An electric vehicle slow charging CP wake-up circuit with hardware self-locking function

Abstract

The application discloses a slow charging CP wake-up circuit with a hardware self-locking function for an electric vehicle, wherein the source of a MOS tube Q1 is connected with a vehicle storage battery, the drain is connected with a BMS power supply, and the gate is connected with the collector of an NPN triode Q2; the base of the NPN triode Q2 is connected with a slow charging gun CP signal transmitting end, and the emitter is grounded; the emitter of a PNP triode Q3 is connected between a grounding capacitor C2 and a resistor R3, the collector is connected with a closed CP wake-up signal transmitting end, and the base is connected with the collector of an NPN triode Q4; the collector of the NPN triode Q4 is connected with the emitter of the PNP triode Q3, the emitter is grounded, and the base is connected with the collector of the PNP triode Q3. The application controls the conduction state between the storage battery and the BMS power supply through cooperation of the slow charging gun CP signal transmitting end and the MOS tube, the closed CP wake-up signal transmitting end of the BMS outputs a high-level signal to close the CP wake-up, and a self-locking circuit is formed by the PNP triode Q3 and the NPN triode Q4, so that the BMS system power-off function after slow charging is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of electric vehicles, and in particular relates to an electric vehicle slow-charging CP wake-up circuit with a hardware self-locking function. Background Art

[0002] According to GBT 18487.1-2015 Electric Vehicle Conductive Charging System Part 1 General Requirements, after the slow charging pile completes charging, the CP signal changes from a PWM signal to a 12V high-level signal. The two existing CP wake-up circuits have the following problems.

[0003] ① Use an RC integral filter circuit to implement the CP wake-up function. The problem with this circuit is that after slow charging is completed, CP is a 9V duty cycle signal. This signal will continue to wake up the battery management system. If the slow charging gun is not unplugged for a long time, it may cause the electric vehicle's 12V lead-acid battery to run out of power. The next time the customer uses the vehicle, the vehicle will not be able to start, causing customer complaints.

[0004] ② Use the differential circuit unit to implement the CP wake-up function. The capacitor in the differential circuit unit lacks a discharge circuit. When the customer unplugs the slow charging gun for some reason and then plugs it back in, the internal charge of the capacitor in the differential circuit is not discharged, which will cause the wake-up function to fail, causing customer complaints.

[0005] The existing CP wake-up ① uses an RC integral circuit unit to implement the CP wake-up function. The secondary circuit problem is that after slow charging is completed, the CP is at a high level of 12V and continues to wake up the battery management system. If the slow charging gun is not unplugged for a long time, it may cause the electric vehicle's 12V lead-acid battery to run out of power. The next time the customer uses the vehicle, the vehicle cannot be started, causing customer complaints.

[0006] In order to solve the above problems, a slow charging CP wake-up circuit for electric vehicles with a hardware self-locking function is now proposed. Summary of the Invention

[0007] The purpose of the present invention is to provide an electric vehicle slow charging CP wake-up circuit with a hardware self-locking function. The conduction state between the battery and the BMS power supply is controlled by setting a slow charging gun CP signal transmitter and a MOS tube. The BMS's closed CP wake-up signal transmitter outputs a high-level signal to turn off CP wake-up, and a self-locking circuit is formed by a PNP transistor Q3 and an NPN transistor Q4 to realize the BMS system power-off function after slow charging is completed.

[0008] To solve the above technical problems, the present invention is achieved through the following technical solutions:

[0009] The present invention is a slow-charging CP wake-up circuit for electric vehicles with a hardware self-locking function, comprising a CP wake-up circuit and a self-locking circuit; the CP wake-up circuit comprises a MOS transistor Q1 and an NPN transistor Q2; the source of the MOS transistor Q1 is connected to the negative electrode of the anti-reverse connection diode D1; the positive electrode of the anti-reverse connection diode D1 is connected to the vehicle battery; the drain of the MOS transistor Q1 is connected to the BMS power supply; the gate of the MOS transistor Q1 is connected in series with a resistor R2 to the collector of the NPN transistor Q2 .... The base of transistor Q2 is connected in series with resistors R9 and R3 to the negative electrode of anti-reverse polarity diode D2, and the positive electrode of anti-reverse polarity diode D2 is connected to the CP signal transmitting end of slow charging gun; the emitter of NPN transistor Q2 is grounded; a resistor R5 is connected in series between the emitter and base of NPN transistor Q2; the resistor R5 and resistor R9 form a voltage divider circuit; a grounded capacitor C2 is connected between the resistor R9 and resistor R3; the grounded capacitor C2 and resistor R3 form an RC filter circuit to connect the slow charging gun CP The CP duty cycle signal transmitted by the signal transmitting end is converted into a high-level signal; the self-locking circuit includes a PNP transistor Q3 and an NPN transistor Q4; the emitter of the PNP transistor Q3 is connected between the grounding capacitor C2 and the resistor R3; the collector of the PNP transistor Q3 is connected to the negative electrode of the anti-reverse diode D3; the anode of the anti-reverse diode D3 is connected in series with a current limiting resistor R7 to the BMS shutdown CP wake-up signal transmitting end; the base of the PNP transistor Q3 is connected to the collector of the NPN transistor Q4 The CP wake-up signal transmitter outputs a CP_OFF ​​signal; the collector of the NPN transistor Q4 is further connected in series with a resistor R6 to the emitter of the PNP transistor Q3; a capacitor C3 is connected in parallel at both ends of the resistor R6; the emitter of the NPN transistor Q4 is grounded; the base of the NPN transistor Q4 is connected to the collector of the PNP transistor Q3; a resistor R8 is connected in series between the base and the emitter of the NPN transistor Q4, and a capacitor C4 is connected in parallel at both ends of the resistor R8.

[0010] Furthermore, a grounding capacitor C1 is connected between the drain of the MOS transistor Q1 and the BMS power supply.

[0011] Furthermore, a resistor R1 is connected in series between the gate and source of the MOS transistor Q1.

[0012] Furthermore, the slow charging gun CP signal transmitting end is also connected in series with a resistor R4 to the grounding module.

[0013] The present invention has the following beneficial effects:

[0014] The present invention controls the conduction state between the battery and the BMS power supply through the cooperation of the slow charging gun CP signal transmitting end and the MOS tube. The BMS shutdown CP wake-up signal transmitting end outputs a high-level signal to turn off CP wake-up, and a self-locking circuit is formed by the PNP transistor Q3 and the NPN transistor Q4 to realize the BMS system power-off function after the slow charging is completed.

[0015] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. 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 creative work.

[0017] Figure 1 This is a circuit diagram of an electric vehicle slow-charging CP wake-up circuit with a hardware self-locking function. DETAILED DESCRIPTION

[0018] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0019] See also Figure 1 As shown, the present invention is a slow-charging CP wake-up circuit for an electric vehicle with a hardware self-locking function, including a CP wake-up circuit and a self-locking circuit; the CP wake-up circuit includes a MOS transistor Q1 and an NPN transistor Q2; the source of the MOS transistor Q1 is connected to the cathode of the anti-reverse polarity diode D1; the anode of the anti-reverse polarity diode D1 is connected to the vehicle battery; the drain of the MOS transistor Q1 is connected to the BMS power supply; a resistor R2 is connected in series with the gate of the MOS transistor Q1 and connected to the collector of the NPN transistor Q2; a resistor R1 is further connected in series between the gate and source of the MOS transistor Q1; and a grounding capacitor C1 is further connected between the drain of the MOS transistor Q1 and the BMS power supply.

[0020] The base of the NPN transistor Q2 is connected in series with resistors R9 and R3, and then to the cathode of the anti-reverse polarity diode D2. The anode of the anti-reverse polarity diode D2 is connected to the CP signal transmitter of the slow charging gun. The emitter of the NPN transistor Q2 is grounded. A resistor R5 is also connected in series between the emitter and base of the NPN transistor Q2. The resistors R5 and R9 form a voltage divider circuit.

[0021] A grounded capacitor C2 is connected between resistor R9 and resistor R3; the grounded capacitor C2 and resistor R3 form an RC filter circuit to convert the CP duty cycle signal transmitted by the slow charging gun CP signal transmitter into a high-level signal; the slow charging gun CP signal transmitter is also connected in series with a resistor R4 to the ground module;

[0022] The self-locking circuit includes a PNP transistor Q3 and an NPN transistor Q4; the emitter of the PNP transistor Q3 is connected between the grounded capacitor C2 and the resistor R3; the collector of the PNP transistor Q3 is connected to the negative electrode of the anti-reverse polarity diode D3; the anode of the anti-reverse polarity diode D3 is connected in series with a current limiting resistor R7 to the BMS's closed CP wake-up signal transmitter; the base of the PNP transistor Q3 is connected to the collector of the NPN transistor Q4; the closed CP wake-up signal transmitter outputs a CP_OFF ​​signal; the collector of the NPN transistor Q4 is also connected in series with a resistor R6 to the emitter of the PNP transistor Q3; a capacitor C3 is connected in parallel at both ends of the resistor R6; the emitter of the NPN transistor Q4 is grounded; the base of the NPN transistor Q4 is connected to the collector of the PNP transistor Q3; a resistor R8 is connected in series between the base and the emitter of the NPN transistor Q4, and a capacitor C4 is connected in parallel at both ends of the resistor R8.

[0023] Among them, MOS tube Q1 is a P-channel MOS tube; pin 1 of MOS tube Q1 is the gate, pin 2 is the drain, and pin 3 is the source;

[0024] Pin 1 of the NPN transistor Q1, NPN transistor Q2, PNP transistor Q3 and NPN transistor Q4 is the base, pin 2 is the emitter, and pin 3 is the collector.

[0025] Example 1: This example is a working principle of an electric vehicle slow charging CP wake-up circuit with a hardware self-locking function: when the vehicle is plugged into a slow charging gun, the CP duty cycle signal passes through the anti-reverse polarity diode D2 and then is converted into a WAK_UP high-level signal by the RC filter circuit composed of resistor R3 and capacitor C2. The WAKE_UP high-level signal passes through the voltage divider circuit composed of resistor R9 and resistor R5 to turn on the NPN transistor Q2. The gate of the P-channel MOS transistor Q1 is turned on through the resistor R2 and the transistor Q2 to GND. The MOS transistor Q1 is turned on, and the 12V power supply of the car battery provides power to the BMS through the anti-reverse polarity diode D1 and the MOS transistor Q1. The BMS is awakened and the vehicle starts slow charging.

[0026] After the slow charging is completed, the BMS closing CP wake-up signal emission end outputs a CP OFF high level signal for closing the CP wake-up, the CP OFF signal passes through the current limiting resistor R7 and the anti-reverse connection diode D3 to turn on the NPN triode Q4, the PNP triode Q3 base is pulled down to GND through the PNP triode Q3, Q3 is turned on, the WAKE_UP signal is pulled down to GND through the PNP triode Q3 emitter and collector and the NPN triode Q4 base and emitter, at this time the WAKE_UP signal level is about 0.7V, after being divided by the resistor R9 and the resistor R5, it is not enough to turn on the NPN triode Q2, the NPN triode Q2 is closed, the MOS tube Q1 is pulled up to 12V by the resistor R1, the MOS tube Q1 is closed, the automobile storage battery 12V cannot supply power to the BMS power supply through the anti-reverse connection diode D1 and the MOS tube Q1, the BMS stops working, the CP OFF signal changes from high level to low level, at this time the triode Q4 and the triode Q3 are both in the conduction transition state, and interlocking is formed, the WAKE_UP signal is continuously pulled down, and the CP wake-up function is invalid. The BMS system power down function after the slow charging is completed is realized.

[0027] In the description of the present specification, the description referring to the terms "one embodiment", "an example", "a specific example" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0028] The preferred embodiments of the application disclosed above are only used to help explain the application. The preferred embodiments do not describe all the details and limit the application to the specific embodiments described. Obviously, many modifications and changes can be made according to the content of the present specification. The present specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the application, so that those skilled in the art can well understand and utilize the application. The application is limited only by the claims and their entire scope and equivalents.

Claims

1. A slow-charging CP wake-up circuit for electric vehicles with a hardware self-locking function, comprising a CP wake-up circuit and a self-locking circuit, characterized in that: The CP wake-up circuit includes a MOS transistor Q1 and an NPN transistor Q2; the source of the MOS transistor Q1 is connected to the cathode of the anti-reverse polarity diode D1; the anode of the anti-reverse polarity diode D1 is connected to the car battery; the drain of the MOS transistor Q1 is connected to the BMS power supply; the gate of the MOS transistor Q1 is connected in series with a resistor R2 to the collector of the NPN transistor Q2; The base of the NPN transistor Q2 is connected in series with resistors R9 and R3 to the cathode of the anti-reverse diode D2, and the anode of the anti-reverse diode D2 is connected to the CP signal transmitting end of the slow charging gun; The emitter of the NPN transistor Q2 is grounded; a resistor R5 is connected in series between the emitter and the base of the NPN transistor Q2; the resistor R5 and the resistor R9 form a voltage divider circuit; A grounded capacitor C2 is connected between the resistor R9 and the resistor R3; the grounded capacitor C2 and the resistor R3 form an RC filter circuit to convert the CP duty cycle signal transmitted by the slow charging gun CP signal transmitting end into a high-level signal; The self-locking circuit includes a PNP transistor Q3 and an NPN transistor Q4; the emitter of the PNP transistor Q3 is connected between the grounding capacitor C2 and the resistor R3; the collector of the PNP transistor Q3 is connected to the cathode of the anti-reverse polarity diode D3; the anode of the anti-reverse polarity diode D3 is connected in series with a current limiting resistor R7 to the BMS shutdown CP wake-up signal transmitter; the base of the PNP transistor Q3 is connected to the collector of the NPN transistor Q4; the shutdown CP wake-up signal transmitter outputs a CP_OFF ​​signal; The collector of the NPN transistor Q4 is further connected in series with a resistor R6 to the emitter of the PNP transistor Q3; a capacitor C3 is connected in parallel at both ends of the resistor R6; the emitter of the NPN transistor Q4 is grounded; and the base of the NPN transistor Q4 is connected to the collector of the PNP transistor Q3; A resistor R8 is connected in series between the base and emitter of the NPN transistor Q4 , and a capacitor C4 is connected in parallel at both ends of the resistor R8 .

2. The electric vehicle slow charging CP wake-up circuit with hardware self-locking function according to claim 1 is characterized in that: A grounding capacitor C1 is connected between the drain of the MOS transistor Q1 and the BMS power supply.

3. The electric vehicle slow charging CP wake-up circuit with hardware self-locking function according to claim 1 is characterized in that: A resistor R1 is connected in series between the gate and source of the MOS transistor Q1 .

4. The electric vehicle slow charging CP wake-up circuit with hardware self-locking function according to claim 1 is characterized in that: The slow charging gun CP signal transmitting end is further connected in series with a resistor R4 to the grounding module.

Images