Charging pile zero line and live line relay detection circuit and charging pile

Abstract

The utility model provides a charging pile zero line and live line relay detection circuit and a charging pile. The circuit is used for detecting faults of a first relay and a second relay, the first end of the first relay is connected with a live wire, and the first end of the second relay is connected with a null line; the second end of the first relay and the second end of the second relay are used for supplying power to a load; the first input end of the relay detection circuit is connected with the second end of the first relay, and the second input end of the relay detection circuit is connected with the second end of the second relay; the circuit comprises an optocoupler module, a first resistor and a second resistor, the first input end of the optocoupler module is connected with the first input end of the relay detection circuit through a first resistor, the second input end of the optocoupler module is connected with the second input end of the relay detection circuit through a second resistor, and the output end of the optocoupler module is used for outputting a detection signal. The optocoupler module is connected with the two relays in series, faults of the two relays can be detected at the same time, and the circuit structure is simple.

Description

Technical Field

[0001] The utility model relates to the technical field of charging piles, and in particular to a charging pile neutral line and live line relay detection circuit and a charging pile. Background Art

[0002] With the development of electric vehicles, charging piles are used to charge electric vehicles, and the demand is increasing. The neutral and live wires of the charging pile are usually connected in series with two AC relays to control the output of the charging pile. When the AC relay has adhesion or short circuit faults, it will affect the normal use of the charging pile and even cause safety accidents. Therefore, it is necessary to perform fault detection on the AC relay in the charging pile.

[0003] In the prior art, detection circuits are usually provided for two AC relays respectively to detect faults of the two AC relays respectively, and the circuits are complicated. Utility Model Content

[0004] The embodiment of the utility model provides a charging pile neutral line live line relay detection circuit and a charging pile, so as to solve the problem that two detection circuits are required in the prior art to perform fault detection on the AC relay respectively, resulting in complex circuits.

[0005] In a first aspect, an embodiment of the utility model provides a charging pile neutral line live line relay detection circuit, which is used to detect faults of a first relay and a second relay, wherein a first end of the first relay is connected to the live line, and a first end of the second relay is connected to the neutral line; a second end of the first relay and a second end of the second relay are used to supply power to a load; a first input end of the relay detection circuit is connected to a second end of the first relay, and a second input end of the relay detection circuit is connected to a second end of the second relay;

[0006] The relay detection circuit comprises: an optical coupling module, a first resistor and a second resistor;

[0007] The first input end of the optocoupler module is connected to the first input end of the relay detection circuit through a first resistor, the second input end of the optocoupler module is connected to the second input end of the relay detection circuit through a second resistor, and the output end of the optocoupler module is used to output a detection signal.

[0008] Optionally, the charging pile neutral wire and live wire relay detection circuit further includes: a first capacitor and a first switch;

[0009] The first capacitor and the first switch are connected in series between the second input terminal of the relay detection circuit and the first ground terminal.

[0010] Optionally, the first capacitor is a Y capacitor.

[0011] Optionally, the optical coupler module includes: an optical coupler and a third resistor;

[0012] The anode of the optocoupler is connected to the first input end of the optocoupler module, the cathode of the optocoupler is connected to the second input end of the optocoupler module, the collector of the optocoupler is connected to a DC power supply, and the emitter of the optocoupler is respectively connected to the first end of the third resistor and the output end of the optocoupler module;

[0013] The second end of the third resistor is connected to the second ground end.

[0014] Optionally, the optical coupling module further includes: a first diode;

[0015] The anode of the first diode is connected to the cathode of the optocoupler, and the cathode of the first diode is connected to the anode of the optocoupler.

[0016] Optionally, the optical coupling module further includes: a second capacitor;

[0017] The second capacitor is connected in parallel with the third resistor.

[0018] Optionally, the optical coupling module further includes: a fourth resistor;

[0019] The first end of the fourth resistor is connected to the emitter of the optical coupler and the first end of the third resistor respectively, and the second end of the fourth resistor is connected to the output end of the optical coupler module.

[0020] Optionally, the optical coupling module further includes: a third capacitor;

[0021] The first end of the third capacitor is connected to the second end of the fourth resistor and the output end of the optical coupling module respectively, and the second end of the third capacitor is connected to the second ground end.

[0022] Optionally, the optical coupling module further includes: a fourth capacitor;

[0023] A first end of the fourth capacitor is connected to the collector of the optocoupler and the DC power supply, and a second end of the fourth capacitor is connected to the second ground end.

[0024] In a second aspect, an embodiment of the utility model provides a charging pile, including the charging pile neutral line and live line relay detection circuit provided in the first aspect of the embodiment of the utility model.

[0025] The embodiment of the utility model provides a charging pile neutral line live line relay detection circuit and a charging pile. The circuit is used to detect the fault of the first relay and the second relay, wherein the first end of the first relay is connected to the live line, and the first end of the second relay is connected to the neutral line; the second end of the first relay and the second end of the second relay are used to power the load; the first input end of the relay detection circuit is connected to the second end of the first relay, and the second input end of the relay detection circuit is connected to the second end of the second relay; the above circuit includes: an optocoupler module, a first resistor and a second resistor; the first input end of the optocoupler module is connected to the first input end of the relay detection circuit through the first resistor, the second input end of the optocoupler module is connected to the second input end of the relay detection circuit through the second resistor, and the output end of the optocoupler module is used to output a detection signal. In the embodiment of the utility model, the optocoupler module is connected in series with two relays, so that the faults of the two relays can be detected at the same time, and the circuit structure is simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0027] Figure 1 This is a circuit structure diagram of a charging pile neutral line and live line relay detection circuit provided by an embodiment of the utility model;

[0028] Figure 2 This is a circuit structure diagram of another charging pile neutral line and live line relay detection circuit provided by an embodiment of the utility model;

[0029] Figure 3 This is a circuit schematic diagram of an optocoupler module provided in an embodiment of the utility model;

[0030] Figure 4 This is a circuit schematic diagram of another optocoupler module provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0031] In order to enable people in the technical field to better understand the present solution, the technical solution in the embodiment of the present solution will be clearly described below in conjunction with the drawings in the embodiment of the present solution. Obviously, the described embodiment is an embodiment of a part of the present solution, not all of the embodiments. Based on the embodiments in the present solution, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present solution.

[0032] The term "including" and any other variations in the specification and claims of this solution and the above drawings mean "including but not limited to", and is intended to cover non-exclusive inclusions and is not limited to the examples listed in the text. In addition, the terms "first" and "second" are used to distinguish different objects, not to describe a specific order.

[0033] The following is a detailed description of the implementation of the present invention in conjunction with the specific drawings:

[0034] Figure 1 A schematic diagram of a charging pile neutral line and live line relay detection circuit provided by the utility model; Figure 1 , the circuit is used to detect faults of the first relay KT1 and the second relay KT2, wherein the first end of the first relay KT1 is connected to the live wire L, and the first end of the second relay KT2 is connected to the neutral wire N; the second end of the first relay KT1 and the second end of the second relay KT2 are used to supply power to the load; the first input end of the relay detection circuit is connected to the second end of the first relay KT1, and the second input end of the relay detection circuit is connected to the second end of the second relay KT2;

[0035] refer to Figure 1 , the relay detection circuit comprises: an optical coupling module 11, a first resistor R1 and a second resistor R2;

[0036] The first input end of the optocoupler module 11 is connected to the first input end of the relay detection circuit through the first resistor R1, the second input end of the optocoupler module 11 is connected to the second input end of the relay detection circuit through the second resistor R2, and the output end of the optocoupler module 11 is used to output a detection signal.

[0037] In the embodiment of the utility model, the input end of the optical coupling module 11 is connected in series with the first relay KT1 and the second relay KT2. By controlling the first relay KT1 and the second relay KT2 to open or close, fault detection of the two relays (the first relay KT1 and the second relay KT2) can be realized at the same time.

[0038] Specifically, the circuit schematic diagram of the optocoupler module 11 is shown in Figure 3. When the optocoupler U1 is turned on, the detection signal is at a high level; when the optocoupler U1 is turned off, the detection signal is at a low level.

[0039] The second relay KT2 is controlled to be disconnected, and the first relay KT1 is controlled to be closed; if the detection signal is at a high level, it means that the optocoupler U1 is turned on, which means that the second relay KT2 is stuck, so that a path is formed between the neutral line N and the live line L; at this time, the first relay KT1 is controlled to be disconnected, if the detection signal is still at a high level, it means that the first relay KT1 and the second relay KT2 are stuck at the same time; if the detection signal becomes a low level after the first relay KT1 is disconnected, it means that only the second relay KT2 is stuck, and the first relay KT1 is not stuck.

[0040] The first relay KT1 is controlled to be disconnected, and the second relay KT2 is controlled to be closed. If the detection signal is at a high level, it means that the optocoupler U1 is turned on, and the first relay KT1 is stuck. At this time, the second relay KT2 is controlled to be disconnected. If the detection signal is still at a high level, it means that the first relay KT1 and the second relay KT2 are stuck at the same time. If the detection signal becomes a low level after the second relay KT2 is disconnected, it means that the second relay KT2 is not stuck, and only the first relay KT1 is stuck.

[0041] The above detection logic is only an embodiment, and the specific detection logic includes but is not limited to the above, which can be set according to actual application requirements. The above detection logic is a conventional technical means, and this application does not protect the above detection logic.

[0042] In one possible implementation, reference Figure 2 , the above charging pile neutral line live line relay detection circuit may also include: a first capacitor C1 and a first switch K1;

[0043] The first capacitor C1 and the first switch K1 are connected in series between the second input terminal of the relay detection circuit and the first ground terminal.

[0044] The present application further provides a first capacitor C1 and a first switch K1, and the first switch K1 is used to control the access of the first capacitor C1. For example, when the above detection logic is used to perform relay adhesion detection, the first switch K1 is controlled to be disconnected, and the first capacitor C1 is not connected.

[0045] At the same time, the relay disconnection can be detected through the first capacitor C1 and the first switch K1. Specifically, the first switch K1 can be closed to connect the first capacitor C1, forming a path between the live wire L-first relay KT1-first resistor R1-optical coupling module 11-second resistor R2-first capacitor C1-first switch K1-first grounding terminal; close the first relay KT1 and disconnect the second relay KT2. If the detection signal is high, it means that there is no disconnection fault in the first relay KT1; if the detection signal is low, it means that there is a disconnection fault in the first relay KT1.

[0046] Furthermore, the first relay KT1 is closed and the second relay KT2 is disconnected, and when the detection signal is at a high level, the first relay KT1 is disconnected. If the detection signal is still at a high level, it can be determined that the first relay KT1 has adhesion; if the detection signal switches to a low level, it indicates that the first relay KT1 has neither adhesion nor circuit breakage. Based on the above, the adhesion and circuit breakage fault detection of the first relay KT1 can be realized at the same time.

[0047] Exemplarily, the first ground terminal may be a chassis ground.

[0048] In a possible implementation, the first switch K1 may be a relay.

[0049] Since the AC voltage is relatively high, the first switch K1 may also be a relay to improve the safety of the circuit.

[0050] In a possible implementation, the first capacitor C1 may be a Y capacitor.

[0051] In the embodiment of the utility model, the first capacitor C1 can be a Y capacitor. The Y capacitor is a safety capacitor with high voltage resistance and can adapt to harsh environmental conditions, thereby effectively improving the safety of the circuit and ensuring personal safety.

[0052] In one possible implementation, reference Figure 3 , the optical coupling module 11 may include: an optical coupling U1 and a third resistor R3;

[0053] The anode of the optocoupler U1 is connected to the first input end of the optocoupler module 11, the cathode of the optocoupler U1 is connected to the second input end of the optocoupler module 11, the collector of the optocoupler U1 is connected to the DC power supply VCC, and the emitter of the optocoupler U1 is respectively connected to the first end of the third resistor R3 and the output end of the optocoupler module 11;

[0054] The second end of the third resistor R3 is connected to the second ground end.

[0055] In the embodiment of the utility model, the third resistor R3 is connected in series between the collector of the optocoupler U1 and the second ground terminal, so that the optocoupler U1 outputs a high level when it is turned on, and outputs a low level when it is turned off.

[0056] The optical coupling module 11 includes but is not limited to Figure 3 As shown in the connection relationship, the third resistor R3 can also be connected in series between the DC power supply VCC and the collector of the optocoupler U1, and the emitter of the optocoupler U1 is connected to the output end of the optocoupler module 11, which will not be described in detail here.

[0057] In one possible implementation, reference Figure 4 , the optical coupling module 11 may further include: a first diode D1;

[0058] The anode of the first diode D1 is connected to the cathode of the optocoupler U1 , and the cathode of the first diode D1 is connected to the anode of the optocoupler U1 .

[0059] Since the first relay KT1 and the second relay KT2 in this solution are arranged between the AC neutral and live wires (L and N), which are AC power supplies, a reverse voltage will be input to the input end of the optocoupler U1. The first diode D1 is reversely connected in parallel with the diode of the optocoupler U1, and is turned on when the optocoupler U1 is input with a reverse voltage, thereby preventing the reverse voltage from damaging the optocoupler U1, and improving the safety and stability of the circuit.

[0060] In one possible implementation, reference Figure 4 , the optical coupling module 11 may further include: a second capacitor C2;

[0061] The second capacitor C2 is connected in parallel with the third resistor R3.

[0062] The second resistor R2 and the third resistor R3 are connected in parallel for filtering.

[0063] In one possible implementation, reference Figure 4 , the optical coupling module 11 may further include: a fourth resistor R4;

[0064] A first end of the fourth resistor R4 is connected to the emitter of the optical coupler U1 and a first end of the third resistor R3 , respectively. A second end of the fourth resistor R4 is connected to the output end of the optical coupler module 11 .

[0065] The fourth resistor R4 is connected between the emitter of the optocoupler U1 and the output end of the optocoupler module 11 and is used for buffering to improve the stability of the detection signal.

[0066] In one possible implementation, reference Figure 4 , the optical coupling module 11 may further include: a third capacitor C3;

[0067] A first end of the third capacitor C3 is connected to the second end of the fourth resistor R4 and the output end of the optical coupling module 11 respectively, and a second end of the third capacitor C3 is connected to the second ground end.

[0068] The third capacitor C3 is arranged at the output end of the optical coupling module 11 and is used for filtering to improve the stability of the detection signal.

[0069] In one possible implementation, reference Figure 4 , the optical coupling module 11 may further include: a fourth capacitor C4;

[0070] A first end of the fourth capacitor C4 is connected to the collector of the optical coupler U1 and the DC power supply VCC, and a second end of the fourth capacitor C4 is connected to the second ground end.

[0071] The fourth capacitor C4 is connected between the DC power supply VCC and the second ground terminal, which can effectively reduce power supply noise and other interference, improve the quality and stability of the detection signal, and effectively improve the stability and reliability of the circuit.

[0072] Corresponding to the above embodiments, the embodiments of the utility model also provide a charging pile, including the charging pile neutral wire and live wire relay detection circuit provided by any of the above embodiments, and having the advantages of any of the above charging pile neutral wire and live wire relay detection circuits, which will not be described in detail here.

[0073] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A charging pile neutral line live line relay detection circuit, characterized in that: Used to detect faults of a first relay and a second relay, wherein a first end of the first relay is connected to a live wire, and a first end of the second relay is connected to a neutral wire; a second end of the first relay and a second end of the second relay are used to supply power to a load; a first input end of the relay detection circuit is connected to a second end of the first relay, and a second input end of the relay detection circuit is connected to a second end of the second relay; The relay detection circuit comprises: an optical coupling module, a first resistor and a second resistor; The first input end of the optocoupler module is connected to the first input end of the relay detection circuit through the first resistor, the second input end of the optocoupler module is connected to the second input end of the relay detection circuit through the second resistor, and the output end of the optocoupler module is used to output a detection signal.

2. The charging pile neutral line live line relay detection circuit according to claim 1, characterized in that: The charging pile neutral line live line relay detection circuit also includes: a first capacitor and a first switch; The first capacitor and the first switch are connected in series between the second input terminal of the relay detection circuit and the first ground terminal.

3. The charging pile neutral line live line relay detection circuit as claimed in claim 2, characterized in that: The first capacitor is a Y capacitor.

4. The charging pile neutral line and live line relay detection circuit according to any one of claims 1 to 3, characterized in that: The optical coupling module includes: an optical coupling and a third resistor; The anode of the optical coupler is connected to the first input end of the optical coupler module, the cathode of the optical coupler is connected to the second input end of the optical coupler module, the collector of the optical coupler is connected to a DC power supply, and the emitter of the optical coupler is respectively connected to the first end of the third resistor and the output end of the optical coupler module; The second end of the third resistor is connected to the second ground end.

5. The charging pile neutral line live line relay detection circuit as claimed in claim 4, characterized in that: The optical coupling module further includes: a first diode; The anode of the first diode is connected to the cathode of the optocoupler, and the cathode of the first diode is connected to the anode of the optocoupler.

6. The charging pile neutral line and live line relay detection circuit according to claim 4, characterized in that: The optical coupling module further includes: a second capacitor; The second capacitor is connected in parallel with the third resistor.

7. The charging pile neutral line and live line relay detection circuit according to claim 4, characterized in that: The optical coupling module further includes: a fourth resistor; The first end of the fourth resistor is connected to the emitter of the optical coupler and the first end of the third resistor respectively, and the second end of the fourth resistor is connected to the output end of the optical coupler module.

8. The charging pile neutral line and live line relay detection circuit according to claim 7, characterized in that: The optical coupling module further includes: a third capacitor; The first end of the third capacitor is connected to the second end of the fourth resistor and the output end of the optical coupling module respectively, and the second end of the third capacitor is connected to the second ground end.

9. The charging pile neutral line and live line relay detection circuit according to claim 4, characterized in that: The optical coupling module further includes: a fourth capacitor; A first end of the fourth capacitor is connected to the collector of the optocoupler and the DC power supply, and a second end of the fourth capacitor is connected to the second ground end.

10. A charging pile, characterized in that: It comprises the charging pile neutral line and live line relay detection circuit as described in any one of claims 1 to 9.

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