge device before charging or discharging, stops the insulation detection when the insulation is abnormal, and improves the safety of the user using the charge-discharge device.
The embodiment of the invention also provides a charge and discharge control method, which comprises the following steps:
determining a working mode according to the type of the external device connected with the conversion connector;
controlling the bidirectional power supply module to switch to the working mode;
after the bidirectional power supply module is switched to the working mode, the bidirectional power supply module is communicated with an electric automobile; in the process of communicating with the electric automobile, insulation detection is carried out after a handshake message sent by the electric automobile is received;
if the insulation detection result meets the preset condition, after receiving a message that the electric automobile is ready, controlling the first control switch module to be closed so as to charge and discharge between the electric automobile and external equipment; and stopping charging and discharging if the insulation detection result does not meet the preset condition.
The present embodiment is preferably applied to the charge and discharge device as described above, wherein the process of communicating with the electric vehicle may refer to the process of data communication between the charge and discharge controller 1 and the electric vehicle in the charge and discharge device embodiment.
While the foregoing is directed to the preferred embodiments of the present invention, it will be appreciated by those skilled in the art that various modifications and adaptations can be made without departing from the principles of the present invention, and such modifications and adaptations are intended to be comprehended within the scope of the present invention.