Charging pile power supply system

Abstract

The invention discloses a charging pile power supply system which comprises a surge suppression circuit, a first EMI filter circuit, a rectification filter circuit, a power conversion circuit and a power control circuit which are electrically connected in sequence. The power supply control circuit is used for adjusting and outputting the positive pole direct current voltage and the negative pole direct current voltage; wherein the output end of the rectification filter circuit is electrically connected with the system ground through a Y capacitor, the first EMI filter circuit comprises a first Y capacitor and a second Y capacitor which are connected in series, and a connection node between the first Y capacitor and the second Y capacitor is connected to the system ground and the ground. Electromagnetic interference and lightning protection of connection between the ground and the system ground are effectively achieved, the stability and reliability of a charging pile power supply system are remarkably improved, and real-time adjustment and high-precision output of a power source are achieved through the power source control circuit.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electromagnetic interference and lightning protection of charging pile ground, vehicle end ground and system connection, and particularly relates to a charging pile power supply system, which is suitable for electric vehicle alternating current charging pile, industrial power supply equipment and the like scenes. BACKGROUND

[0002] With the popularity of electric vehicles, the safety and stability of charging piles as key supporting facilities are crucial. Figure 1 As shown in the actual use environment, the PE (Protective Earth, protective ground) of the charging pile and the PE of the vehicle end are in the same network, and because the charging pile and the electric vehicle communicate and control through the CP (Control Pilot) signal line, and the PE of the charging pile is the reference ground of the PWM control guide CP, the PE needs to be connected to the system ground of the charging pile control board, that is, the system ground of the charging pile control board is electrically connected to the ground, so as to realize the control and communication of the CP signal. This results in that the charging pile control board and the CP signal often face various natural factor challenges, and lightning surge is one of the most destructive ones. A 6kV lightning surge can instantly generate an ultra-high voltage and a large current, which is easy to cause irreversible damage to the CP signal line and the connected electronic elements, such as breakdown of chips and burning of lines, resulting in communication interruption, charging abnormality, and even safety accidents, so the precision and stability of the +12V power supply and the -12V power supply of the CP signal line are very important.

[0003] The traditional power supply system and grounding treatment cannot comprehensively and efficiently protect the CP signal line from such high-intensity impact, and innovative protection technology is urgently needed to ensure the reliable operation of the charging pile. SUMMARY

[0004] In view of the problems in the prior art, the present application provides a charging pile power supply system.

[0005] To achieve the above-mentioned purpose, the specific scheme of the present application is as follows: A charging pile power supply system, comprising a surge suppression circuit, a first EMI filter circuit, a rectifier filter circuit, a power conversion circuit and a power control circuit connected in sequence, the power conversion circuit is used for outputting positive and negative direct current voltages, and the power control circuit is used for adjusting and outputting the positive and negative direct current voltages. The output end of the rectifier filter circuit is electrically connected to the system ground through a Y capacitor, the first EMI filter circuit comprises a first Y capacitor and a second Y capacitor connected in series, and a connection node between the first Y capacitor and the second Y capacitor is connected to the system ground and the ground.

[0006] Preferably, the power supply control circuit comprises a first power supply control circuit, a second power supply control circuit and a second EMI filter circuit, the first power supply control circuit comprises a first peak suppression circuit and a first precision adjustment circuit, the second power supply control circuit comprises a second peak suppression circuit and a second precision adjustment circuit electrically connected, and the first peak suppression circuit and the second precision adjustment circuit are electrically connected with the second EMI filter circuit.

[0007] Preferably, the first peak suppression circuit comprises resistors R3 and R4, a capacitor C2 and a diode D1, the resistors R3 and R4 are connected in parallel, one end of which is electrically connected with the capacitor C2, and the other end is electrically connected with the anode of the diode D1, and the cathode of the diode D1 is electrically connected with the other end of the capacitor C2. The first precision adjustment circuit comprises a voltage stabilizing device U4, resistors R29, R31, R32, R30, R33, R34 and a capacitor C14, the resistors R29, R31, R32, the capacitor C14 and the resistor R30 are electrically connected in sequence, the resistors R33 and R34 are connected in parallel between the resistor R30 and the capacitor C14, the anode and the reference end of the voltage stabilizing device U4 are electrically connected with the two ends of the resistor R33 respectively, and the cathode of the voltage stabilizing device U4 is connected between the resistors R31 and R32.

[0008] Preferably, the second peak suppression circuit comprises a resistor R14, a capacitor C7 and a diode D4, the cathode of the diode D4, the resistor R14 and the capacitor C7 are electrically connected in sequence, and the anode of the diode D4 is electrically connected with the other end of the resistor R14. The second precision adjustment circuit comprises a voltage stabilizing device U1 and resistors R13, R16, R17 and a capacitor EC4 electrically connected in sequence, the cathode and the reference end of the voltage stabilizing device U1 are electrically connected with the two ends of the resistor R13 respectively, and the anode of the voltage stabilizing device U1 is electrically connected with the other end of the resistor R16.

[0009] Preferably, the second EMI filter circuit comprises an electrolytic capacitor EC5, capacitors C8 and C9, and a direct current single-stage EMI filter circuit composed of an electrolytic capacitor EC3, a common-mode inductor LF1, capacitors C1 and C4, the electrolytic capacitor EC5 and the capacitor C8 are connected in parallel and electrically connected with the common-mode inductor LF1, one end of the capacitor C9 is electrically connected with the capacitor C8, and the other end is electrically connected with the common-mode inductor LF1.

[0010] Preferably, the positive output end and / or the negative output end of the power supply control circuit is connected with a fuse.

[0011] Preferably, the power conversion circuit comprises a first group of transformers and a second group of transformers, the secondary coil of the first group of transformers is electrically connected to the input end of the first power control circuit, and the secondary coil of the second group of transformers is electrically connected to the input end of the second power control circuit.

[0012] Preferably, the power conversion circuit is electrically connected to the first power control circuit through an optical coupling.

[0013] Preferably, the first EMI filter circuit comprises resistors R1 and R2, a capacitor CX1, a common-mode inductor L1, and Y capacitors CY1 and CY2, the capacitor CX1, the common-mode inductor L1, and the Y capacitors CY1 and CY2 constitute a single-stage EMI filter circuit, the resistors R1 and R2 are connected in series and then electrically connected to both ends of the capacitor CX1, one end of the CY1 is connected to a live wire, one end of the CY2 is connected to a zero line, the other ends of the CY1 and the CY2 are connected and then connected to the ground, and the connection point of the other ends of the CY1 and the CY2 and the ground is connected to one end of a magnetic bead L3, and the other end of the magnetic bead L3 is connected to a single-point ground of a system ground.

[0014] Preferably, the surge suppression circuit comprises a fuse F1, pressure-sensitive resistors RV1, RV2, and RV3, discharge tubes G1 and G2, and a thermistor RT1, one end of the pressure-sensitive resistor RV2 is connected to a live wire, the other end of the pressure-sensitive resistor RV2 is connected to one end of the discharge tube G2, the other end of the discharge tube G2 is connected to a zero line, one end of the pressure-sensitive resistor RV1 is connected to the live wire, one end of the pressure-sensitive resistor RV3 is connected to the zero line, the other ends of the pressure-sensitive resistors RV1 and RV3 are connected and then connected to one end of the discharge tube G1, the other end of the discharge tube G1 is connected to the ground, one end of the thermistor RT1 is connected to the zero line, and the other end of the thermistor RT1 is connected to the first EMI filter circuit.

[0015] The technical scheme of the present application has the following beneficial effects: In the present application, the high-voltage direct current output by the rectifier filter circuit is connected to a system ground through a Y capacitor, and the two Y capacitors of the first EMI filter circuit are connected to the system ground and the ground through a magnetic bead, effectively solving the electromagnetic interference and lightning protection of the connection between the ground and the system ground, significantly improving the stability and reliability of the charging pile power supply system, and realizing real-time adjustment and high-precision output of the power supply through the power control circuit. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The present application is a schematic diagram of an application scenario. Figure 2 The present application is a functional module block diagram. Figure 3 The present application is a circuit diagram.

[0017] Wherein, 1 - surge suppression circuit, 2 - the first EMI filter circuit, 3 - rectifier filter circuit, 4 - power conversion circuit, 5 - power control circuit, 501 - the first peak suppression circuit, 502 - the first precision adjustment circuit, 503 - the second peak suppression circuit, 504 - the second precision adjustment circuit, 505 - the second EMI filter circuit. DETAILED DESCRIPTION

[0018] The application is further described below in conjunction with the drawings and specific embodiments.

[0019] Reference Figures 2 to 3 The application provides a charging pile power supply system, comprising surge suppression circuit 1, first EMI filter circuit 2, rectifier filter circuit 3, power conversion circuit 4 and power control circuit 5 connected in sequence; the surge suppression circuit 1 is used for AC signal surge lightning suppression, the first EMI filter circuit 2 is used for suppressing electromagnetic interference to ensure that the electromagnetic compatibility (EMC) of the power supply meets the standard and avoids interfering with other electronic devices, the rectifier filter circuit 3 is used for arranging the AC signal into pulsating DC and filtering out the differential mode interference and smoothing the high frequency ripple after rectification, the power conversion circuit 4 is used for storing energy control through the transformer primary of the bus high voltage, converting into low voltage DC through the transformer secondary coil, and outputting positive DC voltage and negative DC voltage, and the power control circuit 5 is used for adjusting the positive DC voltage and the negative DC voltage and outputting.

[0020] The output end of the rectifier filter circuit 3 is connected to the system ground through a Y capacitor, the first EMI filter circuit 2 comprises a first Y capacitor and a second Y capacitor connected in series, and a connection node between the first Y capacitor and the second Y capacitor is connected to the system ground and the ground.

[0021] The power control circuit 5 comprises a first power control circuit, a second power control circuit and a second EMI filter circuit 505, the first power control circuit comprises a first peak suppression circuit 501 and a first precision adjustment circuit 502, the second power control circuit comprises a second peak suppression circuit 503 and a second precision adjustment circuit 504 connected in series, and the first peak suppression circuit 501 and the second precision adjustment circuit 505 are electrically connected to the second EMI filter circuit 505.

[0022] The power conversion circuit 4 comprises a first group of transformers and a second group of transformers, the secondary coil of the first group of transformers is electrically connected to the input end of the first power control circuit, the secondary coil of the second group of transformers is electrically connected to the input end of the second power control circuit, and the power conversion circuit is electrically connected to the first power control circuit through an optical coupling.

[0023] Embodiment one: In the embodiment, the first peak suppression circuit 501 comprises resistors R3 and R4, a capacitor C2, and a diode D1. The resistors R3 and R4 are connected in parallel, one end of which is electrically connected to the capacitor C2, and the other end of which is electrically connected to the anode of the diode D1. The cathode of the diode D1 is electrically connected to the other end of the capacitor C2. The first precision adjustment circuit 502 comprises a voltage stabilizing device U4, resistors R29, R31, R32, R30, R33, R34, and a capacitor C14. The resistors R29, R31, R32, and the capacitor C14 are connected in sequence, the resistors R33 and R34 are connected in parallel between the resistor R30 and the capacitor C14, the anode and the reference end of the voltage stabilizing device U4 are electrically connected to the two ends of the resistor R33, and the cathode of the voltage stabilizing device U4 is connected between the resistors R31 and R32.

[0024] The second peak suppression circuit 503 comprises a resistor R14, a capacitor C7, and a diode D4. The cathode of the diode D4, the resistor R14, the capacitor C7, and the anode of the diode D4 are connected in sequence. The second precision adjustment circuit 504 comprises a voltage stabilizing device U1 and resistors R13, R16, R17, and a capacitor EC4 connected in sequence. The cathode and the reference end of the voltage stabilizing device U1 are electrically connected to the two ends of the resistor R13, and the anode of the voltage stabilizing device U1 is electrically connected to the other end of the resistor R16.

[0025] The second EMI filter circuit 505 comprises an electrolytic capacitor EC5, capacitors C8 and C9, and a direct current single-stage EMI filter circuit composed of an electrolytic capacitor EC3, a common-mode inductor LF1, capacitors C1 and C4. The electrolytic capacitor EC5 and the capacitor C8 are connected in parallel and electrically connected to the common-mode inductor LF1. One end of the capacitor C9 is electrically connected to the capacitor C8, and the other end of the capacitor C9 is electrically connected to the common-mode inductor LF1.

[0026] The positive output end and / or the negative output end of the power supply control circuit 5 is connected with a fuse.

[0027] In the embodiment, the first group of transformer secondary coils in the power conversion circuit 4 outputs +14V direct current voltage, and the second group of transformer secondary coils outputs -14V direct current voltage. These two groups of direct current voltages are adjusted by the first power supply control circuit and the second power supply control circuit to high-precision and interference-free ±12V direct current power supply, and then the electromagnetic interference of the +12V and -12V two-way power supply is filtered out by the second EMI filter circuit, and the energy is smoothed and stored to supply power to the CP signal circuit for communication between the charging pile and the vehicle end.

[0028] Embodiment two: In the embodiment, the first EMI filter circuit comprises resistors R1 and R2, a capacitor CX1, a common mode inductor L1, and Y capacitors CY1 and CY2, the capacitor CX1, the common mode inductor L1, and the Y capacitors CY1 and CY2 form a single-stage EMI filter circuit, the resistors R1 and R2 are connected in series and electrically connected to both ends of the capacitor CX1, one end of the CY1 is connected to a live wire, one end of the CY2 is connected to a neutral wire, the other ends of the CY1 and CY2 are connected and then connected to the ground, the connection point of the other ends of the CY1 and CY2 and the ground is connected to one end of a magnetic bead L3, the other end of the magnetic bead L3 is connected to a single-point ground of a system ground. The single-point ground is directly connected to a system ground plane, and the single-point ground is reinforcedly insulated from the live wire and the neutral wire, thereby solving the electromagnetic interference of a power grid on the system ground, lightning protection, and reliable reference of a CP communication signal.

[0029] Embodiment three In the embodiment, the surge suppression circuit comprises a fuse F1, voltage-dependent resistors RV1, RV2, and RV3, discharge tubes G1 and G2, and a thermistor RT1, one end of the voltage-dependent resistor RV2 is connected to a live wire, the other end of the voltage-dependent resistor RV2 is connected to one end of the discharge tube G2, the other end of the discharge tube G2 is connected to a neutral wire, one end of the voltage-dependent resistor RV1 is connected to the live wire, one end of the voltage-dependent resistor RV3 is connected to the neutral wire, the other ends of the voltage-dependent resistors RV1 and RV3 are connected and then connected to one end of the discharge tube G1, the other end of the discharge tube G1 is connected to the ground, one end of the thermistor RT1 is connected to the neutral wire, and the other end of the thermistor RT1 is connected to the first EMI filter circuit.

[0030] In the embodiment, since the failure mode of the voltage-dependent resistor is short circuit, when the voltage-dependent resistor RV2 fails due to a lightning surge impact, the discharge tube G2 is automatically disconnected to prevent the live wire and the neutral wire from being short-circuited, and when the voltage-dependent resistors RV1 and RV3 fail due to a lightning surge impact, the discharge tube G1 is automatically disconnected to prevent the live wire and the neutral wire from being short-circuited to the ground and the live wire and the neutral wire from being short-circuited.

[0031] The above only describes the preferred embodiments of the present application, and does not limit the patent scope of the present application, and any equivalent structural transformation made according to the content of the present application specification and drawings, or direct / indirect application in other related technical fields is included in the protection scope of the present application.

Claims

1. A charging pile power supply system, characterized in that, The device includes a surge suppression circuit, a first EMI filter circuit, a rectifier filter circuit, a power conversion circuit, and a power control circuit that are connected in sequence. The power conversion circuit is used to output a positive DC voltage and a negative DC voltage, and the power control circuit is used to adjust and output the positive DC voltage and the negative DC voltage. The output of the rectifier filter circuit is electrically connected to the system ground via a Y capacitor. The first EMI filter circuit includes a first Y capacitor and a second Y capacitor connected in series. The connection node between the first Y capacitor and the second Y capacitor is connected to the system ground and earth ground.

2. The charging post power supply system of claim 1, wherein, The power control circuit includes a first power control circuit, a second power control circuit, and a second EMI filter circuit. The first power control circuit includes a first peak suppression circuit and a first precision adjustment circuit. The second power control circuit includes a second peak suppression circuit and a second precision adjustment circuit that are electrically connected. Both the first peak suppression circuit and the second precision adjustment circuit are electrically connected to the second EMI filter circuit.

3. The charging station power supply system of claim 2, wherein, The first peak suppression circuit includes resistors R3 and R4, capacitor C2, and diode D1. After resistors R3 and R4 are connected in parallel, one end is electrically connected to capacitor C2, and the other end is electrically connected to the positive terminal of diode D1. The negative terminal of diode D1 is electrically connected to the other end of capacitor C2. The first precision adjustment circuit includes a voltage regulator U4, resistors R29, R31, R32, R30, R33, R34, and capacitor C14. Resistors R29, R31, R32, capacitor C14, and resistor R30 are connected in sequence. Resistors R33 and R34 are connected in parallel between resistor R30 and capacitor C14. The anode and reference terminal of the voltage regulator U4 are electrically connected to the two ends of resistor R33, respectively. The cathode of the voltage regulator U4 is connected between resistors R31 and R32.

4. The charging pile power supply system according to claim 2, characterized in that, The second peak suppression circuit includes a resistor R14, a capacitor C7, and a diode D4, wherein the cathode of the diode D4, the resistor R14, the capacitor C7, and the anode of the diode D4 are connected in sequence. The second precision adjustment circuit includes a voltage regulator U1 and resistors R13, R16, R17 and capacitor EC4 connected in sequence. The cathode and reference terminal of the voltage regulator U1 are electrically connected to both ends of resistor R13, and the anode of the voltage regulator U1 is electrically connected to the other end of resistor R16.

5. The charging pile power supply system according to claim 2, characterized in that, The second EMI filter circuit includes electrolytic capacitor EC5, capacitor C8, C9 and a DC single-stage EMI filter circuit composed of electrolytic capacitor EC3, common-mode inductor LF1, capacitor C1, C4. Electrolytic capacitor EC5 and capacitor C8 are connected in parallel and then electrically connected to common-mode inductor LF1. One end of capacitor C9 is electrically connected to capacitor C8 and the other end is electrically connected to common-mode inductor LF1.

6. The charging pile power supply system according to claim 2, characterized in that, A fuse is connected to the positive and / or negative output terminals of the power control circuit.

7. The charging pile power supply system according to claim 2, characterized in that, The power conversion circuit includes a first set of transformers and a second set of transformers. The secondary coil of the first set of transformers is electrically connected to the input terminal of the first power control circuit, and the secondary coil of the second set of transformers is electrically connected to the input terminal of the second power control circuit.

8. The charging pile power supply system according to claim 7, characterized in that, The power conversion circuit is electrically connected to the first power control circuit via an optocoupler.

9. The charging pile power supply system according to any one of claims 1-8, characterized in that, The first EMI filter circuit includes resistors R1 and R2, capacitor CX1, common-mode inductor L1, and Y capacitors CY1 and CY2. The capacitors CX1, common-mode inductor L1, and Y capacitors CY1 and CY2 form a single-stage EMI filter circuit. Resistors R1 and R2 are connected in series and electrically connected to both ends of capacitor CX1. One end of CY1 is connected to the live wire, and one end of CY2 is connected to the neutral wire. The other ends of CY1 and CY2 are connected to the ground. The connection point between the other ends of CY1 and CY2 and the ground is connected to one end of ferrite bead L3. The other end of ferrite bead L3 is grounded to the system ground at a single point.

10. The charging pile power supply system according to claim 9, characterized in that, The surge suppression circuit includes a fuse F1, varistors RV1, RV2, and RV3, discharge tubes G1 and G2, and a thermistor RT1. One end of the varistor RV2 is connected to the live wire, and the other end is connected to one end of the discharge tube G2, the other end of which is connected to the neutral wire. One end of the varistor RV1 is connected to the live wire, and one end of the varistor RV3 is connected to the neutral wire. The other ends of the varistor RV1 and RV3 are connected to one end of the discharge tube G1, the other end of which is connected to the ground. One end of the thermistor RT1 is connected to the neutral wire, and the other end is connected to the first EMI filter circuit.

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