Charging pile BMS power supply control circuit, direct current charging pile and charging system

Abstract

The application relates to a charging pile BMS power supply control circuit, a direct-current charging pile and a charging system. The charging pile BMS power supply control circuit comprises a first power supply, a second power supply, a first relay and a second relay. The input end of each relay is connected to the voltage output end of the corresponding power supply. First and second diodes in series are additionally arranged in front of and behind the relay, and a third relay is arranged at the two ends of the first and second diodes and connected to the output ends of the first and second relays. A third resistor is arranged between the second diode and the BMS power supply output end of the direct-current charging pile. The two ends of the third resistor are connected to current sampling points for collecting the instantaneous value of the power supply loop current through resistors. The charging control unit can stop charging the vehicle when the CAN communication between the charging control unit and the BMS of the vehicle to be charged is abnormal, so that the direct-current charging pile is prevented from misjudging the power supply due to the vehicle BMS fault.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of charging piles, in particular to a charging pile BMS power supply control circuit, a direct current charging pile and a charging system. BACKGROUND

[0002] The direct current charging pile is a common charging pile equipment. When the existing direct current charging pile performs automatic charging work on a vehicle to be charged, the charging control unit of the direct current charging pile first enables the 12V power supply output voltage to the battery management system (BMS) of the vehicle to be charged. Once the battery management system of the vehicle and the charging control unit of the direct current charging pile communicate through CAN, the direct current charging pile selects the 12V power supply to perform charging operation on the vehicle to be charged. If the battery management system of the vehicle and the charging control unit of the direct current charging pile do not communicate through CAN, the charging control unit of the direct current charging pile switches the current 12V power supply to 24V power supply to perform charging operation on the vehicle to be charged. The existing direct current charging pile BMS power supply control circuit is shown in Figure 1

[0003] However, the existing direct current charging pile BMS power supply control circuit has the following disadvantages: when the battery management system of the vehicle itself fails, the battery management system of the vehicle and the charging control unit of the direct current charging pile cannot normally communicate through CAN, resulting in that the charging control unit of the direct current charging pile judges that there is no CAN communication between it and the battery management system of the vehicle, and then the charging control unit of the direct current charging pile directly provides 24V power supply to the vehicle to be charged for charging, which will damage the battery management system of the vehicle. SUMMARY

[0004] The first technical problem to be solved by the present application is to provide a charging pile BMS power supply control circuit that avoids misjudgment of power supply of a direct current charging pile due to vehicle BMS failure.

[0005] The second technical problem to be solved by the present application is to provide a direct current charging pile applying the above-mentioned direct current charging pile BMS power supply control circuit.

[0006] The third technical problem to be solved by the present application is to provide a charging system applying the above-mentioned direct current charging pile.

[0007] The technical solution adopted by the present application to solve the first technical problem is: a charging pile BMS power supply control circuit, comprising:

[0008] a first power supply having a voltage output end outputting a first power supply voltage;

[0009] ​The second power supply has a voltage output end outputting a second power voltage; wherein the voltage value of the second power voltage is greater than the voltage value of the first power voltage.

[0010] The first relay has an input end connected to the voltage output end of the first power supply.

[0011] The second relay has an input end connected to the voltage output end of the second power supply.

[0012] characterized in that it further comprises:

[0013] The first diode has a positive electrode connected to the output end of the first relay.

[0014] The second diode has a positive electrode connected to the negative electrode of the first diode, and a negative electrode connected to the output end of the second relay.

[0015] The third relay has an input end connected to the output end of the first relay, and an output end connected to the negative electrode of the second diode.

[0016] The first capacitor has a first end connected to the negative electrode of the second diode through the first resistor, and a second end connected to a ground end.

[0017] The second capacitor has a first end connected to the BMS power output end of the charging pile through the second resistor, and a second end connected to the ground end; wherein a third resistor is arranged between the negative electrode of the second diode and the BMS power output end of the charging pile.

[0018] The charging control unit is connected to a first current sampling point on the line between the first capacitor and the first resistor, and a second current sampling point on the line between the second capacitor and the second resistor; and the charging control unit is connected to the first relay, the second relay and the third relay to control the switching actions of the relays.

[0019] In the improved charging pile BMS power control circuit, the third resistor is a manganese-copper resistor.

[0020] In the further improved charging pile BMS power control circuit, the first power voltage is 12V, and the second power voltage is 24V.

[0021] In the further improved charging pile BMS power control circuit, the resistance value of the first resistor and the resistance value of the second resistor are both 1000Ω; and the capacitance value of the first capacitor and the capacitance value of the second capacitor are both 100nF.

[0022] In the further improved charging pile BMS power control circuit, the resistance value of the third resistor is 0.2Ω.

[0023] Preferably, in the charging pile BMS power supply control circuit, the first diode and the second diode are both EM520 type diodes.

[0024] The direct current charging pile of the present application solves the second technical problem by using the charging pile BMS power supply control circuit.

[0025] The charging system of the present application solves the third technical problem by using the direct current charging pile.

[0026] Preferably, in the charging system, the server is in wireless communication connection with the direct current charging pile.

[0027] Preferably, in the charging system, the server is in wireless communication connection with the direct current charging pile.

[0028] Compared with the prior art, the charging pile BMS power supply control circuit of the present application has the following advantages: by adding the first diode and the second diode in series before and after the existing BMS power supply control circuit, and the third relay corresponding to the connection of the first relay output end and the second relay output end at both ends, and by setting the third resistor between the second diode and the BMS power supply output end of the direct current charging pile, the third resistor has a current sampling point for collecting the instantaneous value of the power supply loop current at both ends through the resistor, so that the charging control unit can stop charging the vehicle when the CAN communication between the charging control unit and the BMS of the vehicle to be charged is abnormal, thereby avoiding the misjudgment of the power supply of the direct current charging pile due to the fault of the vehicle BMS. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 The existing charging pile BMS power supply control circuit is shown in the figure;

[0030] Figure 2 The charging pile BMS power supply control circuit in the embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0031] The present application will be further described in detail below with reference to the embodiments of the drawings.

[0032] The present embodiment provides a charging pile BMS power supply control circuit, which is specifically applicable to a direct current charging pile. Specifically, referring to Figure 2 The charging pile BMS power supply control circuit in the embodiment includes:

[0033] a first power supply VCC having a voltage output end outputting a first power supply voltage;

[0034] The second power supply VDD has a voltage output terminal for outputting the second power supply voltage; wherein the voltage value of the second power supply voltage is greater than the voltage value of the first power supply voltage.

[0035] The first relay K1 has its input terminal connected to the voltage output terminal of the first power supply VCC;

[0036] The second relay K2 has its input terminal connected to the voltage output terminal of the second power supply VDD;

[0037] The positive terminal of the first diode D1 is connected to the output terminal of the first relay K1;

[0038] The positive terminal of the second diode D2 is connected to the negative terminal of the first diode D1, and the negative terminal of the second diode D2 is connected to the output terminal of the second relay K2.

[0039] The input terminal of the third relay K3 is connected to the output terminal of the first relay K1, and the output terminal of the third relay K3 is connected to the negative terminal of the second diode D2.

[0040] The first capacitor C1 has its first terminal connected to the negative terminal of the second diode D2 through the first resistor R1, and its second terminal connected to the ground terminal GND.

[0041] The second capacitor C2 has its first end connected to the BMS power supply output terminal V_BMS of the DC charging pile through the second resistor R2, and its second end connected to the ground terminal GND; wherein, a third resistor R3 is provided between the negative terminal of the second diode D2 and the BMS power supply output terminal V_BMS of the DC charging pile.

[0042] The charging control unit M is connected to the first current sampling point ADC1 located on the line connecting the first capacitor C1 and the first resistor R1, and the second current sampling point ADC2 located on the line connecting the second capacitor C2 and the second resistor R2; and the charging control unit M is connected to the first relay K1, the second relay K2 and the third relay K3 to control the switching action of each relay.

[0043] In this specific embodiment, the third resistor R3 is a manganese copper resistor with a resistance of 0.2Ω. The first supply voltage is 12V, and the second supply voltage is 24V. The resistances of the first resistor R1 and the second resistor R2 are both 1000Ω; the capacitances of the first capacitor C1 and the second capacitor C2 are both 100nF; and both the first diode D1 and the second diode D2 are EM520 type diodes.

[0044] The following combination Figure 2The power supply control principle of the charging pile BMS power supply control circuit in this embodiment is explained:

[0045] When the user inserts the charging gun of the DC charging pile into the charging input terminal of the vehicle to be charged, the charging control unit M of the charging pile first controls the closing of the first relay K1. Here, the first diode D1 and the second diode D2 provide a voltage drop of about 3.2V, and the battery management system of the vehicle to be charged receives a voltage of about 8.8V, avoiding the BMS operating range of 24V voltage provided by the second power supply VDD, thus avoiding misjudgment by the charging control unit.

[0046] The charging control unit M obtains the instantaneous current value of the power supply circuit through the first current sampling point ADC1 and the second current sampling point ADC2 to determine whether the battery management system of the vehicle to be charged has started working:

[0047] The charging control unit M interacts with the BMS of the vehicle to be charged via CAN communication to further determine whether the BMS of the vehicle to be charged is operational.

[0048] Case 1: If the instantaneous current value collected by the current sampling point reaches the preset current threshold and the CAN communication is normal, then the third relay K3 is closed to provide 12V power to the BMS of the charging vehicle.

[0049] Scenario 2: If the instantaneous current value collected by the current sampling point reaches the preset current threshold, but the CAN communication between the charging control unit M and the BMS of the vehicle to be charged is abnormal, the charging pile determines that the CAN communication is abnormal and stops the charging process.

[0050] Scenario 3: If the instantaneous current value collected by the current sampling point does not reach the preset current threshold, and the CAN communication between the charging control unit M and the BMS of the vehicle to be charged is abnormal, then the first relay K1 is disconnected and the second relay K2 is closed, thereby providing 24V power to the BMS of the vehicle to be charged. If the CAN communication between the charging control unit M and the BMS of the vehicle to be charged is normal after closing the second relay K2, then the charging process will proceed; otherwise, the charging pile determines that the CAN communication is abnormal and stops the charging process.

[0051] The charging pile BMS power supply control circuit of this embodiment adds a first diode and a second diode connected in series to the existing charging pile BMS power supply control circuit, and a third relay with its two ends respectively connected to the output terminals of the first relay and the second relay. A third resistor is set between the second diode and the BMS power supply output terminal V_BMS of the DC charging pile, and the two ends of the third resistor are respectively set with current sampling points for collecting the instantaneous value of the power supply circuit current. In this way, the charging control unit can stop charging the vehicle when the CAN communication between the charging control unit and the BMS of the vehicle to be charged is abnormal, based on the judgment of the instantaneous value of the power supply circuit current after the first relay is closed and the closing processing of each relay, thereby avoiding the DC charging pile misjudging the power supply due to the vehicle BMS failure.

[0052] This embodiment also provides a DC charging pile. The DC charging pile utilizes the aforementioned charging pile BMS power supply control circuit.

[0053] This embodiment also provides a charging system including a server. The charging system utilizes the aforementioned DC charging pile, and the server and the DC charging pile are connected wirelessly.

[0054] Although preferred embodiments of the present invention have been described in detail above, it should be clearly understood that various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. Charging pile BMS power supply control circuit, including: The first power supply (VCC) has a voltage output terminal that outputs the first power supply voltage; The second power supply (VDD) has a voltage output terminal for outputting a second power supply voltage; wherein the voltage value of the second power supply voltage is greater than the voltage value of the first power supply voltage. The first relay (K1) has its input terminal connected to the voltage output terminal of the first power supply (VCC); The second relay (K2) has its input terminal connected to the voltage output terminal of the second power supply (VDD); Its characteristic is that it further includes: The positive terminal of the first diode (D1) is connected to the output terminal of the first relay (K1); The positive terminal of the second diode (D2) is connected to the negative terminal of the first diode (D1), and the negative terminal of the second diode (D2) is connected to the output terminal of the second relay (K2). The third relay (K3) has its input terminal connected to the output terminal of the first relay (K1), and its output terminal is connected to the negative terminal of the second diode (D2). The first capacitor (C1) has its first terminal connected to the negative terminal of the second diode (D2) through the first resistor (R1), and its second terminal connected to the ground terminal (GND). The second capacitor (C2) has its first end connected to the BMS power supply output terminal (V_BMS) of the charging pile through the second resistor (R2), and its second end connected to the ground terminal (GND); a third resistor (R3) is provided between the negative terminal of the second diode (D2) and the BMS power supply output terminal (V_BMS) of the charging pile. The charging control unit (M) is connected to a first current sampling point (ADC1) on the line connecting the first capacitor (C1) and the first resistor (R1) and a second current sampling point (ADC2) on the line connecting the second capacitor (C2) and the second resistor (R2); and the charging control unit (M) is connected to a first relay (K1), a second relay (K2) and a third relay (K3) to control the switching action of each relay.

2. The charging pile BMS power supply control circuit according to claim 1, characterized in that, The third resistor (R3) is a manganese copper resistor.

3. The charging pile BMS power supply control circuit according to claim 1, characterized in that, The first power supply voltage is 12V, and the second power supply voltage is 24V.

4. The charging pile BMS power supply control circuit according to claim 3, characterized in that, The resistance of the first resistor (R1) and the resistance of the second resistor (R2) are both 1000Ω; the capacitance of the first capacitor (C1) and the capacitance of the second capacitor (C2) are both 100nF.

5. The charging pile BMS power supply control circuit according to claim 4, characterized in that, The resistance of the third resistor (R3) is 0.2Ω.

6. The charging pile BMS power supply control circuit according to any one of claims 1 to 5, characterized in that, Both the first diode (D1) and the second diode (D2) are EM520 type diodes.

7. A DC charging pile, characterized in that, The application has the charging pile BMS power supply control circuit as described in any one of claims 1 to 6.

8. A charging system, characterized in that, The application includes the DC charging pile as described in claim 7.

9. The charging system according to claim 8, characterized in that, It also includes a server that communicates with the DC charging pile.

10. The charging system according to claim 9, characterized in that, The server and the DC charging pile are connected wirelessly.

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