CN220019809U - Relay adhesion detection circuit of alternating-current charging pile - Google Patents

Relay adhesion detection circuit of alternating-current charging pile Download PDF

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Publication number
CN220019809U
CN220019809U CN202321155701.3U CN202321155701U CN220019809U CN 220019809 U CN220019809 U CN 220019809U CN 202321155701 U CN202321155701 U CN 202321155701U CN 220019809 U CN220019809 U CN 220019809U
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relay
power
adhesion detection
power relay
signal input
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林键梓
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Shenzhen Energy Efficiency Electrical Technology Co ltd
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Shenzhen Energy Efficiency Electrical Technology Co ltd
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/70—Energy storage systems for electromobility, e.g. batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/7072—Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02T90/10—Technologies relating to charging of electric vehicles
    • Y02T90/12—Electric charging stations

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Abstract

The utility model discloses a relay adhesion detection circuit of an alternating-current charging pile, which comprises a microcontroller and three detection sub-circuits, wherein the alternating-current charging pile is a three-phase alternating-current charging pile and comprises 4 power relay output control circuits, and the power relay output control circuits comprise power relays; the contact input pins of the first power relay are connected with zero lines, and the contact input pins of the other three power relays are respectively connected with three firing lines; the first signal input ends of the three detection sub-circuits are respectively connected with the contact output pins of the other three power relays, the second signal input ends of the three detection sub-circuits are respectively connected with the contact output pins of the first power relay, and the detection signal output ends of the three detection sub-circuits are respectively connected with the detection signal input pins corresponding to the microcontroller. The utility model can conveniently detect the adhesion fault of the relay of the three-phase alternating current charging pile.

Description

Relay adhesion detection circuit of alternating-current charging pile
[ technical field ]
The utility model relates to an alternating-current charging pile, in particular to a relay adhesion detection circuit of the alternating-current charging pile.
[ background Art ]
The function of the alternating-current charging pile is to safely and reliably convey the commercial power to the vehicle-mounted OBC at the vehicle end, the relay of the alternating-current charging pile is a key switch from the commercial power to the vehicle-mounted OBC, and the working state of the relay needs to be monitored in order to ensure the safety and the reliability of the relay.
The utility model has disclosed a kind of application number 202211615955.9 and charged the pile relay adhesion detection circuit, relate to the adhesion detection control technical field of the relay, include main power relay output control circuit and relay adhesion detection circuit; the relay adhesion detection circuit comprises a capacitor C5, a resistor R11, a resistor R12, a diode D3, a resistor R13, a capacitor C6, a photoelectric coupler U1, +3.3V voltage end, an L_OUT end and an N_OUT end; the main POWER relay output control circuit comprises a diode D1, a diode D2, a main POWER relay K1, a main POWER relay K2, a triode Q1, a triode Q2, a capacitor C1, a capacitor C2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, an OUT_POWER1 end, an OUT_POWER2 end, an L_IN end, an N_IN end, an L_OUT end, an N_OUT end and a +12V voltage end; according to the utility model, the relay with the auxiliary contact is replaced by the relay adhesion detection circuit, so that the cost of the charging pile is reduced, and the design volume is reduced; the optical coupler is utilized to realize signal transmission and electrical isolation, and the circuit structure is simple, so that reliable safety isolation can be ensured. However, the relay adhesion detection circuit of the alternating current charging pile can only be used for single-phase alternating current input charging piles, but cannot be used for three-phase alternating current input charging piles.
[ summary of the utility model ]
The utility model aims to provide a relay adhesion detection circuit suitable for a three-phase alternating current charging pile.
In order to solve the technical problem, the utility model adopts the technical scheme that the relay adhesion detection circuit of the alternating-current charging pile comprises a microcontroller and three relay adhesion detection sub-circuits, wherein the alternating-current charging pile is a three-phase alternating-current charging pile, the three-phase alternating-current charging pile comprises 4 power relay output control circuits, and the power relay output control circuits comprise power relays; the contact input pin of the first power relay is connected with the zero line, the contact input pin of the second power relay is connected with the first fire wire, the contact input pin of the third power relay is connected with the second fire wire, and the contact input pin of the fourth power relay is connected with the third fire wire; the first signal input end of the first relay adhesion detection subcircuit is connected with the contact output pin of the second power relay, the first signal input end of the second relay adhesion detection subcircuit is connected with the contact output pin of the third power relay, and the first signal input end of the third relay adhesion detection subcircuit is connected with the contact output pin of the fourth power relay; the second signal input ends of the three relay adhesion detection subcircuits are connected with the contact output pins of the first power relay, and the detection signal output ends of the three relay adhesion detection subcircuits are respectively connected with the detection signal input pins corresponding to the microcontroller.
The relay adhesion detection circuit of the alternating-current charging pile comprises a power relay output control circuit, wherein the power relay output control circuit comprises a driving circuit, the driving circuit comprises a triode and a driving signal input pin, and a first end of a power relay coil is connected with a relay power supply; the second end of the power relay coil is connected with the collector electrode of the triode, the emitter electrode of the triode is grounded, and the base electrode of the triode is connected with a corresponding driving signal input pin.
The relay adhesion detection circuit of the alternating-current charging pile comprises a power relay output control circuit, wherein the power relay output control circuit comprises a freewheeling diode, the driving circuit comprises a voltage dividing circuit, the voltage dividing circuit is connected between a corresponding driving signal input pin and the ground, and the base electrode of the triode is connected with the voltage signal output end of the voltage dividing circuit; the cathode of the freewheel diode is connected with the first end of the power relay coil, and the anode of the freewheel diode is connected with the second end of the power relay coil.
The relay adhesion detection circuit of the alternating-current charging pile comprises an optocoupler, a current-limiting resistor and a pull-down resistor, wherein the first end of the current-limiting resistor is a first signal input end of the relay adhesion detection subcircuit, the second end of the current-limiting resistor is connected with an anode of an optocoupler light-emitting diode, and the anode of the optocoupler light-emitting diode is a second signal input end of the relay adhesion detection subcircuit; the collector of the optocoupler phototriode is connected with an auxiliary power supply, the emitter of the optocoupler phototriode is grounded through a pull-down resistor, and the emitter of the optocoupler phototriode is a detection signal output end of the relay adhesion detection subcircuit.
The relay adhesion detection circuit of the alternating current charging pile comprises a diode, wherein the cathode of the diode is connected with the anode of the light-emitting diode, and the anode of the diode is connected with the second end of the current-limiting resistor.
The adhesion detection circuit of the power relay of the alternating current charging pile is suitable for detecting adhesion faults of the three-phase alternating current charging pile relay.
[ description of the drawings ]
The utility model will be described in further detail with reference to the drawings and the detailed description.
Fig. 1 is a circuit diagram of a relay adhesion detection circuit of a three-phase ac charging stake according to an embodiment of the present utility model.
Detailed description of the preferred embodiments
The structure of the relay adhesion detection circuit of the three-phase alternating-current charging pile is shown in fig. 1, and the relay adhesion detection circuit comprises a microcontroller (not shown in the figure) and three relay adhesion detection sub-circuits, wherein the three-phase alternating-current charging pile comprises 4 power relay output control circuits.
The first power relay output control circuit includes a power relay K1, a freewheel diode D1, and a first drive circuit. The first driving circuit comprises a triode Q1 and a voltage dividing circuit formed by connecting a resistor R1 and a resistor R2 in series. The first end of the coil of the power relay K1 is connected with a relay power supply +12V. The second end of the power relay coil is connected with the collector electrode of the triode Q1, and the emitter electrode of the triode Q1 is grounded. The voltage dividing circuit formed by serially connecting the resistor R1 and the resistor R2 is connected between the first driving signal input pin RLY_1 and the ground, and the base electrode of the triode Q1 is connected with the voltage signal output end (the connection point of the resistor R1 and the resistor R2) of the voltage dividing circuit. The cathode of the freewheeling diode D1 is connected with the first end of the power relay K1 coil, and the anode is connected with the second end of the power relay coil. The contact input pin N_IN of the first power relay is connected with the zero line of the three-phase alternating current charging pile power supply
The second power relay output control circuit includes a power relay K2, a freewheel diode D2, and a second drive circuit. The second driving circuit comprises a triode Q2 and a voltage dividing circuit formed by serially connecting a resistor R3 and a resistor R4. The first end of the power relay K2 coil is connected with a relay power supply +12V. The second end of the power relay coil is connected with the collector electrode of the triode Q2, and the emitter electrode of the triode Q2 is grounded. The voltage dividing circuit formed by serially connecting the resistor R3 and the resistor R4 is connected between the second driving signal input pin RLY_2 and the ground, and the base electrode of the triode Q2 is connected with the voltage signal output end (the connection point of the resistor R3 and the resistor R4) of the voltage dividing circuit. The cathode of the freewheel diode D2 is connected with the first end of the power relay K2 coil, and the anode of the freewheel diode D2 is connected with the second end of the power relay K2 coil. The contact input pin L1_IN of the second power relay is connected with the first phase live wire of the three-phase alternating current charging pile power supply.
The third power relay output control circuit comprises a power relay K3, a freewheel diode D3 and a third driving circuit. The third driving circuit comprises a triode Q3 and a voltage dividing circuit formed by serially connecting a resistor R7 and a resistor R8. The first end of the power relay K3 coil is connected with a relay power supply +12V. The second end of the power relay coil is connected with the collector electrode of the triode Q3, and the emitter electrode of the triode Q3 is grounded. The voltage dividing circuit formed by serially connecting the resistor R7 and the resistor R8 is connected between the third driving signal input pin RLY_3 and the ground, and the base electrode of the triode Q3 is connected with the voltage signal output end (the connection point of the resistor R7 and the resistor R8) of the voltage dividing circuit. The cathode of the freewheel diode D3 is connected with the first end of the power relay K3 coil, and the anode of the freewheel diode D3 is connected with the second end of the power relay K3 coil. The contact input pin L2_IN of the third power relay is connected with the second phase live wire of the three-phase alternating current charging pile power supply.
The fourth power relay output control circuit includes a power relay K4, a freewheel diode D4, and a fourth drive circuit. The fourth driving circuit comprises a triode Q4 and a voltage dividing circuit formed by serially connecting a resistor R11 and a resistor R12. The first end of the power relay K4 coil is connected with a relay power supply +12V. The second end of the power relay coil is connected with the collector electrode of the triode Q4, and the emitter electrode of the triode Q4 is grounded. The voltage dividing circuit formed by serially connecting the resistor R11 and the resistor R12 is connected between the fourth driving signal input pin RLY_4 and the ground, and the base electrode of the triode Q4 is connected with the voltage signal output end (the connection point of the resistor R11 and the resistor R12) of the voltage dividing circuit. The cathode of the freewheel diode D4 is connected with the first end of the power relay K4 coil, and the anode of the freewheel diode D4 is connected with the second end of the power relay K4 coil. The contact input pin L3_IN of the fourth power relay is connected with the third phase live wire of the three-phase alternating current charging pile power supply
The first relay adhesion detection sub-circuit comprises a first optocoupler OT1, a current limiting resistor R5, a diode D3 and a pull-down resistor R6. The first end of the current limiting resistor R5 is a first signal input end of the relay adhesion detection subcircuit and is connected with a contact output pin L1_OUT of the second power relay K2. The cathode of the diode D3 is connected with the anode of the photo-coupler OT1 light-emitting diode, the anode of the diode D3 is connected with the second end of the current-limiting resistor R5, and the cathode of the first photo-coupler OT1 light-emitting diode is connected with the contact output pin N_OUT of the first power relay K1. The collector of the first optical coupler OT1 phototriode is connected with an auxiliary power supply +3.3V, the emitter is grounded through a pull-down resistor R6, and the emitter of the first optical coupler OT1 phototriode is used as a detection signal output end of a first relay adhesion detection subcircuit to be connected with a first detection signal input pin RLY_ON_DET1 of the microcontroller.
The second relay adhesion detection sub-circuit comprises a second optocoupler OT2, a current limiting resistor R9, a diode D5 and a pull-down resistor R10. The second end of the current limiting resistor R9 is a second signal input end of the relay adhesion detection subcircuit and is connected with a contact output pin L2_OUT of the third power relay K3. The cathode of the diode D5 is connected with the anode of the photo-coupler OT2 light-emitting diode, the anode of the diode D5 is connected with the second end of the current-limiting resistor R9, and the cathode of the second photo-coupler OT2 light-emitting diode is connected with the contact output pin N_OUT of the first power relay K1. The collector of the second optical coupler OT2 phototriode is connected with an auxiliary power supply +3.3V, the emitter is grounded through a pull-down resistor R10, and the emitter of the second optical coupler OT2 phototriode is used as a detection signal output end of a second relay adhesion detection subcircuit to be connected with a second detection signal input pin RLY_ON_DET2 of the microcontroller.
The third relay adhesion detection sub-circuit comprises a third optocoupler OT3, a current limiting resistor R13, a diode D7 and a pull-down resistor R14. The first end of the current limiting resistor R13 is used as a second signal input end of the third relay adhesion detection subcircuit and is connected with a contact output pin L3_OUT of the fourth power relay K4. The cathode of the diode D7 is connected with the anode of the third optocoupler OT3 light-emitting diode, the anode of the diode D7 is connected with the second end of the current-limiting resistor R13, and the cathode of the third optocoupler OT3 light-emitting diode is connected with the contact output pin N_OUT of the first power relay K1. The collector of the third optocoupler OT3 phototriode is connected with an auxiliary power supply +3.3V, the emitter is grounded through a pull-down resistor R14, and the emitter of the third optocoupler OT3 phototriode is used as a detection signal output end of a third relay adhesion detection subcircuit to be connected with a third detection signal input pin RLY_ON_DET3 of the microcontroller.
The detection working process of the power relay adhesion detection circuit of the three-phase alternating-current charging pile comprises the following steps:
the first step: the four power relays K1, K2, K3 and K4 are not given control signals, and in a normal state, the power relays are turned off.
If the first power relay K1 and the second power relay K2 are adhered together, a voltage is generated between the 1 pin and the 2 pin of the light emitting diode of the first optocoupler OT1, the light emitting diode of the first optocoupler OT1 is conducted, the first detection signal input pin rly_on_det1 of the Microcontroller (MCU) obtains a high level, and the MCU determines that the adhesion fault exists in the power relay.
If the first power relay K1 and the third power relay K3 are adhered at the same time, a voltage is generated between the 1 pin and the 2 pin of the second optical coupler OT2, the light emitting diode of the second optical coupler OT2 is conducted, the second detection signal input pin rly_on_det2 of the Microcontroller (MCU) obtains a high level, and the MCU determines that the adhesion fault exists in the power relay.
If the first power relay K1 and the fourth power relay K4 are adhered at the same time, a voltage is generated between the 1 pin and the 2 pin of the third optocoupler OT3, the light emitting diode of the third optocoupler OT3 is conducted, the third detection signal input pin rly_on_det3 of the Microcontroller (MCU) obtains a high level, and the MCU determines that the adhesion fault exists in the power relay.
And a second step of: the power relays K2, K3 and K4 are closed.
If the power relay K1 is stuck, voltages are generated between the pins 1 and 2 of the optocouplers OT1, OT2 and OT3, the optocouplers are turned ON, the rly_on_det1, rly_on_det2 and rly_on_det3 are high-level, and the MCU determines that the power relay K1 is stuck and fails.
If the power relay K1 is not adhered, no voltage exists between pins 1 and 2 of the optocouplers OT1, OT2 and OT3, the optocouplers OT1, OT2 and OT3 are not conducted, detection signal input pins rly_on_det1, rly_on_det2 and rly_on_det3 of the controller (MCU) are at low level, and the MCU determines that the power relay K1 is normal.
And a third step of: the power relays K2, K3 and K4 are opened, and the power relay K1 is closed.
If the power relays K2, K3, and K4 are stuck, voltages are generated between pins 1 and 2 of the optocouplers OT1, OT2, and OT3, the optocouplers OT1, OT2, and OT3 are turned ON, the detection signal input pins rly_on_det1, rly_on_det2, and rly_on_det3 of the controller (MCU) obtain high levels, and the MCU determines that the power relays K2, K3, and K4 have stuck faults.
If the power relays K2, K3, K4 are not adhered, there is no voltage between the two ends 1, 2 of the optocouplers OT1, OT2, OT3, and the detection signal input pins rly_on_det1, rly_on_det2, rly_on_det3 of the controller (MCU) are low level, and the MCU determines that the power relays K2, K3, K4 are normal.
Fourth step: through the three steps, the optocouplers output low level, and then the power relays K2, K3 and K4 can be closed to enter normal charging logic.
The adhesion detection circuit of the power relay of the three-phase alternating current charging pile can conveniently detect adhesion faults of the relay of the three-phase alternating current charging pile, can monitor the state of the relay in real time, can detect any one of the four relays to adhere, and has short detection time. Compared with a relay with a self-adhesive detection winding, the detection circuit does not need the relay with the self-adhesive detection winding, and has low cost and small relay size.

Claims (5)

1. The relay adhesion detection circuit of the alternating-current charging pile is characterized by comprising a microcontroller and three relay adhesion detection sub-circuits, wherein the alternating-current charging pile is a three-phase alternating-current charging pile, the three-phase alternating-current charging pile comprises 4 power relay output control circuits, and the power relay output control circuits comprise power relays; the contact input pin of the first power relay is connected with the zero line, the contact input pin of the second power relay is connected with the first fire wire, the contact input pin of the third power relay is connected with the second fire wire, and the contact input pin of the fourth power relay is connected with the third fire wire; the first signal input end of the first relay adhesion detection subcircuit is connected with the contact output pin of the second power relay, the first signal input end of the second relay adhesion detection subcircuit is connected with the contact output pin of the third power relay, and the first signal input end of the third relay adhesion detection subcircuit is connected with the contact output pin of the fourth power relay; the second signal input ends of the three relay adhesion detection subcircuits are connected with the contact output pins of the first power relay, and the detection signal output ends of the three relay adhesion detection subcircuits are respectively connected with the detection signal input pins corresponding to the microcontroller.
2. The relay adhesion detection circuit of an ac charging stake of claim 1, wherein the power relay output control circuit includes a drive circuit including a transistor, a drive signal input pin, a first terminal of the power relay coil connected to a relay power source; the second end of the power relay coil is connected with the collector electrode of the triode, the emitter electrode of the triode is grounded, and the base electrode of the triode is connected with a corresponding driving signal input pin.
3. The relay adhesion detection circuit of an ac charging pile according to claim 2, wherein the power relay output control circuit comprises a freewheeling diode, the driving circuit comprises a voltage dividing circuit, the voltage dividing circuit is connected between a corresponding driving signal input pin and the ground, and a base electrode of the triode is connected with a voltage signal output end of the voltage dividing circuit; the cathode of the freewheel diode is connected with the first end of the power relay coil, and the anode of the freewheel diode is connected with the second end of the power relay coil.
4. The relay adhesion detection circuit of the alternating current charging pile according to claim 1, wherein the relay adhesion detection sub-circuit comprises an optocoupler, a current limiting resistor and a pull-down resistor, a first end of the current limiting resistor is a first signal input end of the relay adhesion detection sub-circuit, a second end of the current limiting resistor is connected with an anode of an optocoupler light emitting diode, and an anode of the optocoupler light emitting diode is a second signal input end of the relay adhesion detection sub-circuit; the collector of the optocoupler phototriode is connected with an auxiliary power supply, the emitter of the optocoupler phototriode is grounded through a pull-down resistor, and the emitter of the optocoupler phototriode is a detection signal output end of the relay adhesion detection subcircuit.
5. The relay adhesion detection circuit of an ac charging stake of claim 4, wherein the relay adhesion detection subcircuit includes a diode, a cathode of the diode being coupled to an anode of the light emitting diode, an anode of the diode being coupled to a second end of the current limiting resistor.
CN202321155701.3U 2023-05-15 2023-05-15 Relay adhesion detection circuit of alternating-current charging pile Active CN220019809U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202321155701.3U CN220019809U (en) 2023-05-15 2023-05-15 Relay adhesion detection circuit of alternating-current charging pile

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202321155701.3U CN220019809U (en) 2023-05-15 2023-05-15 Relay adhesion detection circuit of alternating-current charging pile

Publications (1)

Publication Number Publication Date
CN220019809U true CN220019809U (en) 2023-11-14

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Application Number Title Priority Date Filing Date
CN202321155701.3U Active CN220019809U (en) 2023-05-15 2023-05-15 Relay adhesion detection circuit of alternating-current charging pile

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