Relay control method for charging pile

Abstract

The invention relates to the field of charging pile relay control, in particular to a relay control method for a charging pile. An output signal of the chip U1 and a control signal sent by a controller are operated through an OR gate circuit composed of diodes, as long as one of the two signals is high, a control signal of a third intermediate relay K10 is in a high level, the third intermediate relay K10 acts, a relay for controlling power scheduling cannot be closed, and power scheduling cannot be carried out; only when the two input signals of the chip U1 are both low, the output is low level, and the relay for dispatching the power can be closed, that is, only when one trolley is charged and the dispatching power is required, the relay for dispatching the power is allowed to be closed. Therefore, the accuracy and the reliability of the action of the relay are ensured from two aspects of signal control and relay connection.

Description

Technical Field

[0001] The present invention relates to the field of relay control of a charging pile, and in particular to a relay control method for a charging pile. Background Art

[0002] In the application scenarios of civilian charging piles, DC charging piles are widely used. In order to reasonably and fully utilize the charging power, the integrated DC piles in the community are usually equipped with double guns. When one car is charging, all the power is allocated to this car. When two cars are charging, the charging power is allocated on demand or in proportion. There are separate relays in the two charging guns to control the output of each charging gun, and there is a set of relays between the two charging guns to control the power scheduling between the two charging guns. Usually, each charging gun is equipped with a set of charging modules to provide charging power. Various manufacturers tend to use transistors directly to enhance the relay drive signal sent by the controller, and then directly control the relay. This design is normal. There is no problem, but power electronic equipment usually produces greater interference. When the interference is large or the power supply fluctuates, the relay may malfunction, causing equipment failure or damage.

[0003] Manufacturers tend to use transistors to directly enhance the relay drive signal sent by the controller, and then directly control the relay. This design is fine under normal circumstances, but power electronic equipment usually produces greater interference. When the interference is large or the power supply fluctuates, the relay may malfunction, causing equipment failure or damage. Summary of the invention

[0004] In order to solve the problems of the prior art, the present invention provides a relay control method for a charging pile. This patent is used for charging piles and can solve the reliability problem of relay control logic; while ensuring the normal operation of the relay, an interlocking circuit is invented to ensure the reliability of the control logic.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A relay control method for a charging pile, characterized in that it comprises the following steps: S1: The driving signal generated by the controller controls the intermediate relays K6, K9 and K10, and then controls the output relay. DC1-EN is the control signal of the first charging gun output relay issued by the controller. This signal is valid at a low level. When this signal is at a high level, pins 5 and 7 of the intermediate relay K6 are connected, and pins 6 and 8 are connected. Pins 7 and 8 of the intermediate relay K6 are the control signals of the positive and negative bus relays of the first charging gun, respectively. At this time, they are both grounded and at a low level. At this time, the output relay is disconnected. On the contrary, when this signal is at a low level, pins 7 and 8 of the intermediate relay K6 are both at a high level, and the output relay is energized. S2: One end of the control terminal of the intermediate relay K10 is connected to the control signal, and the other end is connected to the pins 3 and 4 of the intermediate relay K6 and the intermediate relay K9. When one of the intermediate relays K6 and K9 is activated, one end of the control terminal of the intermediate relay K10 is grounded, and the other end is connected to the control signal, and the control can be accepted normally. S3: When the intermediate relay K6 and the intermediate relay K9 are both in action, one end of the control terminal is connected to the control signal, and the other end is left hanging. At this time, the charging power cannot be scheduled; the control signals of the intermediate relay K6 and the intermediate relay K9 are directly generated by the controller, and the control signal of the intermediate relay K10 is firstly XOR-NORed by the control signals of the intermediate relay K6 and the intermediate relay K9. When the states of the intermediate relay K6 and the intermediate relay K9 are the same, the chip U1 outputs a high level, and when the states are different, it outputs a low level; S4: The output signal of chip U1 and the control signal from the controller are operated through the OR gate circuit. As long as one of the two signals is high, the control signal of intermediate relay three K10 will be high level, and intermediate relay three K10 will act. Only when both input signals of chip U1 are low, the output will be low level, and the power dispatching relay can be energized.

[0006] Compared with the prior art, the invention has the following beneficial effects: an interlocking circuit is designed under the premise of ensuring the charging logic, which ensures the normal operation of the relay control circuit while avoiding possible malfunctions under special circumstances, thereby improving the reliability of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Other features, objectives and advantages of the present invention will become more apparent from a reading of the detailed description of non-limiting embodiments made with reference to the following accompanying drawings.

[0008] Figure 1 It is a circuit schematic diagram of the present invention.

[0009] Figure 2 It is the circuit principle diagram of the chip U1 of the present invention. DETAILED DESCRIPTION

[0010] The present invention is further described in detail below by examples. The examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0011] A relay control method for a charging pile comprises: an intermediate relay circuit 1, an intermediate relay circuit 2 and an intermediate relay circuit 3, wherein the intermediate relay circuit 1 is connected to the intermediate relay circuit 2, and the intermediate relay circuit 2 is connected to the intermediate relay circuit 3; the intermediate relay circuit 1, the intermediate relay circuit 2 and the intermediate relay circuit 3 constitute an intermediate relay circuit, the intermediate relay circuit is connected to an output relay, a driving signal generated by a controller controls the intermediate relay circuit, and controls the output relay through the intermediate relay circuit.

[0012] The intermediate relay circuit 1 includes: The intermediate relay K6 has its pin 2 grounded, the pin 1 of the intermediate relay K6 is connected to one end of the resistor R4, the resistor R4 is a current limiting resistor, the pins 1 and 2 are the coil connection pins of the intermediate relay K6, the other end of the resistor R4 is connected to the controller, one end of the resistor R4 is connected to the anode of the diode LED6, the cathode of the diode LED6 is grounded, the intermediate relay K6 is connected to the cathode of the diode D4, and the anode of the diode D4 is grounded; the diode D4 is a freewheeling diode, which plays a freewheeling role and serves as a freewheeling path when the coil of the intermediate relay K6 is disconnected. The drive signal DC1-EN generated by the controller acts on the intermediate relay K6 through the resistor R4; DC1-EN is the first charging gun output relay control signal generated by the controller chip, and the low level is valid; Pin 6 and pin 5 of intermediate relay K6 are grounded, pin 3 and pin 4 of intermediate relay K6 are connected to intermediate relay circuit 2, pin 3 and pin 4 are normally closed contacts, pin 8 of intermediate relay K6 is connected to resistor R8, output terminal 1 is set between pin 8 of intermediate relay K6 and resistor R8, the output terminal 1 outputs DC1-OUT-, DC1-OUT- is the negative bus relay control signal of the output end of the first charging gun, high level is valid, one end of resistor R8 is connected to the power supply, and the power supply voltage is 12V; preferably, a diode LED4 is set between resistor R8 and pin 8, the anode of diode LED4 is connected to one end of R8, the cathode of diode LED4 is connected to output terminal 1, the output terminal 1 is connected to the anode of diode D5, and the cathode of diode D5 is connected to the power supply; diode D5 is a freewheeling diode, which plays a freewheeling role and serves as a freewheeling path when the output relay coil is disconnected. Pin 7 of the intermediate relay K6 is connected to the resistor R9, and pins 7 and 8 are normally open contacts. An output terminal 2 is set between pin 7 of the intermediate relay K6 and the resistor R9, and the output terminal 2 outputs DC1-OUT+, DC1-OUT+ is the positive bus relay control signal of the first charging gun output terminal, and the high level is valid. One end of the resistor R9 is connected to the power supply, and the power supply voltage is 12V; preferably, a diode LED5 is set between the resistor R9 and pin 7, the anode of the diode LED5 is connected to one end of R9, the cathode of the diode LED5 is connected to the output terminal 2, the output terminal 2 is connected to the anode of the diode D6, and the cathode of the diode D6 is connected to the power supply; the diode D6 is a freewheeling diode, which plays a freewheeling role and serves as a freewheeling path when the output relay coil is disconnected; The structure of the intermediate relay circuit 2 is consistent with that of the intermediate relay circuit 1. The intermediate relay circuit 2 includes the intermediate relay 2 K9, whose pins 3 and 4 are normally closed contacts. The pins 3 and 4 of the intermediate relay 1 K6 are connected to the pins 3 and 4 of the intermediate relay 2 K9; the intermediate relay circuit 2 outputs DC2-OUT- between the pin 8 of the intermediate relay 2 K9 and the resistor R12. DC2-OUT- is the negative bus relay control signal of the output end of the second charging gun, and the high level is valid; the driving signal DC2-EN generated by the controller acts on the intermediate relay 2 K9 through the resistor R11; The intermediate relay circuit 2 outputs DC2-OUT+ between the pin 7 of the intermediate relay 2 K9 and the resistor R13; DC2-OUT+ is the positive bus relay control signal of the second charging gun output end, and the high level is valid; The intermediate relay circuit three includes an intermediate relay three K10, and the intermediate relay three K10 has the same structure as the intermediate relay two K9, wherein the intermediate relay three K10 is connected to the OR gate circuit through a resistor R26, and the OR gate circuit is connected to the chip U1 and the controller, and the OR gate circuit includes a diode D1 and a diode D2, the cathode of the diode D1 is connected to one end of the resistor R19, the anode of the diode D1 is connected to the pin 4 of the chip U1, the pin 3 of the chip U1 is grounded, the pin 2 of the chip U1 is connected to the controller, the controller transmits the DC2-EN signal to the chip U1 through the pin 2, the pin 1 of the chip is connected to the controller, the controller transmits the DC1-EN signal to the chip U1 through the pin 1, and the pin 5 of the chip U1 is connected to the power supply, and the power supply voltage is 12V; the other end of the resistor R19 is connected to one end of the resistor R20, the other end of the resistor R20 is connected to the cathode of the diode D2, and the anode of the diode D2 is connected to the controller; One end of the resistor R26 is connected to the pin 1 of the intermediate relay K10, and the pin 2 of the intermediate relay K10 is connected to the pins 3 and 4 of the intermediate relay K9; DC2-EN is the second charging gun output relay control signal generated by the controller chip, and the low level is valid; PAREN-C is the control signal of the power dispatching relay generated by the controller chip, and the low level is valid; PAR-EN is the control signal of the power dispatching relay generated by the logic operation of the chip U1, and the low level is valid; PAR-EN acts on the intermediate relay K10 through the resistor R26; One end of the resistor R26 is connected to the anode of the diode LED30, and at the same time, one end of the resistor R26 is connected to the cathode of the diode D15, the anode of the diode D15 is connected to the cathode of the diode LED30, and the cathode of the diode D15 and the anode of the diode LED30 are both connected to pin 1 of the intermediate relay three K10; the anode of the diode D15 and the cathode of the diode LED30 are connected to pin 2 of the intermediate relay three K10 through a wire; pins 1 and 2 are coil connection pins, pins 5 and 6 of the intermediate relay three K10 are grounded, pins 4 and 3 of the intermediate relay three K10 are normally closed, pins 7 and 8 are normally open, and DC-P-OUT- is output between pin 8 of the intermediate relay three K10 and the resistor R29, DC-P-OUT- is the negative bus relay control signal of the power scheduling loop, and the high level is valid, and DC-P-OUT+ is output between pin 7 of the intermediate relay three K10 and the resistor R30; DC-P-OUT+ is the positive bus relay control signal of the power scheduling loop, and the high level is valid; Relays are provided on the positive and negative busbars of charging guns 1 and 2. Since the driving signal generated by the controller has a weak driving capability, it cannot directly drive the relay.

[0013] This solution includes the following steps: the driving signal generated by the controller controls the intermediate relays intermediate relay 1 K6, intermediate relay 2 K9 and intermediate relay 3 K10, and then controls the output relay. DC1-EN is the control signal of the first charging gun output relay issued by the controller, and this signal is valid at a low level. When this signal is at a high level, pins 5 and 7 of the intermediate relay 1 K6 are connected, and pins 6 and 8 are connected. Pins 7 and 8 of the intermediate relay 1 K6 are respectively the control signals of the positive and negative bus relays of the first charging gun. At this time, they are all grounded and at a low level, and the output relay cannot be driven. At this time, the output relay is disconnected; on the contrary, when this signal is at a low level, the intermediate relay cannot be energized, and pins 7 and 8 of the intermediate relay 1 K6 are both at a high level, and the output relay is energized.

[0014] Similarly, the working principle of the second charging gun relay control circuit is the same as that of the first charging gun. When one car is charging, the output relay of the corresponding charging gun is energized, and the charging power matched by the second charging gun is also allowed to be dispatched to the first charging gun; when two cars are charging at the same time, power dispatch is not allowed. If power dispatch is required, the charging power of one car needs to be stopped. Therefore, when two cars are charging at the same time, the relay for dispatching power is prohibited from being energized, while when one car is charging, the relay for dispatching power is allowed to be energized.

[0015] One end of the control end of the intermediate relay K10 is connected to the control signal, and the other end is connected to pins 3 and 4 of the intermediate relay K6 and the intermediate relay K9. When one of the intermediate relays K6 and K9 is activated, one end of the control end of the intermediate relay K10 is grounded, and the other end is connected to the control signal, so it can be controlled normally.

[0016] When both the intermediate relay K6 and the intermediate relay K9 are in action, one end of the control terminal receives the control signal, and the other end is suspended. The intermediate relay K10 cannot receive the control signal and cannot be attracted. At this time, the charging power cannot be dispatched. The control signals of the intermediate relay K6 and the intermediate relay K9 are directly generated by the controller, and the control signal of the intermediate relay K10 is firstly XOR-NORed by the control signals of the intermediate relay K6 and the intermediate relay K9, that is, Y=(A⊕B)! , the chip U1 is the XOR-NOR gate operation chip. When the intermediate relay K6 and the intermediate relay K9 are in the same state, the chip U1 outputs a high level, and when the state is different, it outputs a low level.

[0017] The output signal of chip U1 and the control signal from the controller are operated through an OR gate circuit composed of diodes. As long as one of the two signals is high, the control signal of intermediate relay 3 K10 will be high level, and intermediate relay 3 K10 will act, but the relay controlling power dispatching cannot be energized, and power dispatching cannot be performed; only when both input signals of chip U1 are low, the output will be low level, and the relay for dispatching power can be energized, that is, only when one car is charging and there is a demand for dispatching power, the relay for dispatching power is allowed to be energized. In this way, the accuracy and reliability of relay action are guaranteed from the aspects of signal control and relay connection.

Claims

1. A relay control method for a charging pile, characterized in that: The steps include: S1: The driving signal generated by the controller controls the intermediate relays K6, K9 and K10, and then controls the output relays; DC1-EN is the control signal of the first charging gun output relay sent by the controller. This signal is valid at a low level. When this signal is at a high level, pins 5 and 7 of the intermediate relay K6 are connected, and pins 6 and 8 are connected. Pins 7 and 8 of the intermediate relay K6 are the control signals of the positive and negative bus relays of the first charging gun, respectively. At this time, both are grounded and at a low level. At this time, the output relay is disconnected. On the contrary, when this signal is at a low level, pins 7 and 8 of the intermediate relay K6 are both at a high level, and the output relay is energized. S2: One end of the control terminal of the intermediate relay K10 is connected to the control signal, and the other end is connected to the pins 3 and 4 of the intermediate relay K6 and the intermediate relay K9. When one of the intermediate relays K6 and K9 is activated, one end of the control terminal of the intermediate relay K10 is grounded, and the other end is connected to the control signal, and the control can be accepted normally. S3: When the intermediate relay K6 and the intermediate relay K9 are both in action, one end of the control terminal is connected to the control signal, and the other end is left hanging. At this time, the charging power cannot be scheduled; the control signals of the intermediate relay K6 and the intermediate relay K9 are directly generated by the controller, and the control signal of the intermediate relay K10 is firstly XOR-NORed by the control signals of the intermediate relay K6 and the intermediate relay K9. When the states of the intermediate relay K6 and the intermediate relay K9 are the same, the chip U1 outputs a high level, and when the states are different, it outputs a low level; S4: The output signal of chip U1 and the control signal from the controller are operated through the OR gate circuit. As long as one of the two signals is high, the control signal of intermediate relay three K10 will be high level, and intermediate relay three K10 will act. Only when both input signals of chip U1 are low, the output will be low level, and the power dispatching relay can be energized.

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