Contactor control system and method

Abstract

The invention discloses a contactor control system and method, and belongs to the technical field of contactor control, the contactor control system comprises an intelligent control unit and a power grid circuit breaking unit, the intelligent control unit is connected with the power grid circuit breaking unit, and the intelligent control unit is connected with a contactor. According to the control system and method of the contactor, bidirectional abnormal large current can be identified through the intelligent control unit, and the contactor is controlled to cut off a high-voltage loop; the contactor can be closed again after system self-inspection is normal, so that multiple intelligent breaking is realized; and the health state of the contactor can be monitored in real time.

Description

Technical Field

[0001] This invention relates to the field of contactor control technology, and in particular to a contactor control system and method. Background Technology

[0002] The increasing power levels and charging rates of vehicle electrical systems have led to a growing demand for continuous high-current applications. Traditional electrical system protection measures include fuses and contactors. A fuse is a one-time device, which can be a thermal fuse or a pyrotechnic fuse; both irreversibly disconnect the electrical connection to prevent short circuits or fires. A high-voltage DC contactor is an electrical device used to control high-voltage DC circuits. Its main function is to achieve switching control in high-voltage DC circuits to ensure the normal operation of the circuit. In high-voltage DC transmission systems, it effectively controls the switching of circuits, ensuring the stable operation of the power system.

[0003] With the rapid development of the new energy and energy storage industries, the power of power systems is increasing, and the current is also increasing. Traditional contactors are generally only used as switches to control DC current, with control current typically between 20 and 600A. When a large current suddenly occurs in the system, the contactor cannot disconnect in time, and an electric arc of several thousand degrees Celsius will be generated between the contacts. This arc can cause the contacts to stick together, leading to the contactor malfunctioning. In severe cases, it can even cause the contactor to explode, posing a great threat to the power system. In addition, after prolonged use, the contact unit structure will oxidize and wear, leading to increased contact resistance. This not only causes the temperature between the contacts to rise and lead to sticking, greatly affecting the service life of the contactor, but also increases the power consumption of the high-voltage circuit.

[0004] Therefore, there is an urgent need for a contactor control system and method that can monitor the health status of the contactor in real time and perform multiple high-voltage disconnections by intelligently identifying abnormal high currents. Summary of the Invention

[0005] The present invention aims to provide a control system and method for a contactor.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] A control system for a contactor includes an intelligent control unit and a power grid disconnection unit, wherein the intelligent control unit is connected to the power grid disconnection unit and the contactor is also connected to the intelligent control unit.

[0008] Furthermore, the intelligent control unit includes a disconnection module, a control module, and a loop current monitoring module. The disconnection module is connected to the control module and the contactor's operating unit. The control module is connected to the loop current monitoring module, and the loop current monitoring module is connected to the contactor's contact unit.

[0009] Furthermore, the power grid disconnection unit includes a power management module and a signal processing module. The signal processing module is connected to the control module and the power management module, and the power management module is connected to one or more modules in the intelligent control unit.

[0010] Furthermore, the intelligent control unit includes a thermistor connected to a contact unit.

[0011] Furthermore, the power grid disconnection unit includes a communication module, and the signal processing module is connected to the power management module and the control module through the communication module.

[0012] Furthermore, the control module is a logic control module or a microcontroller unit.

[0013] In one specific embodiment, the loop current monitoring module includes a magnetic induction module, which employs a switched magnetic device. The first end of the magnetic induction module collects the high-voltage loop current, and the second end of the magnetic induction module is connected to the disconnection module.

[0014] In one specific embodiment, the loop current monitoring module includes a high-voltage isolation comparison module and a current sampling module. The current sampling module is connected in series between the contact unit and the high-voltage loop. The first end of the high-voltage isolation comparison module is connected to the current sampling module, and the second end of the high-voltage isolation comparison module is connected to the disconnection module.

[0015] The present invention also provides a control method for a contactor, applied to the control system of the aforementioned contactor, comprising: determining a bidirectional abnormal current:

[0016] Step S11: Monitor the high-voltage circuit current in real time;

[0017] Step S12: Determine whether the high-voltage circuit current is greater than the forward current threshold or the reverse current threshold. If either of the two conditions is met, proceed to step S13; otherwise, return to step S11 and continue monitoring.

[0018] Step S13: The disconnect module outputs a level signal to the action unit;

[0019] Step S14: Cut off the power supply to the contactor coil, and disconnect the high-voltage circuit.

[0020] The present invention provides a contactor control method, which further includes:

[0021] Step S15: Determine if the system self-test is normal. If not, proceed to step S18; if yes, proceed to step S16.

[0022] Step S16: The power management module restarts power supply or sends a reset signal to the control module;

[0023] Step S17: The control module outputs a reset signal to the disconnect module, and the disconnect module outputs a reset level signal to the action unit to supply power to the contactor coil and connect the high voltage circuit.

[0024] Step S18: No action is taken; the contactor remains disconnected.

[0025] The present invention provides a control method for a contactor, which further includes a coordinated determination of multiple abnormal currents:

[0026] Step S21: The magnetic induction module monitors the high-voltage circuit current in real time, and the high-voltage isolation comparison module monitors the high-voltage circuit current in real time.

[0027] Step S22: Determine whether the high-voltage circuit current monitored by the magnetic induction module is greater than the forward current threshold or the reverse current threshold, and determine whether the high-voltage circuit current monitored by the high-voltage isolation comparison module is greater than the forward current threshold or the reverse current threshold. If one of the two conditions is met or both conditions are met simultaneously, proceed to step S23; otherwise, return to step S21 and continue monitoring.

[0028] Step S23: The disconnect module outputs a level signal to the action unit;

[0029] Step S24: Cut off the power supply to the contactor coil, and disconnect the high-voltage circuit.

[0030] The present invention provides a control method for a contactor, which further includes health status monitoring:

[0031] Step S31: Real-time acquisition of the temperature of the contact unit and the contact resistance value of the contact unit.

[0032] Step S32: Determine whether the collected contact resistance value is greater than the contact resistance threshold and whether the collected temperature of the contact unit is greater than the temperature threshold. If one or both conditions are met, proceed to step S33; otherwise, return to step S31 and continue monitoring.

[0033] Step S33: Send an alert message.

[0034] The present invention also provides a contactor, including a control system for the contactor described above, wherein the contactor includes an actuating unit and a contact unit, and the actuating unit is connected to the contact unit.

[0035] Beneficial effects: The present invention provides a contactor control system and method that can identify bidirectional abnormal high currents through an intelligent control unit and control the contactor to cut off the high-voltage circuit; after the system self-test is normal, it can re-close the contactor, thereby realizing multiple intelligent disconnections; it can realize the coordinated judgment of multiple abnormal currents; the intelligent control unit monitors the contact resistance and temperature of the contactor contact unit, compares them with preset life parameters, monitors the health status of the contactor in real time, and issues warning information when necessary.

[0036] To make the above-mentioned features and advantages of the invention more apparent and understandable, specific embodiments are described below, and detailed descriptions are provided in conjunction with the accompanying drawings. Attached Figure Description

[0037] Figure 1 This is a structural block diagram of a contactor control system according to the present invention.

[0038] Figure 2 for Figure 1 A structural block diagram of a specific embodiment.

[0039] Figure 3 for Figure 1 A structural block diagram of another specific embodiment.

[0040] Figure 4 This is a circuit diagram of a specific embodiment of the disconnection module and the loop current monitoring module.

[0041] Figure 5 This is a circuit diagram of another specific embodiment of the disconnection module and the loop current monitoring module.

[0042] Figure 6 A flowchart for determining bidirectional abnormal current.

[0043] Figure 7 This is a flowchart for the collaborative determination of multiple abnormal currents.

[0044] Figure 8 A flowchart for health status monitoring.

[0045] Figure 9 This is a timing diagram for abnormal current control of a contactor control system and method according to the present invention. Detailed Implementation

[0046] To make the objectives and technical solutions of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0047] Figure 1 This is a structural block diagram of a contactor control system according to the present invention. Figure 1 As shown, the control system 1 of the contactor of the present invention is connected to the contactor 2 and is used to control the contactor 2.

[0048] Furthermore, the control system 1 of the contactor of the present invention includes an intelligent control unit 11 and a power grid disconnection unit 12. The intelligent control unit 11 is connected to the power grid disconnection unit 12, and the intelligent control unit 11 is connected to the contactor 2. The contactor 2 is connected in the high voltage circuit 3.

[0049] More specifically, the intelligent control unit 11 monitors the high-voltage circuit current in real time. If the high-voltage circuit current exceeds a current threshold, it controls the contactor 2 to disconnect. Simultaneously, it sends a feedback signal to the power grid disconnect unit 12, which confirms the abnormal current scenario based on the signal. Once the system self-test is normal, the power grid disconnect unit 12 restarts power supply or sends a reset signal to the intelligent control unit 11. The intelligent control unit 11 then controls the contactor 2 to close, reconnecting the high-voltage circuit 3.

[0050] Further, please refer to Figure 2 The contactor 2 includes an actuation unit 21 and a contact unit 22, and the actuation unit 21 and the contact unit 22 are connected.

[0051] Furthermore, the intelligent control unit 11 includes a disconnection module 111, a control module 112, and a loop current monitoring module 113. The disconnection module 111 is connected to the control module 112 and the action unit 21. The control module 112 is connected to the loop current monitoring module 113. The loop current monitoring module 113 is connected to the contact unit 22.

[0052] Optionally, the loop current monitoring module 113 can also be directly connected to the disconnection module 111.

[0053] Furthermore, the power grid disconnection unit 12 includes a power management module 121 and a signal processing module 122. The signal processing module 122 is connected to the control module 112 and the power management module 121. The power management module 121 is connected to one or more modules in the intelligent control unit 11 to supply power to them.

[0054] Optionally, the power management module 121 provides a 12V voltage.

[0055] More specifically, the loop current monitoring module 113 monitors the high-voltage loop current in real time and transmits it to the control module 112 or the disconnection module 111. After the control module 112 determines that the high-voltage loop current exceeds the current threshold, it outputs a signal to the disconnection module 111. The disconnection module 111 generates a level signal to the action unit 21 based on the signal output by the control module 112 or directly based on the signal output by the loop current monitoring module 113, cutting off the coil power supply to the contactor 2, thereby opening the contact unit 22 and disconnecting the high-voltage loop 3. After the control module 112 determines that the high-voltage loop current exceeds the current threshold, it simultaneously locks the abnormal signal to ensure that the contactor 2 cannot self-recover; and feeds back a signal to the signal processing module 122, which confirms the abnormal current scenario based on the feedback signal. After the system self-test is normal, the power management module 121 restarts the power supply or the signal processing module 122 sends a reset signal to the control module 112. The control module 112 outputs a reset signal to the disconnect module 111, and the disconnect module 111 outputs a reset level signal to the action unit 21, which re-supply the coil of the contactor 2, causing the contact unit 22 to close, thereby connecting the high voltage circuit.

[0056] More specifically, determining whether the high-voltage circuit current exceeds the current threshold includes the following steps: determining whether the high-voltage circuit current monitored by the circuit current monitoring module 113 exceeds the forward current threshold or the reverse current threshold. If either condition is met, the disconnection module 111 outputs a level signal to the action unit 21 to cut off the coil power supply of the contactor 2, causing the contact unit 22 to open and disconnect the high-voltage circuit; otherwise, no action is taken.

[0057] Optionally, the intelligent control unit 11 may further include a thermistor (NTC) 114, which is connected to the contact unit 22 and used to detect the temperature of the contact unit 22. The temperature signal collected by the thermistor 114 can be output to the control module 112, and then transmitted by the control module 112 to the signal processing module 122; or it can be directly transmitted to the signal processing module 122.

[0058] Please refer to Figure 3 The power grid disconnection unit 12 may further include a communication module 123, and the signal processing module 122 is connected to the power management module 121 and the control module 112 via the communication module 123. The communication module 123 serves to transmit signals between the power management module 121, the control module 112, and the signal processing module 122.

[0059] Optionally, the control module 112 may be a logic control module or a microcontroller, etc., and this application is not limited thereto.

[0060] Optionally, the loop current monitoring module 113 can be implemented using a magnetic induction module. Figure 4A circuit diagram of a specific embodiment of the disconnection module 111 and the loop current monitoring module 113 is shown.

[0061] Specifically, in this embodiment, the loop current monitoring module 113 includes a magnetic induction module 1131. The magnetic induction module 1131 can be a bipolar switched magnetic device or can include multiple unipolar switched magnetic devices. In terms of device type, the magnetic device can be a single type of element such as a switched Hall effect sensor or a switched tunnel magnetoresistive (TMR); or it can be a combined device such as a differential switched Hall effect sensor or a differential switched tunnel magnetoresistive (TMR).

[0062] Furthermore, in this specific embodiment, the disconnecting module 111 includes a trigger 1111, the action unit 21 includes a switch 211 and a contactor coil 212, the first end of the magnetic induction module 1131 collects the high-voltage circuit current, the second end of the magnetic induction module 1131 is connected to the first end of the trigger 1111, the second end of the trigger 1111 is connected to the first end of the switch 211, the second end of the switch 211 is connected to the first end of the contactor coil 212, and the second end of the contactor coil 212 is connected to the contact head unit 22.

[0063] More specifically, the output signal of the switched magnetic device used in the magnetic induction module 1131 generates a rapid switching signal after the detected high-voltage circuit current exceeds the forward current threshold or the reverse current threshold. The rapid switching signal is fixed as an abnormal level signal and output to the switch 211 via the trigger 1111. Upon receiving the abnormal level signal, the switch 211 de-energizes the contactor coil 212, thereby disconnecting the contact unit 22 and cutting off the high-voltage circuit. After being powered on again, the trigger 1111 returns to a normal level signal, restoring power to the contactor coil 212 and resetting the contactor 2.

[0064] Optionally, the trigger 1111 can be a JK trigger, wherein the CP input terminal of the JK trigger is connected to the trigger signal, the J input terminal and the K input terminal are respectively connected to the high-level signal or the low-level signal of the magnetic induction module 1131, and the Q output terminal is connected to the switch 211.

[0065] Optionally, the switch 211 can be a semiconductor switch, including but not limited to MOSFET, IGBT and other switch types.

[0066] Optionally, the loop current monitoring module 113 can be implemented using a high-voltage isolation comparison module. Figure 5 A circuit diagram of another specific embodiment of the disconnection module 111 and the loop current monitoring module 113 is shown.

[0067] Specifically, in this embodiment, the loop current monitoring module 113 includes a high-voltage isolation comparison module 1132 and a current sampling module 1133, the disconnection module 111 includes a trigger 1111, the action unit 21 includes a switch 211 and a contactor coil 212, the current sampling module 1133 is connected in series between the contact unit 22 and the high-voltage loop 3, the first end of the high-voltage isolation comparison module 1132 is connected to the current sampling module 1133, the second end of the high-voltage isolation comparison module 1132 is connected to the first end of the trigger 1111, the second end of the trigger 1111 is connected to the first end of the switch 211, the second end of the switch 211 is connected to the first end of the contactor coil 212, and the second end of the contactor coil 212 is connected to the contact unit 22.

[0068] More specifically, the current sampling module 1133 samples the current in the high-voltage circuit, and the high-voltage isolation comparison module 1132 compares the sampled current with the forward current threshold and the reverse current threshold. If the detected high-voltage circuit current exceeds either the forward current threshold or the reverse current threshold, a fast-change signal is generated. The fast-change signal is fixed as an abnormal level signal and output to the switch 211 via the trigger 1111. Upon receiving the abnormal level signal, the switch 211 de-energizes the contactor coil 212, thereby disconnecting the contact unit 22 and cutting off the high-voltage circuit. After being powered on again, the trigger 1111 returns to a normal level signal, restoring power to the contactor coil 212 and resetting the contactor 2.

[0069] Optionally, the high-voltage isolation comparator module 1132 includes comparator 11321, comparator 11322, and differential amplifier 11323. The first and second terminals of the differential amplifier 11323 are connected to the two ends of the current sampling module 1133. The first and second terminals of comparator 11321 and comparator 11322 are connected to the third terminal of the differential amplifier 11323. The second terminal of comparator 11321 is connected to the first reference voltage V. ref1 The first terminal of comparator 11322 is connected to the second reference voltage V. ref2 The third terminals of comparators 11321 and 11322 are connected to the first terminal of flip-flop 1111. The first reference voltage V... ref1 Indicates the forward current threshold, and the second reference voltage V. ref2 This indicates the reverse current threshold.

[0070] It should be noted that the high-voltage isolation comparator module 1132 can also be selected from other circuit topologies that can achieve high-voltage isolation and comparison functions, and the present invention is not limited thereto.

[0071] Optionally, the current sampling module 1133 can be a shunt, whose resistance changes linearly with the current in the high-voltage circuit.

[0072] It should be noted that the current sampling module 1133 can also be other topologies capable of current sampling, and the present invention is not limited thereto.

[0073] Optionally, the trigger 1111 can be a JK trigger, wherein the CP input terminal of the JK trigger is connected to the trigger signal, the J input terminal and the K input terminal are respectively connected to the high-level signal or the low-level signal of the high-voltage isolation comparator module 1132, and the Q output terminal is connected to the switch 211.

[0074] Optionally, the switch 211 can be a semiconductor switch, including but not limited to MOSFET, IGBT and other switch types.

[0075] More specifically, in the control system of the contactor of the present invention, the magnetic induction module 1131 and the high-voltage isolation comparison module 1132 can exist independently or simultaneously to perform single-channel or multi-channel detection of the current in the high-voltage circuit, thereby improving the reliability of the system's identification of abnormal currents. The control system of the contactor of the present invention can choose to have the disconnecting module 111 send a signal to control the contactor 2 to disconnect after multiple abnormal currents are detected; alternatively, it can choose to have the disconnecting module 111 send a signal to control the contactor 2 to disconnect after any one abnormal current is detected.

[0076] Optionally, the intelligent control unit 11 may further include a high-voltage isolation sampling module 115, which is connected to the contact unit 22 and is used to detect the contact resistance value of the contact unit 22. The contact resistance value collected by the high-voltage isolation sampling module 115 can be output to the control module 112, and then transmitted by the control module 112 to the signal processing module 122; or it can be directly transmitted to the signal processing module 122.

[0077] As an example, the high-voltage isolation sampling module 115 can calculate the contact resistance value by applying a constant current and measuring the voltage drop across the contact unit 22.

[0078] It should be noted that the high-voltage isolation sampling module 115 can also be selected from other circuit topologies that can realize resistance value detection, and the present invention is not limited thereto.

[0079] Furthermore, the control system of the contactor of the present invention can also detect the temperature of the contact unit 22 through the thermistor 114, and simultaneously collect the contact resistance value of the contact unit 22, compare it with preset parameters, and determine the health status of the contactor 2. The collected temperature and contact resistance value of the contact unit 22 can be output to the control module 112. The control module 112 can choose to send a warning message when both the collected contact resistance value is greater than the contact resistance threshold and the collected temperature of the contact unit is greater than the temperature threshold; or it can choose to send a warning message when either of the above two conditions is met.

[0080] Optionally, the collected temperature and contact resistance values ​​of the contact unit 22 can be directly transmitted to the power grid disconnect unit 12 for real-time monitoring and anomaly identification. The power grid disconnect unit 12 can choose to send an alarm message when both the collected contact resistance value is greater than the contact resistance threshold and the collected contact unit temperature is greater than the temperature threshold; alternatively, it can choose to send an alarm message when either of the above two conditions is met.

[0081] The present invention also provides a control method for a contactor, including determining a bidirectional abnormal current.

[0082] For more specific details, please refer to Figure 6 Determining bidirectional abnormal current includes steps S11 to S14.

[0083] Step S11: Monitor the high-voltage circuit current in real time.

[0084] Step S12: Determine whether the high-voltage circuit current is greater than the forward current threshold or the reverse current threshold. If either of the two conditions is met, proceed to step S13; otherwise, return to step S11 and continue monitoring.

[0085] In step S13, the disconnection module 111 outputs a level signal to the action unit 21.

[0086] Step S14: Cut off the power supply to the coil of contactor 2, and disconnect the high-voltage circuit.

[0087] Furthermore, the contactor control method of the present invention also includes,

[0088] Step S15: Determine if the system self-test is normal. If not, proceed to step S18; if yes, proceed to step S16.

[0089] In step S16, the power management module 121 restarts the power supply or sends a reset signal to the control module 112.

[0090] In step S17, the control module 112 outputs a reset signal to the disconnect module 111, and the disconnect module 111 outputs a reset level signal to the action unit 21 to supply power to the coil of the contactor 2 and connect the high voltage circuit.

[0091] Step S18: No action is taken; contactor 2 remains disconnected.

[0092] More specifically, step S18 can also return to step S15 to continuously determine whether the system self-test is normal.

[0093] Furthermore, the contactor control method of the present invention also includes multi-channel abnormal current collaborative determination.

[0094] For more specific details, please refer to Figure 7 The multi-path abnormal current collaborative determination includes steps S21 to S24.

[0095] In step S21, the magnetic induction module 1131 monitors the high-voltage circuit current in real time, and the high-voltage isolation comparison module 1132 monitors the high-voltage circuit current in real time.

[0096] Step S22: Determine whether the high-voltage circuit current monitored by the magnetic induction module 1131 is greater than the forward current threshold or the reverse current threshold, and determine whether the high-voltage circuit current monitored by the high-voltage isolation comparison module 1132 is greater than the forward current threshold or the reverse current threshold. If one of the two conditions is met or both conditions are met simultaneously, proceed to step S23; otherwise, return to step S21 and continue monitoring.

[0097] Step S23: The disconnection module 111 outputs a level signal to the action unit 21.

[0098] Step S24: Cut off the power supply to the coil of contactor 2, and disconnect the high-voltage circuit.

[0099] Furthermore, the contactor control method of the present invention also includes health status monitoring.

[0100] For more specific details, please refer to Figure 8 Health status monitoring includes steps S31 to S33.

[0101] Step S31: Real-time acquisition of the temperature of the contact unit 22 and the contact resistance value of the contact unit 22.

[0102] Step S32: Determine whether the collected contact resistance value is greater than the contact resistance threshold and whether the collected temperature of the contact unit is greater than the temperature threshold. If one or both conditions are met, proceed to step S33; otherwise, return to step S31 and continue monitoring.

[0103] Step S33: Send an alert message.

[0104] The following is combined Figure 9 This invention describes the abnormal current control timing principle of a contactor control system and method. For example... Figure 9 As shown, T1 is the response time of the intelligent control unit in identifying and feeding back the contactor's action unit after an abnormal high current occurs in the high-voltage circuit of the system; T2 is the response time of the contactor's action unit opening after the contactor's action unit responds; T3 is the waiting time for the contactor to reset after the system circuit is de-energized; T4 is the system power supply restart time or reset signal switching time; T5 is the response time of the contactor's action unit resetting; and T6 is the response time of the contactor's contact unit closing.

[0105] It should be understood that although the steps in the flowcharts of the accompanying drawings are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some of the steps in the accompanying drawings may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the sub-steps or stages of other steps.

[0106] Although the present invention has been disclosed above by way of embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A control system for a contactor, characterized in that, It includes an intelligent control unit and a power grid disconnection unit, wherein the intelligent control unit is connected to the power grid disconnection unit and the intelligent control unit is connected to a contactor.

2. The control system for a contactor as described in claim 1, characterized in that, The intelligent control unit includes a disconnection module, a control module, and a loop current monitoring module. The disconnection module is connected to the control module and the contactor's operating unit. The control module is connected to the loop current monitoring module, and the loop current monitoring module is connected to the contactor's contact unit.

3. The control system for a contactor as described in claim 2, characterized in that, The power grid disconnection unit includes a power management module and a signal processing module. The signal processing module is connected to the control module and the power management module. The power management module is connected to one or more modules in the intelligent control unit.

4. The control system for a contactor as described in claim 2, characterized in that, The intelligent control unit includes a thermistor, which is connected to a contact unit.

5. The control system for a contactor as described in claim 3, characterized in that, The power grid disconnection unit includes a communication module, and the signal processing module is connected to the power management module and the control module through the communication module.

6. The control system for a contactor as described in claim 2, characterized in that, The control module is a logic control module or a microcontroller unit.

7. The control system for a contactor as described in claim 2, characterized in that, The loop current monitoring module includes a magnetic induction module, which uses a switched magnetic device. The first end of the magnetic induction module collects the high-voltage loop current, and the second end of the magnetic induction module is connected to the disconnection module.

8. The control system for a contactor as described in claim 2, characterized in that, The circuit current monitoring module includes a high-voltage isolation comparison module and a current sampling module. The current sampling module is connected in series between the contact unit and the high-voltage circuit. The first end of the high-voltage isolation comparison module is connected to the current sampling module, and the second end of the high-voltage isolation comparison module is connected to the disconnection module.

9. A control method for a contactor, characterized in that, A control system for a contactor as described in any one of claims 1-8, comprising: determining a bidirectional abnormal current: Step S11: Monitor the high-voltage circuit current in real time; Step S12: Determine whether the high-voltage circuit current is greater than the forward current threshold or the reverse current threshold. If either of the two conditions is met, proceed to step S13. Otherwise, return to step S11 and continue monitoring; Step S13: The disconnect module outputs a level signal to the action unit; Step S14: Cut off the power supply to the contactor coil, and disconnect the high-voltage circuit.

10. The control method for a contactor as described in claim 9, characterized in that, It also includes, Step S15: Determine if the system self-test is normal. If not, proceed to step S18; if yes, proceed to step S16. Step S16: The power management module restarts power supply or sends a reset signal to the control module; Step S17: The control module outputs a reset signal to the disconnect module, and the disconnect module outputs a reset level signal to the action unit to supply power to the contactor coil and connect the high voltage circuit. Step S18: No action is taken; the contactor remains disconnected.

11. The contactor control method as described in claim 10, characterized in that, It also includes collaborative detection of multiple abnormal currents: Step S21: The magnetic induction module monitors the high-voltage circuit current in real time, and the high-voltage isolation comparison module monitors the high-voltage circuit current in real time. Step S22: Determine whether the high-voltage circuit current monitored by the magnetic induction module is greater than the forward current threshold or the reverse current threshold, and determine whether the high-voltage circuit current monitored by the high-voltage isolation comparison module is greater than the forward current threshold or the reverse current threshold. If one of the two conditions is met or both conditions are met simultaneously, proceed to step S23. Otherwise, return to step S21 and continue monitoring; Step S23: The disconnect module outputs a level signal to the action unit; Step S24: Cut off the power supply to the contactor coil, and disconnect the high-voltage circuit.

12. The contactor control method as described in claim 11, characterized in that, It also includes health status monitoring: Step S31: Real-time acquisition of the temperature of the contact unit and the contact resistance value of the contact unit. Step S32: Determine whether the collected contact resistance value is greater than the contact resistance threshold and whether the collected temperature of the contact unit is greater than the temperature threshold. If one or both conditions are met, proceed to step S33; otherwise, return to step S31 and continue monitoring. Step S33: Send an alert message.

13. A contactor, characterized in that, The control system includes a contactor as described in any one of claims 1-8, wherein the contactor includes an actuating unit and a contact unit, and the actuating unit is connected to the contact unit.

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