Cold backup control system and method for vehicle chassis controller

Abstract

The present invention provides a vehicle chassis controller and cold backup control system and method, comprising a main control system, a backup control system, and a backup switching circuit. The main control system includes a main controller MCU1 and a main power supply chip SBC connected to MCU1; the backup control system includes a backup controller MCU2 and a backup power supply connected to MCU2. A power supply Vin is connected to the SBC of the main control system and the backup switching circuit, respectively. The backup switching circuit is capable of automatically switching the main control system to the backup control system. The control system and method of the present invention ensure that the main control system automatically switches to the backup control system in a timely manner when an abnormality occurs, and also prevent the backup control system from being accidentally activated during a reset of the main control system. Furthermore, the independently operating backup switching circuit is simple and practical, making it particularly suitable for reliable control of vehicle chassis control systems.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle electronic control, and in particular to a cold backup control system and method for a vehicle chassis controller. Background Art

[0002] The safety performance of a vehicle's chassis is crucial to vehicle safety, placing extremely high demands on its functional reliability. This is especially true for new energy vehicles, such as autonomous vehicles. If a serious malfunction occurs in the chassis control system during autonomous driving, system safety requires that the control system recover quickly and ensure that the vehicle remains drivable during the malfunction.

[0003] However, the currently commonly used multi-core MCU controller solution can only handle faults within the MCU itself, and cannot block faults outside the MCU. Although the use of redundant solutions such as hot backup can improve the reliability of the system, it cannot eliminate the hidden dangers of simultaneous failure of both systems. Therefore, under complex environmental conditions, a cold backup control system is required to enable the vehicle chassis controller system to switch from a fault to another mode, ensuring that the vehicle can be safely taken over and transitioned before the serious fault is eliminated. For example, the Chinese patent CN201811324479.9 discloses a dual-redundant UAV brake controller and a cold backup control method. However, it is a cold backup system specifically used for braking on aircraft, and does not take into account the situation where the MCU and its power supply module suddenly fail. It also requires the use of a monitoring arbitration unit that is always working to collect multiple status signals sent by the MCU and cache the current PWM signal duty cycle instructions. In addition, it cannot complete the automatic switching between the primary and backup systems when an abnormality occurs in the monitoring arbitration unit.

[0004] Therefore, it is necessary to design a special cold backup for the signal and control system of the vehicle chassis controller to further improve the reliability of the chassis controller in complex and harsh environments. Summary of the Invention

[0005] (1) Technical issues to be resolved

[0006] The present invention provides a cold backup control system and method for a vehicle chassis controller. By collecting key system signals, the system can ensure that the main control system automatically switches to the backup control system in a timely manner when an abnormality occurs, and can also prevent the backup control system from being mistakenly activated when the main control system is reset. The independently working backup switching circuit is simple and practical, and is particularly suitable for reliable control of the vehicle chassis control system. In addition, the backup control system can monitor and analyze the status of the main control system circuit through its own monitoring circuit and control method when a serious fault occurs in the main control circuit, so as to determine the fault type and potential risks.

[0007] (2) Technical solution

[0008] The present invention provides a cold backup control system for a vehicle chassis controller, which is characterized by comprising a main control system, a backup control system and a backup switching circuit, wherein the main control system comprises a main controller MCU1 and a main power chip SBC connected to MCU1, the backup control system comprises a backup controller MCU2 and a backup power supply connected to MCU2, a power supply Vin is connected to the SBC of the main control system and the backup switching circuit respectively, and the backup switching circuit can automatically control the main control system to switch to the backup control system; the backup switching circuit comprises resistors R1-R4, a capacitor C1, an NMOS transistor Q1 and PMOS tube Q2 and PMOS tube Q3, the DIS1 signal output by the MCU1 is connected to one end of R1, the other end of R1 is connected to the gate of Q1 and one end of C1, the other end of C1 is connected to the source of Q1 and then grounded, the drain of Q1 is respectively connected to the gate of Q2 and one end of R2, the drain of Q2 is respectively connected to one end of R3, one end of R4 and the gate of Q3, the other end of R4 is grounded, the power supply Vin is respectively connected to the other end of R2, the source of Q2, the other end of R3 and the source of Q3, and the drain of Q3 is connected to the power supply end of the backup power supply.

[0009] Preferably, R1 and C1 form a delay circuit, and the delay time of the delay circuit is set to be greater than the reset time of the main controller MCU1.

[0010] Preferably, it further comprises a monitoring circuit connected to the MCU2, and the monitoring circuit is connected to the MCU1 and the SBC respectively to monitor the fault state after the main control system fails.

[0011] Preferably, it also includes a resistor R5, an NMOS tube Q4 and a resistor R6, the DIS2 signal of the main controller MCU1 is connected to one end of R5, the other end of R5 is connected to the gate of Q4, the source of Q4 is grounded, the drain of Q4 is connected to the power supply enable terminal EN of the backup power supply, the power supply Vin is connected to the power supply end of the backup power supply, and is respectively connected to the power supply enable terminal EN of the DC / DC power supply and the drain of Q4 through the R6.

[0012] Preferably, the backup power supply is specifically a DC / DC power supply, and the power supply Vin is specifically connected to the SBC and the backup switching circuit in the main control system respectively through a protection circuit.

[0013] Preferably, it also includes a CAN transceiver 1 and a CAN transceiver 2, the main power chip SBC powers MCU1 and CAN transceiver 1, the backup power supply powers MCU2 and CAN transceiver 2, the MCU1 is bidirectionally connected to the CAN transceiver 1, the MCU2 is bidirectionally connected to the CAN transceiver 2, and the CAN transceiver 1 and CAN transceiver 2 are respectively connected to the CAN bus for communication.

[0014] In another aspect, the present invention further discloses a control method for the cold backup control system of the vehicle chassis controller as described above, wherein the control method for MCU1 in the main control system includes:

[0015] Step A: When the main control system is working normally, both DIS1 and DIS2 signals are set to 1;

[0016] Step B: Report the current working status of the main control system through real-time communication with the CAN bus.

[0017] Preferably, after the main control system fails, the backup control system will establish a periodic task with a preset time to monitor the status of the SBC and MCU1 of the main control system. The control method of MCU2 in the backup control system includes:

[0018] Step 1: Back up the control system and initialize the system parameters. The status flags ST1 and ST2 are set to 1 by default.

[0019] Step 2: The backup control system works and determines whether the preset time has been exceeded. If so, proceed to step 3; if not, continue to step 2.

[0020] Step 3: Determine whether the status flag ST1 or ST2 is 1. If so, proceed to step 4. If not, end the control method.

[0021] Step 4: Determine whether the SBC power supply of the main control system is normal. If so, proceed to the next step 5. If not, set ST1 to 0, set ST2 to 0, and report the current main control system fault 1 through the CAN bus, that is, both the SBC and MCU1 are faulty, and jump to step 2;

[0022] Step 5: Determine whether the MCU1 status of the main control system is normal. If so, execute the next step 6. If not, set ST1 to 1 and ST2 to 0, and report the current main control system fault 2 through the CAN bus, that is, the MCU1 is faulty and the SBC is normal, and jump to step 2;

[0023] Step 6: Reset the main control system, and set the status flags ST1 and ST2 to 1 to start the next cycle.

[0024] Preferably, resetting the main control system in step 6 specifically includes resetting the main controller MCU1, and the preset time is 100ms.

[0025] In another aspect, the present invention further discloses a vehicle, comprising a cold backup control system of the vehicle chassis controller described in any one of the above.

[0026] (3) Beneficial effects

[0027] The cold backup control system and control method of the vehicle chassis controller of the present invention have the following advantages:

[0028] 1) The main control system and backup control system of the present invention are independent of each other, not only in terms of power supply but also in terms of input signal acquisition and output control. This eliminates coupling circuits between the main and backup systems. The backup control system is not a copy of the main control system. To maintain cost and system risk control, the cold backup system only acquires critical system signals and controls safety-critical functions, thus acting as a derated control system for the main control system. When the main control system is operating, the backup control system is powered off. During this time, the main control system's signal acquisition, communication, and output control are independent of the backup control system, rendering the backup system isolated. When the main control system fails, the backup control system is triggered, and the controller enters backup system operation mode. Furthermore, the main control system automatically switches to the backup control system. In the event of an unrecoverable failure in the main control system, when MCU1 loses control, the backup controller switches to the backup control system. This process requires no system instructions or intervention and is implemented by the hardware circuitry within the backup switching control system. Furthermore, DIS2 and Q4 are redundantly configured to disable the backup power supply of the backup system.

[0029] 2) The present invention eliminates the need for a monitoring arbitration unit that must always be powered and collects complex status signals to complete active master-slave switching. By designing a cold backup control system for a vehicle chassis controller with a backup switching circuit, the backup switching circuit is isolated from the primary and backup systems, enabling the following multiple functions to be independently implemented: a) When MCU1 is normally powered and DIS1 outputs a high level, a delay is implemented to avoid erroneous activation of the backup system (a delay circuit composed of R1 and C1 is set to a delay time greater than the reset time of MCU1), and the DC / DC backup power supply is cut off to prevent erroneous activation of the backup control system when the MCU1 in the primary control system is reset; b) When MCU1 is abnormal and the DIS1 output is 0, the DC / DC backup power supply is normally powered without delay, achieving the purpose of timely switching to the backup power supply. The overall circuit structure is streamlined and reliable, integrating functions such as delay, power supply, and cold backup switching control. It controls the activation of the cold backup function offline by collecting key system signals, making it particularly suitable for reliability control of vehicle chassis controllers.

[0030] 3) Furthermore, the control method of the present invention effectively monitors the status flags ST1 and ST2 of the SBC and MCU1, enabling the backup control system to monitor and reset the main control system circuitry through its own monitoring circuitry in the event of a serious fault in the main control circuitry. This enables monitoring of the power supply module SBC and MCU in the main control system to analyze the main control system's fault type and potential risks. In the event of a main control system failure, after the backup system is activated, the backup control system uses an independent CAN channel to report the failure, preventing the backend from misjudging the vehicle's current status. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 It is a circuit diagram of the cold backup control system of the vehicle chassis controller of the present invention;

[0033] Figure 2 This is a diagram of the power supply and communication structure of the cold backup control system of the vehicle chassis controller of the present invention;

[0034] Figure 3 This is a flow chart of the control method of the main control system in the present invention;

[0035] Figure 4It is a flow chart of the control method of the backup control system in the present invention. DETAILED DESCRIPTION

[0036] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0037] To address the safety and reliability issues of a vehicle chassis electronic control system, the controller of the present invention utilizes a cold backup system design. The backup control system is an independent hardware and software platform. Under normal operating conditions, the main control system is in a dominant position, and the backup system is disabled. At this time, the controller's power consumption is only equal to that of the main control system. However, because the main controller MCU (microcontroller) and the main power chip SBC (system basis chip, which can provide power supply, bus transceiver functions, diagnostic monitoring functions, and wake-up management functions) of the vehicle chassis main control system may both experience serious faults such as sudden power outages, it is impossible to ensure that a fault signal is sent promptly to complete the backup control system switch. Therefore, it is necessary to consider both preventing the backup control system from being accidentally activated when the main control system is normally powered and being able to promptly switch back to the main control system to resume normal operation after the fault is corrected. Therefore, it is necessary to design a cold backup control system for a vehicle chassis controller that meets both of these requirements.

[0038] See also Figure 1As shown, the present invention designs a cold backup control system for a vehicle chassis controller, comprising a main control system (also referred to as the main control system), a backup control system (also referred to as the backup system), and a backup switching circuit. The main control system includes a main controller MCU1 and a main power chip SBC, while the backup control system includes a backup controller MCU2 and a backup power supply. The main power chip SBC and the backup power supply respectively power the main controller MCU1 and the backup controller MCU2, serving as independent internal power supplies. Input power Vin is connected to the main control system SBC and the backup switching circuit. The backup switching circuit is used to automatically control the main control system to switch to the backup control system. The backup switching circuit specifically includes resistors R1-R4, capacitor C1, NMOS transistor Q1, PMOS transistor Q2 and PMOS transistor Q3. The DIS1 signal output by the main controller MCU1 is connected to one end of R1, the other end of R1 is connected to the gate of Q1 and one end of C1, the other end of C1 is connected to the source of Q1 and then to ground, the drain of Q1 is respectively connected to the gate of Q2 and one end of R2, the drain of Q2 is respectively connected to one end of R3, one end of R4 and the gate of Q3, the other end of R4 is grounded, the power supply Vin is respectively connected to the other end of R2, the source of Q2, the other end of R3 and the source of Q3, and the drain of Q3 is connected to the power supply end of the backup power supply.

[0039] In summary, the automatic switching between the primary and backup control systems is primarily achieved through the backup switching circuit. When the primary control system is operating normally, the active signal DIS1 is set to 1, turning on NMOS transistor Q1 and grounding the common terminal of R2 and Q2. Because Q2 is a PMOS transistor, when the control G is low, the source S is high, and the power supply Vin satisfies the negative voltage conduction condition of Vgs, Q2 turns on. Once Q2 turns on, both the G and S terminals of PMOS transistor Q3 are set to the power supply voltage, eliminating the voltage difference between their G terminals. Consequently, Q3 turns off, disconnecting the backup system's main circuit power supply. Conversely, when a fault occurs, the output of DIS1 is 0 (including when MCU1 is powered off), turning off both Q1 and Q2 and turning on Q3. The power supply Vin directly supplies power to the backup power supply through Q3, activating MCU2 and entering cold backup mode. In addition, R1 and C1 form a delay circuit to prevent the backup system from being activated by mistake. The delay time of the delay circuit is set to be greater than the reset time of the main controller MCU1, thereby ensuring that the backup control system is not triggered by mistake when the main controller is reset.

[0040] It should be pointed out that in order to realize the function of "automatically activating the backup system when an abnormality occurs in the main control system, and avoiding accidental activation of the backup control system when the main control system is powered normally; and being able to switch back from the backup control system to the main control system in time to resume normal operation after troubleshooting", the present invention first improves the output method of the system's key signals, so that the DIS1 signal emitted by the main controller MCU1 during normal operation is a high-level control signal 1. When an abnormality occurs, MCU1 may stop working and cannot emit a signal. At this time, the output DIS1 signal is a low-level signal 0. The DIS1 signal cooperates with the uniquely designed backup switching circuit to control the backup control system to work, thereby ultimately realizing the above functions.

[0041] In addition, the various resistors, MOS transistors and other devices in the backup switching circuit of the present invention are all necessary. For example, R1 and R2 are used to form a delay circuit and form a negative voltage difference of Vgs of Q2, and the functions of R3 and R4 are as follows: 1. When Q1 is not controlled by DIS1 and is turned off, the power supply voltage is divided by R3 and R4, and the voltage difference between the GS of Q3 is greater than the turn-on threshold, Q3 is turned on, and thus the power supply is connected through Q3; 2. When Q1 is controlled by DIS1 and turned on, it causes Q2 to be turned on. After Q2 is turned on, the power supply voltage passes through the S and D poles of Q2; therefore, the voltage drop of R3 is approximately 0, so that the G and S poles of the PMOS transistor Q3 are both set to the power supply voltage, there is approximately no voltage difference between the GS, and the GS of the Q3 tube is approximately turned on. Therefore, the Q3 tube is closed, cutting off the power supply to the backup power supply DC / DC.

[0042] In another embodiment, the backup power supply can be preferably a DC / DC power supply (i.e., a variable DC voltage source) for controlling the derating of the vehicle chassis controller. Furthermore, the input power supply Vin can be connected to the SBC and backup switching circuit in the main control system through a protection circuit to protect the power supply circuit or the entire device circuit.

[0043] In addition, although MCU1 and MCU2 work alternately, in order to realize the signal isolation input and output function of MCU1 and MCU2, the input signal input is input into MCU1 and MCU2 respectively from two pins through the input module, and the output signal output is received from the output signal of MCU1 and MCU2 respectively through the two pins of the output module, so that the signals of the main and standby systems are independent of each other.

[0044] In another embodiment, see Figure 2As can be seen, to achieve mutual independence between the primary and backup control systems, each uses its own channel for input / output signals. Preferably, the CAN buses of the primary and backup systems each utilize independent transceivers, namely, CAN transceiver 1 and CAN transceiver 2, respectively, to facilitate communication between the primary and backup systems and the CAN bus. The transceiver power supply modules serve as their own power supply modules. Specifically, the primary power supply chip (SBC) powers MCU1 and CAN transceiver 1, while the DC / DC power supply powers MCU2 and CAN transceiver 2. MCU1 and CAN transceiver 1 are connected in a bidirectional communication manner, while MCU2 and CAN transceiver 2 are connected in a bidirectional communication manner. CAN transceiver 1 and CAN transceiver 2 are each connected to the CAN bus.

[0045] In another embodiment, from a redundancy perspective, the present invention can also additionally disable the backup system's main DC / DC power supply. The main controller MCU1 also simultaneously outputs a signal DIS2 identical to DIS1 (which can also be directly controlled by the DIS1 signal), thereby redundantly controlling the backup system's DC / DC power supply. Specifically, the main controller MCU1's DIS2 signal is connected to one end of resistor R5, the other end of which is connected to the gate of an NMOS transistor Q4. The source of Q4 is grounded, and the drain of Q4 is connected to the power enable terminal EN of the DC / DC power supply. The input power supply Vin is connected to the power supply terminal of the DC / DC power supply and, through resistor R6, is connected to the power enable terminal EN of the DC / DC power supply and the drain of Q4. Therefore, Q4 is controlled by the DIS2 signal. When DIS2 is set to 1, the NMOS transistor Q4 is turned on, grounding the power enable terminal EN of the DC / DC power supply, thereby disabling the backup system's DC / DC power supply. When DIS2 is 0, Q4 is turned off, and the input power 2 separated from the power supply Vin sets the power supply enable terminal EN of the DC / DC to 1 through R6, redundantly ensuring the normal operation of the DC / DC power supply to improve reliability.

[0046] The main control system controls the power supply to the backup system through a backup switching circuit. After power is applied, DIS1 and DIS2 are set to 1. To reduce hardware costs, the backup system is a derated control system. The backup control system can monitor the fault status of the main control system after failure through a monitoring circuit connected to MCU2. The monitoring circuit is connected to MCU1 and SBC respectively. When the main control system's SBC and MCU1 are both in normal status, the corresponding flag bits (ST1, ST2) are set to 1, attempting to reset the main control system and switching from the backup control system to the main control system to control the vehicle chassis.

[0047] Also, see Figure 3 As shown, the control method of MCU1 in the main control system includes:

[0048] Step A: When the main control system is working normally, both DIS1 and DIS2 signals are set to 1;

[0049] Step B: Report the current working status of the main control system through real-time communication with the CAN bus.

[0050] After the master control system fails, the backup system establishes a 100ms periodic task to monitor the status of the master control system's SBC and MCU1. It also assigns values ​​to the SBC and MCU1 states, ST1 and ST2, respectively. ST1 corresponds to the SBC state, and ST2 corresponds to the MCU1 state. By default, after the backup system starts up and initializes system parameters, the initial values ​​of the status flags ST1 and ST2 are set to 1. If the backup system detects that both the SBC and MCU1 are faulty, it sets ST1 and ST2 to 0, thereby exiting monitoring of the master control system. During the monitoring process, the master control system's fault type is reported via the CAN bus for backend decision-making.

[0051] See also Figure 4 As shown in the figure, after the main control system fails, the backup control system will establish a 100ms periodic task to monitor the status of the SBC and MCU1 of the main control system. The control method of MCU2 in the backup system specifically includes:

[0052] Step 1: Back up the control system and initialize the system parameters. The status flags ST1 and ST2 are set to 1 by default.

[0053] Step 2: The backup control system works and determines whether the periodic task time exceeds 100ms. If so, proceed to step 3. If not, continue to step 2.

[0054] Step 3: Determine whether the status flag ST1 or ST2 is 1. If so, proceed to step 4. If not, end the control method.

[0055] Step 4: Determine whether the SBC power supply of the main control system is normal. If so, proceed to the next step 5. If not, set ST1 to 0, set ST2 to 0, and report the current main control system fault 1 through the CAN bus, that is, both the SBC and MCU1 are faulty, and jump to step 2;

[0056] Step 5: Determine whether the MCU1 status of the main control system is normal. If so, execute the next step 6. If not, set ST1 to 1 and ST2 to 0, and report the current main control system fault 2 through the CAN bus, that is, the MCU1 is faulty and the SBC is normal, and jump to step 2;

[0057] Step 6: Reset the main control system (including resetting MCU1), and set the status flags ST1 and ST2 to 1 to start the next cycle.

[0058] As can be seen from the above control method, when the control system is in the backup system working mode, the backup control system monitors the fault status of the main power chip SBC (System Basis Chip) and MCU1 of the main control system. If the SBC status signal (ST1) of the main control system is normal, the backup system will then determine the MCU1 status (ST2) of the main control system; if the SBC power supply of the main control system is abnormal, there is no need to determine the status of MCU1, and ST1 and ST2 are set to 0; at the same time, the fault is reported through the CAN bus; if the SBC status is normal and the MCU1 status is also normal, the backup system will attempt to reset the main control system and set ST1 and ST2 to 1 to facilitate the next (100M cycle) status monitoring of the main control system. Therefore, through the flags ST1 and ST2 and the monitoring circuit, the backup control system of the present invention can quickly and effectively confirm the fault type of the main control system and restore the main control system to work in time after the fault is eliminated. After the main control system starts working, it will send a DIS1 signal to disable the backup system for cold backup work.

[0059] In another aspect, the present invention further claims protection for a vehicle equipped with the cold backup control system of the vehicle chassis controller. Preferably, the vehicle is a new energy vehicle that can be equipped with an unmanned driving function.

[0060] Compared with the prior art, the advantages of the present invention are as follows:

[0061] 1. To achieve controller reliability, the main control system and the backup control system work alternately. When the main control system MCU1 loses control function, it automatically switches to the backup control system and is not affected by the main control system circuit, thus ensuring system reliability;

[0062] 2. The relationship between the main control system and the backup system is as follows: during normal operation, the main control system works and the backup system is powered off; when the main control system is abnormal, the backup system takes over the control task, and the backup system is in derated control mode, controlling only the signals and drive signals that affect functional safety;

[0063] 3. Fault reporting function: when the main control system fails, the backup control system will take over and automatically identify and judge the fault of the main control system and report it, which is conducive to the background to make correct decisions.

[0064] 4. The backup control system's derating control functions collect and control key signals that affect safety. This not only reduces hardware costs but also ensures vehicle safety control.

[0065] 5. The backup switching control system switches and activates the cold backup through the main control system's control of the MOS tube on and off. When the main control system is working, the circuit that supplies power to the backup system will be in a closed state; only when the main control system MCU1 loses its control function can the backup system be powered and work.

[0066] 6. When the backup system is working, it monitors the SBC power supply and MCU1 status of the main control system. After confirming the failure of both, it takes over the emergency task and enters the safe mode. After confirming that both are restored, it quickly switches back to the normal working mode of the main control system and automatically exits the cold backup working mode.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A cold backup control system for a vehicle chassis controller, characterized in that: The system includes a main control system, a backup control system, and a backup switching circuit. The main control system includes a main controller MCU1 and a main power chip SBC connected to MCU1. The backup control system includes a backup controller MCU2 and a backup power supply connected to MCU2. The power supply Vin is connected to the SBC of the main control system and the backup switching circuit respectively. The backup switching circuit can automatically control the main control system to switch to the backup control system. The backup switching circuit includes resistors R1-R4, capacitor C1, NMOS transistor Q1, PMOS transistor Q2, and PMOS transistor Q3. , the DIS1 signal output by the MCU1 is connected to one end of R1, the other end of the R1 is connected to the gate of Q1 and one end of C1, the other end of the C1 is connected to the source of Q1 and then grounded, the drain of Q1 is respectively connected to the gate of Q2 and one end of R2, the drain of Q2 is respectively connected to one end of R3, one end of R4 and the gate of Q3, the other end of R4 is grounded, the power supply Vin is respectively connected to the other end of R2, the source of Q2, the other end of R3 and the source of Q3, and the drain of Q3 is connected to the power supply end of the backup power supply; The system also includes a resistor R5, an NMOS tube Q4 and a resistor R6. The DIS2 signal of the main controller MCU1 is connected to one end of R5, the other end of R5 is connected to the gate of Q4, the source of Q4 is grounded, the drain of Q4 is connected to the power enable terminal EN of the backup power supply, the power supply Vin is connected to the power supply end of the backup power supply, and is respectively connected to the power enable terminal EN of the DC / DC power supply and the drain of Q4 through R6.

2. The cold backup control system of the vehicle chassis controller according to claim 1, characterized in that: The R1 and C1 form a delay circuit, and the delay time of the delay circuit is set to be greater than the reset time of the main controller MCU1.

3. The cold backup control system of the vehicle chassis controller according to claim 2, characterized in that: It also includes a monitoring circuit connected to the MCU2, and the monitoring circuit is connected to the MCU1 and the SBC respectively to monitor the fault state after the main control system fails.

4. The cold backup control system of the vehicle chassis controller according to any one of claims 1 to 3, characterized in that: The backup power supply is specifically a DC / DC power supply, and the power supply Vin is specifically connected to the SBC and the backup switching circuit in the main control system respectively through a protection circuit.

5. The cold backup control system of the vehicle chassis controller according to any one of claims 1 to 3, characterized in that: It also includes CAN transceiver 1 and CAN transceiver 2. The main power supply chip SBC powers MCU1 and CAN transceiver 1, and the backup power supply powers MCU2 and CAN transceiver 2. The MCU1 is connected to the CAN transceiver 1 for bidirectional communication, and the MCU2 is connected to the CAN transceiver 2 for bidirectional communication. The CAN transceiver 1 and CAN transceiver 2 are respectively connected to the CAN bus for communication.

6. A control method for a cold backup control system of a vehicle chassis controller according to any one of claims 1 to 5, characterized in that: The control method of MCU1 in the main control system includes: Step A: When the main control system is working normally, both DIS1 and DIS2 signals are set to 1; Step B: Report the current working status of the main control system through real-time communication with the CAN bus.

7. The control method according to claim 6, characterized in that: After the main control system fails, the backup control system will establish a periodic task with a preset time to monitor the status of the SBC and MCU1 of the main control system. The control method of MCU2 in the backup control system includes: Step 1: Back up the control system and initialize the system parameters. The status flags ST1 and ST2 are set to 1 by default. Step 2: The backup control system works and determines whether the preset time has been exceeded. If so, proceed to step 3; if not, continue to step 2. Step 3: Determine whether the status flag ST1 or ST2 is 1. If so, proceed to step 4. If not, end the control method. Step 4: Determine whether the SBC power supply of the main control system is normal. If so, proceed to the next step 5. If not, set ST1 to 0, set ST2 to 0, and report the current main control system fault 1 through the CAN bus, that is, both the SBC and MCU1 are faulty, and jump to step 2; Step 5: Determine whether the MCU1 status of the main control system is normal. If so, execute the next step 6. If not, set ST1 to 1 and ST2 to 0, and report the current main control system fault 2 through the CAN bus, that is, the MCU1 is faulty and the SBC is normal, and jump to step 2; Step 6: Reset the main control system, and set the status flags ST1 and ST2 to 1 to start the next cycle.

8. The control method according to claim 7, characterized in that: Resetting the main control system in step 6 specifically includes resetting the main controller MCU1, and the preset time is 100ms.

9. A vehicle, characterized in that: The vehicle includes a cold backup control system of the vehicle chassis controller according to any one of claims 1-5.

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