Self-closing awakening CC detection awakening circuit, vehicle and control method

Abstract

The invention provides a self-closing awakening CC detection awakening circuit, a vehicle and a control method.The self-closing awakening CC detection awakening circuit comprises an awakening switch driving circuit, a DCDC circuit, a reference signal generating circuit, a CC signal sampling circuit, an awakening signal generating circuit, a control module and a latch switch circuit; the CC wake-up self-closing function is realized through the latch switch, that is, the control module drives the latch switch to enter a latch state after charging is finished, so that CC wake-up is closed to enable the control module system to enter a dormant state, and the power consumption current of the system meets the standard requirement of the dormant state; and the latch switch is powered down through the gun pulling action of the charging gun to exit from the latch state, so that the closing of the CC wake-up function is relieved, and the scheme has the advantages of simple circuit, low cost, simple logic, high reliability and the like.

Description

Technical Field

[0001] The present invention relates to the field of electric vehicles, and in particular to a CC detection wake-up circuit for self-shutdown wake-up, a vehicle and a control method. Background Art

[0002] Like traditional energy vehicles, EV new energy vehicles have a low-voltage starting battery (hereinafter referred to as: starting battery). In EV new energy vehicles, the starting battery is not only the starting power source of the vehicle, but also the low-voltage control system of the vehicle (hereinafter referred to as: control system) needs it to start. After the system starts, the DCDC will power the control system. At this time, the starting battery serves as the backup power source of the control system to ensure the reliability of the control system power supply, which is very important for the driving safety of the vehicle. In order to ensure that the vehicle can be reliably started when it is not used for a long time and then used again, and to ensure the reliability and life of the starting battery, when the vehicle is not in use, the control system of the vehicle should be in an extremely low power consumption state. In the relevant standards for EV new energy vehicles, this state is called the dormant state. The standard stipulates that when the vehicle is in the dormant state, the input power current of the control system must be ≤1mA.

[0003] When the control system enters the startup state from the sleep state, a wake-up signal is required to activate the system. The wake-up signals of the whole vehicle generally include CC, CP, CAN, DCDC power-on, VCU wake-up, and AC power-on to adapt to different models and application scenarios. CC and CP are handshake signals between the vehicle charging port and the charging gun of the charging pile. Their functions include: 1. Let the vehicle and the charging pile confirm whether the charging interface is successfully connected; 2. The CC signal also transmits information about the rated current level of the connected charging gun to the vehicle; 3. The CP signal transmits information about the maximum current that the charging gun can now deliver to the vehicle through the duty cycle of the PWM signal. Therefore, these two signals are necessary signals for charging EV new energy vehicles, and are also used to wake up the system during charging. In actual application, one of these two signals can be used as a wake-up signal, but due to different considerations, some car companies choose to use the CP signal as the wake-up signal during charging, while some car companies choose the CC signal. Therefore, when designing OBC or an integrated power system with OBC, OBC manufacturers design both CC and CP as system wake-up signals to adapt to different customers.

[0004] When the vehicle is charged using OBC with CC wake-up, due to the long charging time, the owner generally does not wait for the charging to be completed by the vehicle. When charging is completed, the charging gun is still plugged into the vehicle's charging port, and the CC wake-up signal cannot be turned off, making the system unable to enter the sleep state. The starting battery outputs useless power at this time, wasting the starting battery's power in vain. This will affect the performance, life and reliability of the starting battery in the long run.

[0005] The principle of the AC charging pile and vehicle connection interface is as follows Figure 1 Shown in the middle dotted box.

[0006] AC charging gun head ( Figure 1 Vehicle plug in the charging station Figure 1 The power supply equipment in the vehicle is connected, and the vehicle charging socket (hereinafter referred to as: vehicle socket) is on the vehicle. There are seven contacts ①-⑦ between the two. Among them, ①-④ are L1, L2, L3, N three-phase AC live wire and neutral wire respectively. If it is a single-phase charging pile, L2 and L3 are empty. ⑤ is the protective ground PE, which is also the power ground of the vehicle's low-voltage control system. ⑥ is the CC signal, ⑦ CP signal. The resistor RCC is connected between PE and CC on this side of the charging gun head. RCC is formed by R4 in parallel with S3 and then in series with RC.

[0007] S3 is the button switch on the handle of the charging gun. When in use, the button must be turned on to insert the charging gun plug into the car socket. When the button is not closed after inserting into the car socket, it is defined as a semi-connected state. At this time, S3 is in a disconnected state, and the resistance between PE and CC is R4+RC, with a resistance value of approximately 3.3kΩ. The connection is completed only when the handle button is pressed and closed. At this time, S3 is in a closed state, and the resistance between PE and CC is RC. The RC resistance values ​​of AC charging guns with rated currents of 10A / 16A / 32A / 63A are 1.5kΩ / 680Ω / 220Ω / 100Ω respectively.

[0008] The vehicle side determines whether the charging gun is plugged in, in a semi-connected state, or fully connected by detecting the resistance values ​​of PE and CC. After the connection is completed, the rated current level of the charging gun is determined based on the resistance value of CC. If CC has a wake-up function, the system should be awakened after the gun is plugged in.

[0009] The working principle of CC detection and wake-up circuit without self-shutdown wake-up function is as follows Figure 2 As shown in the figure, the circuit hardware connection relationship is as follows: the circuit is powered by a starting battery, and the positive and negative output terminals of the starting battery are Bat_V+ and PE in the figure respectively (the negative terminal of the starting battery is connected to PE in the vehicle). The circuit module consists of functional circuits F1-F8 and system control microcontroller MCU1. Their basic connections are as follows: Figure 2 shown.

[0010] F1 is the power input filter circuit, which is used to improve the EMC performance of the system. Its input is Bat_V+ and PE, and its output is Bat_V+1 and SYS_GND. For DC signals, Bat_V+ and Bat_V+1 are at the same potential, and PE and SYS_GND are also at the same potential.

[0011] F2 is the system wake-up switch and its driving circuit, which consists of Q1, Q2, R2, R5, R6, and C5. Q1 is the PMOS tube main power switch, Q2 is the npn signal transistor and together with R2, R5, R6, and C5 constitute the driving circuit of Q1. When the CC wake-up signal CC_EN is high, Q1 is turned on, Bat_V+1 is connected to SYS_V+, and the system is powered on and starts working. When CC_EN is low, Q1 is turned off, Bat_V+1 is disconnected from SYS_V+, and the system loses power and enters a dormant state.

[0012] F3 is a DCDC functional module, which is used to reduce SYS_V+ to the regulated output SYS_+5V. F3 is composed of C1, U1, and C2. U1 can be an LDO or a high-frequency DCDC. SYS_+5V is mainly used to power the system MCU1 and some peripheral circuits.

[0013] F4 is a low-power linear reference voltage regulator circuit composed of U3 (low-power LDO), C10, and C9. This circuit converts Bat_V+1 into a stable CC_5V as a standard voltage source for CC state detection. The power supply takes 5V to meet the lower limit of the starting battery operating voltage, and can also increase the higher voltage level to help improve the circuit's anti-interference performance.

[0014] F5 is the CC wake-up comparison reference signal CC_ref generating circuit. CC_5V is divided by R11 and R14 and then filtered by C7 to improve the anti-interference ability to form CC_ref, so that the system input current in the sleep state meets the standard.

[0015] F6 is the CC signal sampling circuit. CC_5V is divided by R9 and R_CC (resistance between CC and PE) and then filtered by R10 and C6 to form the CC signal CC_V.

[0016] F7 is the circuit for generating the CC wake-up signal CC_EN, which consists of a low-power OC output comparator U4A and a power pull-up resistor R8. U4A is powered by Bat_V+1 and SYS_GND, and R8 is also pulled up to Bat_V+1.

[0017] F8 is the signal conditioning circuit for AD sampling of CC_V signal. It consists of a general-purpose operational amplifier U2A, a signal follower composed of R4 and R1, and an RC filter composed of R3 and C4. Its input is CC_V and its output is AD_CC_V. The control module MCU1 is the system microcontroller, and the output signal AD_CC_V of F8 is sent to an AD conversion port of MCU1.

[0018] Its working principle is briefly described as follows: F4, F5, F6, and F7 in the circuit are all powered by Bat_V+1, that is, these circuits need to work when the system is in sleep or working state. Therefore, U3 and U4A generally use low-power devices, and R11 and R14 need larger resistances to ensure that the system current meets the requirements in sleep state.

[0019] The output voltage CC_5V of F4 is 5V. CC_5V is divided by R11 and R14 to generate CC_ref. A higher CC_ref voltage value helps the circuit to detect interference. For example, 3.5V is used here.

[0020] When the car is not plugged in the charging gun, the resistance R_CC is infinite, CC_V is 5V>CC_ref, the output signal CC_EN of F7 is low, the system is in sleep state, CC_EN is low, R8 will be connected between Bat_V+1 and SYS_GND to generate current, so R8 should also be selected with a larger resistance to ensure that the system current meets the requirements of the sleep state. When the car is plugged in the charging gun, the resistance R_CC is no longer infinite, R9 will divide the voltage with R_CC, so that CC_V<CC_ref, and the output signal CC_EN of F7 turns to a high level.

[0021] When CC_EN is at a low level, Q2 of F2 is not conducting, so Q1 is also not conducting, and the system is in a dormant state. When CC_EN is at a high level, Q2 of F2 is conducting, so Q1 is also conducting, and the system is powered on and enters a working state.

[0022] When the system enters the working state, both F8 and MCU1 must be powered on. MCU1 collects the output signal AD_CC_V of F8 and identifies based on this signal: 1. The charging gun is in a semi-connected or connected state at this time; 2. The rated current level of the charging gun. In order to have better resolution and anti-interference ability of AD_CC_V, the CC_V signal after the gun is plugged in should be less than but as close to CC_5V as possible; at the same time, in order to ensure that CC_EN can be in different states when the gun is not plugged in and when the gun is plugged in, the maximum value of CC_V after the gun is plugged in should be less than CC_ref by about 0.6V~0.8V.

[0023] When OBC completes charging, since the CC_EN wake-up signal cannot be turned off, MCU1 can only select a product with low power consumption function. After OBC completes charging, MCU1 enters a low power consumption state to reduce the power consumption of the system in this state.

[0024] The above existing solutions have the following problems: since the CC wake-up function cannot be turned off automatically to put the system into a sleep state, the MCU can only be put into a low-power state to put the system into a relatively low-power state to save the performance of the startup battery. This state is referred to as the low-power state to distinguish it from the sleep state.

[0025] When the system is in a low power state, the MCU still needs a power supply current of several hundred uA-2mA, and the MCU peripheral circuits such as Figure 2 F8 in the circuit cannot be turned off. In fact, there are multiple functional circuits like F8 in the complete system, all of which consume about 1mA of current. Thirdly, the F6 circuit also consumes 1.1-1.6mA of current.

[0026] Therefore, the system still needs to consume about 10mA of current in the low power state, which is higher than the power consumption current of ≤1mA required in the sleep state. If the system can automatically turn off the CC wake-up function at this time, the performance of the startup battery can be better saved and utilized. Summary of the invention

[0027] The first object of the present invention is to provide a CC detection wake-up circuit which automatically turns off the wake-up function after charging is completed.

[0028] A second object of the present invention is to provide a vehicle having the above CC detection wake-up circuit.

[0029] A third object of the present invention is to provide a control method for the CC detection wake-up circuit.

[0030] In order to achieve the first objective of the present invention, the present invention provides a CC detection wake-up circuit for self-shutdown wake-up, including a wake-up switch driving circuit, a DCDC circuit, a reference signal generating circuit, a CC signal sampling circuit, a wake-up signal generating circuit and a control module, the wake-up switch driving circuit includes a main power switch and a switch driving circuit, the input end of the main power switch is used to receive a DC signal connection, the switch driving circuit is connected to the main power switch and controls the on and off of the main power switch, the switch driving circuit is used to receive a CC wake-up signal, the output end of the main power switch is connected to the input end of the DCDC circuit, and the output end of the DCDC circuit is connected to the power supply end of the control module; the input end of the reference signal generating circuit is connected to a standard voltage source and receives a standard voltage, the CC signal sampling circuit includes a first resistor, a second resistor and a first capacitor, the first end of the first resistor is connected to the standard voltage source and receives the standard voltage, the output end of the reference signal generating circuit is connected to the first end of the first resistor and the reference signal end for outputting a reference signal, the second end of the first resistor is connected to the first end of the second resistor and the CC detection end, and the second end of the second resistor is connected to the first capacitor The first end of the first capacitor is connected to the CC signal end, and the second end of the first capacitor is grounded; the wake-up signal generating circuit includes a first comparator, the first input end of the first comparator is connected to the CC signal end, the second input end of the first comparator is connected to the reference signal end of the reference signal generating circuit and receives the reference signal output by the reference signal generating circuit, the output end of the first comparator is connected to the CC wake-up end of the switch driving circuit and outputs a CC wake-up signal to the switch driving circuit; the CC detection wake-up circuit also includes a latch switch circuit, the latch switch circuit includes a third resistor, a fourth resistor, a fifth resistor, a first transistor, a second transistor and a second capacitor, the first end of the third resistor is connected to the control module and is used to receive the CC enable signal, the second end of the third resistor is connected to the collector of the first transistor, the base of the second transistor, the first end of the fourth resistor, and the first end of the second capacitor, the emitter of the second transistor, the second end of the fourth resistor and the second end of the second capacitor are grounded, the base of the first transistor is connected to the collector of the second transistor and the first end of the fifth resistor, and the emitter of the first transistor is connected to the second end of the fifth resistor and the CC signal end.

[0031] It can be seen from the above scheme that after the OBC completes charging, the problem of realizing the CC wake-up self-closing function can be cleverly solved through the latch switch circuit, that is, after the charging is completed, the control module drives the latch switch to enter the latch state, thereby turning off the CC wake-up and allowing the control module system to enter the sleep state. The system power consumption current meets the standard requirements of the sleep state, and then the latch switch can be powered off and exit the latch state by pulling out the charging gun, thereby releasing the CC wake-up function. This scheme has the advantages of simple circuit, low cost, concise logic and high reliability.

[0032] A further solution is that the CC detection wake-up circuit also includes a sampling reference voltage switching circuit, the sampling reference voltage switching circuit includes a first field effect transistor, a sixth resistor and a seventh resistor, the source of the first field effect transistor is connected to the first end of the sixth resistor and the input end of the DCDC circuit, the gate of the first field effect transistor is connected to the second end of the sixth resistor and the first end of the seventh resistor, and the second end of the seventh resistor is connected to the output end of the DCDC circuit; the CC signal sampling circuit also includes an eighth resistor, the first end of the eighth resistor is connected to the input end of the reference signal generating circuit, and the second end of the eighth resistor is connected to the first end of the first resistor and the drain of the first field effect transistor.

[0033] A further solution is that the CC detection wake-up circuit also includes a signal conditioning circuit, the signal conditioning circuit includes an operational amplifier, a ninth resistor and a tenth resistor, the ninth resistor is connected between the CC signal terminal and the positive input terminal of the operational amplifier, the tenth resistor is connected between the output terminal and the negative input terminal of the operational amplifier, and the output terminal of the operational amplifier is connected to the control module.

[0034] A further solution is that the signal conditioning circuit includes an eleventh resistor and a third capacitor, the first end of the eleventh resistor is connected to the output end of the operational amplifier, the second end of the eleventh resistor is connected to the first end of the third capacitor and the control module, and the second end of the third capacitor is grounded.

[0035] As can be seen from the above, the CC_V signal AD can be sampled through the signal conditioning circuit, which can effectively obtain the rated current level of the charging gun, and through the arrangement of the sampling reference voltage switching circuit, the first field effect tube is driven to turn on after the sampling reference voltage switching circuit is energized, so the CC_V signal is generated through the first resistor and the voltage divider of the charging gun, and when the CC wake-up self-closing state is realized, the CC signal sampling circuit is in a low power consumption state, and the power supply current of the CC signal sampling circuit is less than 20uA, which has the advantages of simple circuit, reliability and low cost.

[0036] A further solution is that the CC detection wake-up circuit includes a power input filter circuit, which is connected between the input end of the main power switch and the DC power supply, and the power input filter circuit outputs a DC signal to the input end of the main power switch.

[0037] A further solution is that the CC detection wake-up circuit includes a reference voltage regulator circuit, which is connected between the input end of the reference signal generating circuit and the standard voltage source, and the reference voltage regulator circuit outputs a stabilized standard voltage to the input end of the reference signal generating circuit.

[0038] It can be seen from the above that, through the arrangement of the filter circuit and the reference voltage regulator circuit, the voltage input to the wake-up switch driving circuit and the reference signal generating circuit is stable.

[0039] A further solution is that the switch driving circuit includes a third transistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor and a fourth capacitor, the main power switch adopts a second field effect transistor, the input end of the main power switch is the source of the second field effect transistor, the source of the second field effect transistor is connected to the first end of the twelfth resistor, the output end of the main power switch is the drain of the second field effect transistor, the gate of the second field effect transistor is connected to the second end of the twelfth resistor and the first end of the thirteenth resistor, the second end of the thirteenth resistor is connected to the collector of the third transistor, the base of the third transistor is connected to the first end of the fourteenth resistor and the first end of the fourth capacitor, the second end of the fourteenth resistor is connected to the CC wake-up end, and the emitter of the third transistor and the second end of the fourth capacitor are grounded.

[0040] It can be seen from the above that, through the arrangement of the switch driving circuit and the second field effect transistor, the switching on and off of the main power switch can be achieved stably and efficiently.

[0041] In order to achieve the second objective of the present invention, the present invention provides a vehicle, comprising a CC detection wake-up circuit as described above.

[0042] In order to achieve the third objective of the present invention, the present invention provides a control method for the CC detection wake-up circuit applied to the above-mentioned scheme, and the control method includes: When the charging gun is inserted and connected to the CC detection end, the voltage of the reference signal end is greater than the voltage of the CC signal end, and the output end of the first comparator outputs a CC wake-up signal to the switch drive circuit. The switch drive circuit controls the conduction of the main power switch according to the CC wake-up signal. After receiving the DC signal, the DCDC circuit supplies power to the control module, and the control module is awakened and enters the charging state. When charging is completed, the control module outputs a CC enable signal to the first end of the third resistor, the first transistor and the second transistor remain in the on state, the first transistor reverses the level state of the CC signal end, and then blocks the main power switch, the control module loses power and enters a sleep state.

[0043] A further solution is that when the charging gun is unplugged, the CC detection end is idle, the voltage at the reference signal end is lower than the voltage at the CC signal end, the output end of the first comparator outputs a shutdown signal to the switch drive circuit, the latch switch circuit loses power, resets and releases the latch state, and the control module releases the CC wake-up self-closing state and enters a sleep state without a gun plugged in.

[0044] As can be seen from the above, in addition to completing OBC charging when the charging gun is normally plugged in, this case also implements the CC wake-up self-closing function through the latch switch, that is, after the charging is completed, the control module drives the latch switch to enter the latch state, thereby closing the CC wake-up and allowing the control module system to enter the sleep state. The system power consumption current meets the standard requirements of the sleep state, and then the latch switch can be powered off and exit the latch state by pulling out the charging gun, thereby releasing the CC wake-up function. This solution has the advantages of simple circuit, low cost, concise logic and high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a schematic diagram of the connection interface between an AC charging pile and a vehicle in the prior art.

[0046] Figure 2 The invention is a circuit schematic diagram of a CC detection wake-up circuit without a self-shutdown wake-up function in the prior art.

[0047] Figure 3 4 is a circuit schematic diagram of an embodiment of a CC detection wake-up circuit of the present invention.

[0048] Figure 4 yes Figure 3 The circuit schematic diagram of the F1-F3 functional modules.

[0049] Figure 5 yes Figure 3 The circuit schematic diagram of the F4-F10 functional modules.

[0050] Figure 6 It is a flow chart of an embodiment of a control method of a CC detection wake-up circuit of the present invention.

[0051] The present invention is further described below in conjunction with the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0052] Reference Figures 3 to 5 The CC detection wake-up circuit includes a power input filter circuit F1, a wake-up switch driving circuit F2, a DCDC circuit F3, a reference voltage regulator circuit F4, a reference signal generating circuit F5, a CC signal sampling circuit F6, a wake-up signal generating circuit F7, a control module MCU1, a signal conditioning circuit F8, a sampling reference voltage switching circuit F9 and a latch switch circuit F10.

[0053] The power input filter circuit F1 is connected between the input end of the main power switch and the DC power supply. The power input filter circuit F1 includes inductors L1, L2 and capacitor C3. The power input filter circuit F1 outputs a DC signal to the input end of the main power switch. The first end of the inductor L1 is connected to the positive electrode of the starting battery, and the first end of the inductor L2 is connected to PE, which is also the negative electrode of the starting battery connected to the vehicle body ground.

[0054] The wake-up switch driving circuit F2 includes a main power switch and a switch driving circuit. The input end of the main power switch is used to receive a DC signal connection. The switch driving circuit is connected to the main power switch and controls the on and off of the main power switch. The switch driving circuit is used to receive a CC wake-up signal. The output end of the main power switch is connected to the input end of the DCDC circuit F3. The output end of the DCDC circuit F3 is connected to the power supply end of the control module MCU1. Specifically, the switch driving circuit includes a third transistor Q3, a twelfth resistor R2, a thirteenth resistor R5, a fourteenth resistor R6 and a fourth capacitor. The main power switch adopts the second field effect transistor Q1. The input end of the main power switch is the source of the second field effect transistor Q1. The source of the second field effect transistor Q1 is connected to the first end of the twelfth resistor R2 and the second end of the inductor L1. The output end of the main power switch is the drain of the second field effect transistor Q1. The gate of the second field effect transistor Q1 is connected to the second end of the twelfth resistor R2 and the first end of the thirteenth resistor R5. The second end of the thirteenth resistor R5 is connected to the collector of the third transistor Q3. The base of the third transistor Q3 is connected to the first end of the fourteenth resistor R6 and the first end of the fourth capacitor. The second end of the fourteenth resistor R6 is connected to the CC wake-up end CC_EN. The emitter of the third transistor Q3 and the second end of the fourth capacitor are grounded.

[0055] The DCDC circuit F3 is composed of capacitor C1, chip U1, and capacitor C2. Chip U1 can be an LDO or a high-frequency DCDC. The function of the DCDC circuit F3 is to reduce SYS_V+ to the regulated output SYS_+5V. SYS_+5V is mainly used to power the system microcontroller MCU1 and some of its peripheral circuits.

[0056] The reference voltage regulator circuit F4 is connected between the input end of the reference signal generating circuit F5 and the second end of the inductor L1. The reference voltage regulator circuit F4 outputs a stabilized standard voltage to the input end of the reference signal generating circuit F5. The reference voltage regulator circuit F4 is a low-power linear reference voltage regulator circuit composed of a chip U3, a capacitor C10, and a capacitor C9. The chip U3 can use a low-power LDO. The reference voltage regulator circuit F4 converts Bat_V+1 into a stable CC_5V as a standard voltage source for CC state detection. The power supply takes 5V to meet the lower limit requirement of the starting battery working voltage, and can also increase the voltage level, which helps to improve the anti-interference performance of the circuit.

[0057] The input end of the reference signal generating circuit F5 is connected to the output end of the reference voltage stabilizing source circuit F4 and receives the stabilized standard voltage. The reference signal generating circuit F5 includes a resistor R11, a resistor R14 and a capacitor C7. The input end of the reference signal generating circuit F5 is the first end of the resistor R11. The first end of the resistor R11 is connected to the output end of the reference voltage stabilizing source circuit F4 and the first end of the eighth resistor R12. The second end of the resistor R11 is connected to the first end of the resistor R14, the first end of the capacitor C7 and the reference signal end CC_ref. The second end of the resistor R14 and the second end of the capacitor C7 are grounded. The reference signal generating circuit F5 is a CC wake-up comparison reference signal CC_ref generating circuit. CC_5V is divided by R11 and R14 and then filtered by C7 to improve the anti-interference ability to form CC_ref. In order to make the system input current meet the standard in the sleep state, the resistance values ​​of R11 and R14 are preferably hundreds of KΩ.

[0058] The CC signal sampling circuit F6 includes a first resistor R9, a second resistor R10, a first capacitor C6 and an eighth resistor R12, the second end of the eighth resistor R12 is connected to the first end of the first resistor R9 and the drain of the first field effect transistor Q4, the second end of the first resistor R9 is connected to the first end of the second resistor R10 and the CC detection end (CC), the second end of the second resistor R10 is connected to the first end of the first capacitor C6 and the CC signal end CC_V, and the second end of the first capacitor C6 is grounded. Preferably, the resistance value of the resistor R12 is not less than 200kΩ, the resistor R12 is connected in series before the resistor R9, and the network connected between them is named CC_5Va.

[0059] The wake-up signal generating circuit F7 includes a first comparator U4A, a first input end of the first comparator U4A is connected to the CC signal end CC_V, a second input end of the first comparator U4A is connected to the reference signal end CC_ref of the reference signal generating circuit F5 and receives the reference signal output by the reference signal generating circuit F5, an output end of the first comparator U4A is connected to the CC wake-up end CC_EN of the switch driving circuit and outputs a CC wake-up signal to the switch driving circuit, the first comparator U4A adopts a low-power OC output comparator, the first comparator U4A is composed of a power pull-up resistor R8, U4A is powered by Bat_V+1 and SYS_GND, and the resistor R8 is also pulled up to Bat_V+1.

[0060] The signal conditioning circuit F8 includes an operational amplifier U2A, a ninth resistor R4, a tenth resistor R1, an eleventh resistor R3 and a third capacitor C4. The ninth resistor R4 is connected between the CC signal terminal CC_V and the positive input terminal of the operational amplifier U2A, the tenth resistor R1 is connected between the output terminal and the negative input terminal of the operational amplifier U2A, the first end of the eleventh resistor R3 is connected to the output terminal of the operational amplifier U2A, the second end of the eleventh resistor R3 is connected to the first end of the third capacitor C4 and the control module MCU1, and the second end of the third capacitor C4 is grounded. The signal conditioning circuit F8 is used for AD sampling of the CC_V signal, the signal follower formed by U2A, R4, and R1, and the RC filter formed by R3 and C4. The input of the signal conditioning circuit is CC_V, and the output is AD_CC_V. The control module MCU1 is a system single chip microcomputer, and the output signal AD_CC_V of F8 is sent to an AD conversion port of MCU1.

[0061] The sampling reference voltage switching circuit F9 includes a first field effect transistor Q4, a sixth resistor R13 and a seventh resistor R17. The source of the first field effect transistor Q4 is connected to the first end of the sixth resistor R13 and the input end SYS_V+ of the DCDC circuit F3. The gate of the first field effect transistor Q4 is connected to the second end of the sixth resistor R13 and the first end of the seventh resistor R17. The second end of the seventh resistor R17 is connected to the output end SYS_5V+ of the DCDC circuit F3. The sampling reference voltage switching circuit F9 is a circuit for realizing low power consumption of the CC sampling circuit when the CC wakes up from the self-off state. The circuit is composed of a signal NMOS first field effect transistor Q4, a sixth resistor R13, and a seventh resistor R17. The input (S pole) of Q4 is SYS_+5V, the G pole of Q4 is driven by SYS_V+, R13 and R17 are the driving circuit matching resistors of the first field effect transistor Q4, and the output (D pole) of Q4 is connected to CC_5Va of F6.

[0062] The latch switch circuit F10 includes a third resistor R16, a fourth resistor R15, a fifth resistor R7, a first transistor Q3, a second transistor Q5 and a second capacitor C8. The first end of the third resistor R16 is connected to the control module MCU1 and is used to receive a CC enable signal. The second end of the third resistor R16 is connected to the collector of the first transistor Q3, the base of the second transistor Q5, the first end of the fourth resistor R15, and the first end of the second capacitor C8. The emitter of the second transistor Q5, the second end of the fourth resistor R15, and the second end of the second capacitor C8 are grounded. The base of the first transistor Q3 is connected to the collector of the second transistor Q5 and the first end of the fifth resistor R7. The emitter of the first transistor Q3 is connected to the second end of the fifth resistor R7 and the CC signal terminal CC_V. u_shut_CC_EN is the CC enable signal sent by MCU1. R16 and C8 form a filter circuit for the u_shut_CC_EN signal. Q3, Q4, R7 and R15 form a latch switch. The first transistor Q3 can be a pnp signal transistor, and the second transistor Q5 can be an npn signal transistor. The input end of the latch switch circuit F10 is connected to the CC_EN end of the wake-up signal generating circuit F7.

[0063] See also Figure 6 The working principle of the CC detection wake-up circuit and its control method include the following steps.

[0064] At the beginning, step S11 is executed and the system is in a dormant state.

[0065] Then, step S12 is executed to determine whether the charging gun is plugged in. If the gun is not plugged in, the CC detection terminal (CC) is idle, then CC_V=5V, and then CC_V>CC_ref, so CC_EN is at a low level, so Q1 remains off and the system continues to remain in sleep mode.

[0066] Then execute step S13. When the charging gun is plugged in, the resistor R_CC on the charging gun is connected to the CC detection terminal (CC). At this time, CC_5V is divided by R12, R9, and R_CC to generate CC_V. Since the resistance value of R12 can be selected to be greater than the resistance value of R_CC, preferably R12=200kΩ, CC_V≈0V, then CC_V<CC_ref, CC_EN is high level, then Q1 is turned on, and the system is awakened and powered to enter the working state.

[0067] Then, step S14 is executed. After the system is awakened, SYS_V+ and SYS_+5V are both powered, and SYS_V+>SYS_+5V, the Vgs voltage of Q4 is positive, making Q4 turned on, and CC_V is generated by SYS_+5V through R9 and RCC. MCU1 performs AD sampling on CC_V at this time, and identifies the rated current specification of the charging gun according to the sampled voltage. Then, step S15 is executed, and the system performs other preparations before charging. Then, step S16 is executed to enter the charging state and start charging.

[0068] As step S17 is executed, it is in the charging state, and then step S18 is executed to determine whether the charging is completed. If not, the charging state is maintained and charging continues. If charging is completed, step S19 is executed, MCU1 changes the u_shut_CC_EN signal from low to high. The signal is low in the previous state. The latch switch circuit F10 turns on Q5 as a latch switch. After Q5 is turned on, Q3 is turned on. After Q3 is turned on, Q5 is kept on. At this time, even if u_shut_CC_EN is a low level, Q5 is kept on because Q3 is turned on. In this way, the latch switch enters a low-impedance latched on state. Previously, the latch switch was in a high-impedance off state. The conduction of Q5 and Q3 will pull CC_EN from a high level to a low level, and then Q1 is turned off, and then SYS_V+ and SYS_+5V lose power. The control module MCU1 loses power and enters a sleep state.

[0069] At this time, since SYS_V+ and SYS_+5V lose power, the Vgs voltage of Q4 is 0V, so Q4 is turned off, and then CC_V is converted to CC_5V through R12, R9, and R_CC voltage division. Since R12=200kΩ, the current of the voltage divider resistor network is less than 20uA, that is, the power supply current of the CC signal sampling circuit is less than 20uA at this time.

[0070] Then, step S20 is executed to maintain the CC wake-up self-closing sleep state, and then step S21 is executed to determine whether the gun is drawn. If not, the above CC wake-up self-closing sleep state continues to be maintained. If the gun is drawn, step S22 is executed. Since CC_V=5V, CC_V>CC_ref, the comparator U4A in F7 outputs a low-level shutdown signal, the latch switch of F10 loses power and resets to release the latch state, and then the CC wake-up self-closing state is released. The control module MCU1 releases the CC wake-up self-closing state and enters the sleep state without a gun.

[0071] The vehicle includes a CC detection wake-up circuit as in the above scheme, and the vehicle can be a new energy electric car, a new energy electric bus, a new energy electric truck, a new energy electric cleaning vehicle, a new energy electric rail transportation vehicle, a new energy electric flying vehicle, a new energy electric shipping vehicle, etc.

[0072] Of course, the above embodiments are only preferred embodiments of the present case, and may have more variations in specific applications. For example, in addition to using field effect transistors for on-off control, the main power switch may also use devices such as relays, and use other types of switch drive circuits to control the main power switch, which can also realize the on-off of the main power supply line. The above description of the connection may be a direct connection on the line or an indirect connection. According to the relevant functions and the purpose of realization, technical personnel in this field may perform wiring and connection according to actual conditions. The above changes are all within the protection scope of the present invention.

[0073] As can be seen from the above, in addition to realizing OBC charging when the charging gun is normally plugged in, this case also realizes the CC wake-up self-closing function through the latch switch, that is, after the charging is completed, the control module drives the latch switch to enter the latch state, thereby turning off the CC wake-up and allowing the control module system to enter the sleep state. The system power consumption current meets the standard requirements of the sleep state, and then the latch switch can be powered off and exit the latch state by pulling out the charging gun, thereby releasing the CC wake-up function. This solution has the advantages of simple circuit, low cost, simple logic and high reliability.

Claims

1. A CC detection wake-up circuit for self-shutdown wake-up, comprising a wake-up switch driving circuit, a DCDC circuit, a reference signal generating circuit, a CC signal sampling circuit, a wake-up signal generating circuit and a control module, wherein the wake-up switch driving circuit comprises a main power switch and a switch driving circuit, wherein the input end of the main power switch is used to receive a DC signal connection, the switch driving circuit is connected to the main power switch and controls the on and off of the main power switch, the switch driving circuit is used to receive a CC wake-up signal, the output end of the main power switch is connected to the input end of the DCDC circuit, and the output end of the DCDC circuit is connected to the power supply end of the control module; The input end of the reference signal generating circuit is connected to a standard voltage source and receives a standard voltage. The CC signal sampling circuit includes a first resistor, a second resistor and a first capacitor. The first end of the first resistor is connected to the standard voltage source and receives the standard voltage. The output end of the reference signal generating circuit is connected to the first end of the first resistor and the reference signal end for outputting a reference signal. The second end of the first resistor is connected to the first end of the second resistor and the CC detection end. The second end of the second resistor is connected to the first end of the first capacitor and the CC signal end. The second end of the first capacitor is grounded. The wake-up signal generating circuit comprises a first comparator, wherein a first input terminal of the first comparator is connected to the CC signal terminal, a second input terminal of the first comparator is connected to the reference signal terminal of the reference signal generating circuit and receives a reference signal output by the reference signal generating circuit, and an output terminal of the first comparator is connected to the CC wake-up terminal of the switch driving circuit and outputs a CC wake-up signal to the switch driving circuit; Features: The CC detection wake-up circuit also includes a latch switch circuit, which includes a third resistor, a fourth resistor, a fifth resistor, a first transistor, a second transistor and a second capacitor. The first end of the third resistor is connected to the control module and is used to receive a CC enable signal. The second end of the third resistor is connected to the collector of the first transistor, the base of the second transistor, the first end of the fourth resistor, and the first end of the second capacitor. The emitter of the second transistor, the second end of the fourth resistor and the second end of the second capacitor are grounded. The base of the first transistor is connected to the collector of the second transistor and the first end of the fifth resistor. The emitter of the first transistor is connected to the second end of the fifth resistor and the CC signal end.

2. The CC detection wake-up circuit according to claim 1, characterized in that: The CC detection wake-up circuit also includes a sampling reference voltage switching circuit, which includes a first field effect tube, a sixth resistor and a seventh resistor, wherein the source of the first field effect tube is connected to the first end of the sixth resistor and the input end of the DCDC circuit, the gate of the first field effect tube is connected to the second end of the sixth resistor and the first end of the seventh resistor, and the second end of the seventh resistor is connected to the output end of the DCDC circuit; The CC signal sampling circuit also includes an eighth resistor, a first end of the eighth resistor is connected to the input end of the reference signal generating circuit, and a second end of the eighth resistor is connected to the first end of the first resistor and the drain of the first field effect transistor.

3. The CC detection wake-up circuit according to claim 2, characterized in that: The CC detection wake-up circuit also includes a signal conditioning circuit, which includes an operational amplifier, a ninth resistor and a tenth resistor, wherein the ninth resistor is connected between the CC signal terminal and the positive input terminal of the operational amplifier, the tenth resistor is connected between the output terminal and the negative input terminal of the operational amplifier, and the output terminal of the operational amplifier is connected to the control module.

4. The CC detection wake-up circuit according to claim 3, characterized in that: The signal conditioning circuit includes an eleventh resistor and a third capacitor, the first end of the eleventh resistor is connected to the output end of the operational amplifier, the second end of the eleventh resistor is connected to the first end of the third capacitor and the control module, and the second end of the third capacitor is grounded.

5. The CC detection wake-up circuit according to claim 1, characterized in that: The CC detection wake-up circuit includes a power input filter circuit, which is connected between the input end of the main power switch and a DC power supply, and outputs a DC signal to the input end of the main power switch.

6. The CC detection wake-up circuit according to claim 1, characterized in that: The CC detection wake-up circuit includes a reference voltage regulator circuit, which is connected between the input end of the reference signal generating circuit and a standard voltage source, and outputs a stabilized standard voltage to the input end of the reference signal generating circuit.

7. The CC detection wake-up circuit according to any one of claims 1 to 6, characterized in that: The switch driving circuit includes a third transistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor and a fourth capacitor. The main power switch adopts a second field effect transistor. The input end of the main power switch is the source of the second field effect transistor, the source of the second field effect transistor is connected to the first end of the twelfth resistor, the output end of the main power switch is the drain of the second field effect transistor, the gate of the second field effect transistor is connected to the second end of the twelfth resistor and the first end of the thirteenth resistor, the second end of the thirteenth resistor is connected to the collector of the third transistor, the base of the third transistor is connected to the first end of the fourteenth resistor and the first end of the fourth capacitor, the second end of the fourteenth resistor is connected to the CC wake-up end, and the emitter of the third transistor and the second end of the fourth capacitor are grounded.

8. A means of transport, characterized in that The invention comprises a CC detection wake-up circuit as described in any one of claims 1 to 7.

9. The control method for the CC detection wake-up circuit according to any one of claims 1 to 7, characterized in that: The control method comprises: When the charging gun is inserted and connected to the CC detection end, the voltage of the reference signal end is greater than the voltage of the CC signal end, the output end of the first comparator outputs a CC wake-up signal to the switch drive circuit, and the switch drive circuit controls the conduction of the main power switch according to the CC wake-up signal. After receiving the DC signal, the DCDC circuit supplies power to the control module, and the control module is awakened and enters the charging state; When charging is completed, the control module outputs a CC enable signal to the first end of the third resistor, the first transistor and the second transistor remain in the on state, the first transistor reverses the level state of the CC signal end, and then blocks the main power switch, and the control module loses power and enters a sleep state.

10. The control method according to claim 9, characterized in that: When the charging gun is unplugged, the CC detection end is idle, the voltage of the reference signal end is lower than the voltage of the CC signal end, the output end of the first comparator outputs a shutdown signal to the switch drive circuit, the latch switch circuit loses power, resets and releases the latch state, and the control module releases the CC wake-up self-closing state and enters the dormant state without the gun plugged in.

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