Electric automobile limping control system and automobile

Abstract

The utility model discloses a limping control system of an electric automobile. The limping control system comprises a whole automobile controller, a limping control unit, a power battery BMS and a battery high-voltage cabinet. The vehicle control unit outputs control signals to a limp control unit, a power battery BMS and a motor controller MCU after entering a limp mode, a driving system of a high-voltage electric appliance outside a motor is arranged in a battery high-voltage cabinet, and the power supply end of the driving system is connected to a storage battery through a relay K; the limp control unit is connected to a relay K through a control circuit; the power battery BMS is used for limiting the power output and the power supply output electric quantity of the power battery according to the limp mode control signal of the whole vehicle controller, and the motor controller MCU is used for limiting the rotating speed of the motor according to the limp mode control signal of the whole vehicle controller. The limping control is realized through a simple circuit, the limping distance can be customized by a user, and the user experience of limping is improved.

Description

Technical Field

[0001] The utility model relates to the field of new energy vehicle fault control, in particular to an electric vehicle limp home control system and an automobile. Background Art

[0002] After a vehicle electronic component fails, in order to enable the vehicle to travel within a safe range for a period of time to facilitate the user to reach a repair point and avoid breaking down midway. In the field of fuel vehicles, there are relatively mature limp home control solutions. However, with the continuous increase of oil prices and the aggravation of environmental pollution, new energy vehicles that are energy-saving and environmentally friendly have begun to be taken seriously by people. In particular, deep hybrid vehicles have developed rapidly. More and more fuel vehicles are being replaced by electric vehicles. Electric vehicles have added electrical equipment such as motors, batteries, and controllers compared with traditional vehicles. Such equipment is in the development stage in vehicle applications and has a high failure rate. Therefore, it is necessary to add a limp home mode. For example, a limp home control method and system based on an electric vehicle distributed drive system with a patent application number of 201710014098.X discloses that when a single drive motor fails, based on the electronic differential system and equipped sensors necessary for in-wheel (wheel-end) drive operation, the output power of the drive motor is controlled to ensure the running stability of the vehicle and the limp home function can be realized.

[0003] In the limp home modes of existing electric vehicles, most of them are relatively complex, ignoring the most basic requirements of limp home, which are to continue driving a short distance and the user experience in the limp home mode. The distance and time of limp home cannot be controlled and adjusted. Summary of the Utility Model

[0004] The purpose of the utility model is to overcome the deficiencies of the prior art and provide an electric vehicle limp home control system and an automobile, which realize the control of limp home through a simple circuit and can customize the limp home distance for users, improving the user experience of limp home.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] An electric vehicle limp home control system includes a vehicle controller, a limp home control unit, a power battery BMS, and a battery high-voltage cabinet; after entering the limp home mode, the vehicle controller respectively outputs control signals to the limp home control unit, the power battery BMS, and the motor controller MCU. A drive system for high-voltage electrical appliances other than the motor is provided in the battery high-voltage cabinet, and the power supply end of the drive system is connected to the storage battery through a relay K; the limp home control unit is connected to the relay K through a control circuit; the power battery BMS is used to limit the power output and power supply output power of the power battery according to the limp home mode control signal of the vehicle controller, and the motor controller MCU is used to limit the motor speed according to the limp home mode control signal of the vehicle controller.

[0007] The output end of the limp control unit is connected to the vehicle headlight system, and is used to drive and control the headlight system to turn on and off the hazard lights.

[0008] When the electric vehicle is a hybrid vehicle, the vehicle controller outputs a limp control signal to the power battery BMS. The BMS controls the vehicle to cut off the high voltage. At the same time, the output end of the vehicle controller is connected to the engine power system to start the engine power system to provide limp driving force.

[0009] The vehicle controller is connected to the limp distance and speed setting module. The limp distance and speed setting module inputs the limited limp distance and speed limit value in the limp mode to the vehicle controller; the vehicle controller acquires the distance and speed after the start of limp through the CAN network; the output end of the vehicle controller is connected to the limp reminder module, and the limp information is sent through the limp reminder module.

[0010] The limp reminder module is an in-vehicle multimedia system.

[0011] The limp distance and speed setting module includes a user's mobile phone or an in-vehicle touch screen.

[0012] The control circuit includes a voltage regulator, capacitors C1, C2 and a diode D1; the voltage regulator is a three-terminal voltage regulator. The driving voltage output by the limp control unit is respectively connected to the input end of the three-terminal voltage regulator; the grounding end of the three-terminal voltage regulator is connected to the negative output of the limp control unit; the input end of the three-terminal voltage regulator is connected to the output end of the three-terminal voltage regulator through capacitors C1 and C2. The grounding end of the three-terminal voltage regulator is connected between capacitors C1 and C2; the output end of the three-terminal voltage regulator is connected to the input end of the three-terminal voltage regulator through a diode D1; the output end of the three-terminal voltage regulator is connected to one end of the relay K coil, and the other end of the relay K coil is connected to the negative output of the limp control unit.

[0013] The three-terminal voltage regulator is LM7812T.

[0014] An electric vehicle, which includes the above-mentioned electric vehicle limp control system.

[0015] The advantages of the present invention are as follows: The limp control is realized through a simple circuit, and the limp distance can be user-defined, improving the user experience of limp; the hardware structure involved in the waveform control is simple, with low cost and easy implementation. It can disconnect the operation of the electric vehicle in time according to the fault type; when in the limp state, the power battery system can be kept working; after the limp mode, the user can customize the limp distance, improving the user experience of the limp mode and reducing safety risks; for hybrid vehicles, the engine limp is preferred to provide limp driving force to improve safety. Description of the Drawings

[0016] Brief descriptions are given below to the content expressed in the drawings of the specification of the present invention and the marks in the drawings:

[0017] Figure 1 It is the structural schematic diagram of the limp-home control system of the present utility model;

[0018] Figure 2 It is the circuit schematic diagram of the limp-home control system of the present utility model. Detailed implementation manners

[0019] The detailed implementation manners of the present invention are further described below by describing the optimal embodiments with reference to the drawings.

[0020] The most basic requirement for limp-home is to be able to continue driving for a certain distance after a vehicle failure, and then only be able to drive while other functions are prohibited. The existing limp-home solutions are all too complex, costly to implement, and the distance that can be driven in limp-home and the speed limit cannot be adjusted, resulting in a poor user experience. Therefore, the main purpose of this solution is to use a simple solution to achieve limp-home control, to disconnect the power supply of non-essential components after entering the limp-home mode in case of a failure, and at the same time provide adjustable speed limit and distance limit in the limp-home mode. The specific solution is as follows:

[0021] As Figure 1 shown, a limp-home control system for an electric vehicle in this solution includes a vehicle controller, a limp-home control unit, a power battery BMS, a battery high-voltage cabinet, and an MCU; after entering the limp-home mode, the vehicle controller outputs control signals to the limp-home control unit, the power battery BMS, and the motor controller MCU respectively. The vehicle controller VCU judges whether to enter the limp-home mode after receiving a vehicle failure signal. If it enters the limp-home mode, it sends control signals corresponding to the limp-home mode to the limp-home control unit, the power battery BMS, and the motor controller MCU respectively to execute the limp-home control instructions, and respectively realizes the power-off of non-essential high-voltage electrical appliances, the battery output power limitation, the motor speed limitation, etc. Specifically:

[0022] There is a drive system for high-voltage electrical appliances other than the motor inside the battery high-voltage cabinet. The power supply end of the drive system is connected to the battery through relay K; the limp-home control unit is connected to relay K through a control circuit; the drive system mainly drives and controls the high-voltage electrical appliances to work. For example, the drive systems for high-voltage electrical appliances such as air conditioners and PTC heaters are all set inside the battery high-voltage cabinet. These drive systems can control the startup of high-voltage electrical appliances when they work; these drive systems need to provide 24V power supply for their operation. Under normal conditions, the limp-home control unit drives relay K to close, and the drive systems all work normally, and can drive and control high-voltage electrical appliances such as air conditioners according to the actual vehicle control system; when in the limp-home mode, these drive systems need to be prohibited from working, and the corresponding high-voltage electrical appliances are turned off. Therefore, at this time, the switch of relay K is disconnected through drive control, and the drive systems are all powered off, and the high-voltage electrical appliances cannot be driven to work, thus achieving the purpose of turning off high-voltage electrical appliances other than the motor and only retaining power to achieve short-distance limp-home.

[0023] In order to limit power and speed during limp-home, the limp-home instruction output by the vehicle controller is sent to the BMS and the motor MCU; the BSM and MCU receive the signals and perform corresponding operations: the power battery BMS is used to limit the power output and power supply output power of the power battery according to the limp-home mode control signal of the vehicle controller, and the motor controller MCU is used to limit the motor speed according to the limp-home mode control signal of the vehicle controller, so as to meet the purpose of speed limit and other requirements in the limp-home state.

[0024] In order to further improve the safety during the limp-home mode, the output end of the limp-home control unit is connected to the vehicle lighting system, which is used to drive and control the lighting system to turn on and off the hazard lights. After receiving the limp-home instruction sent by the vehicle controller VCU, the limp-home control unit ECU drives the hazard lights of the vehicle to turn on, reminding the vehicles in front and behind that the vehicle is in a fault state and improving the safety during limp-home.

[0025] Since existing electric vehicles are divided into pure electric and hybrid types, and the hybrid type accounts for a relatively large proportion, in order to be applicable to the limp-home of hybrid electric vehicles, when the electric vehicle is a hybrid vehicle, the vehicle controller outputs a limp-home control signal to the power battery BMS, and the BMS controls the high voltage of the whole vehicle. At the same time, the output end of the vehicle controller is connected to the engine power system, starting the engine power system to provide limp-home power and limiting the output power of the engine system to limit the vehicle speed. Since the safety of fuel power supply is higher than that of high-voltage electricity in the event of electrical failures and other faults, in the limp-home state, if it is a hybrid vehicle, the engine is preferentially selected to provide power while turning off the battery high voltage to improve the safety of limp-home.

[0026] In a preferred embodiment, the present solution provides a solution for self-setting limp-home speed. Since the prior art commonly uses the methods of limiting speed and travel distance during limp-home to control the limp-home speed and distance, the user experience is improved. Therefore, in this solution, the vehicle controller is connected to the limp-home distance and speed setting module, and the limp-home distance and speed setting module inputs the limited limp-home distance and speed limit value in the limp-home mode to the vehicle controller; the vehicle controller acquires the distance and speed after the start of limp-home through the CAN network; the output end of the vehicle controller is connected to the limp-home reminder module, and the limp-home information is sent through the limp-home reminder module. The limp-home reminder module is an in-vehicle multimedia, including an instrument, an audio-visual entertainment screen, etc.; the limp-home distance and speed setting module includes a user's mobile phone or an in-vehicle touch screen. The in-vehicle touch screen can be directly connected to the VCU through the CAN network for interaction, while the mobile phone app accesses the TBOX through the vehicle network and accesses the vehicle CAN network through the tBOX, and finally accesses the connection of the vehicle controller, so as to realize the input of setting parameters. The user can adjust the set speed limit value and the distance of limited limp-home travel according to their own needs.

[0027] In this solution, the limp-home control unit drives the relay through a control circuit, such as Figure 2 shown, the control circuit includes a voltage regulator, capacitors C1, C2 and a diode D1; the voltage regulator is a three-terminal voltage regulator, and the driving voltage output by the limp-home control unit is respectively applied to the input terminal of the three-terminal voltage regulator; the ground terminal of the three-terminal voltage regulator is connected to the negative output of the limp-home control unit; the input terminal of the three-terminal voltage regulator is connected to the output terminal of the three-terminal voltage regulator through capacitors C1 and C2, and the ground terminal of the three-terminal voltage regulator is connected between capacitors C1 and C2; the output terminal of the three-terminal voltage regulator is connected to one end of the relay K coil through the diode D1, and the other end of the relay K coil is connected to the negative output of the limp-home control unit. The three-terminal voltage regulator is LM7812T. The limp-home control unit can be implemented by adding a new in-vehicle ECU or reusing an existing in-vehicle ECU. The main switch S of the 24V battery is closed after the vehicle is powered on and disconnected after the power is off; in this solution, the battery is a 24V DC battery, the output voltage of the relay is 12V, the voltage regulator used is an LM7812T three-terminal voltage regulating integrated circuit, the capacitor C1 is 0.33 μF, and the capacitor C2 is 0.1 μ.

[0028] This embodiment also provides an electric vehicle, and the electric vehicle includes the electric vehicle limp-home control system in the above embodiment. Since this vehicle includes all the features of the limp-home control system, it also has the following advantages: simple circuit structure, high stability, when the vehicle encounters a fault, it can ensure that the vehicle can safely drive to the designated location, without causing roadblocks or being towed by a tow truck, and the cost is relatively low.

[0029] Obviously, the specific implementation of the present invention is not limited by the above-mentioned methods. As long as various non-substantive improvements are made by adopting the method concept and technical solution of the present invention, they are all within the protection scope of the present invention.

Claims

1. A limp home control system for an electric vehicle, characterized in that: It includes a vehicle controller, a limp home control unit, a power battery BMS, and a battery high-voltage cabinet; the vehicle controller outputs control signals to the limp home control unit, the power battery BMS, and the motor controller MCU respectively after entering the limp home mode; the battery high-voltage cabinet is provided with a drive system for high-voltage electrical appliances other than the motor, and the power supply end of the drive system is connected to the battery via a relay K; the limp home control unit is connected to the relay K through a control circuit; the power battery BMS is used to limit the power output and power supply output of the power battery according to the limp home mode control signal of the vehicle controller, and the motor controller MCU is used to limit the motor speed according to the limp home mode control signal of the vehicle controller.

2. The electric vehicle limp home control system according to claim 1, characterized in that: The output end of the limp home control unit is connected to the vehicle lighting system, and is used to drive and control the lighting system to light up or extinguish the double flash lights.

3. The electric vehicle limp home control system according to claim 1, characterized in that: When the electric vehicle is a hybrid vehicle, the vehicle controller outputs a limp-home control signal to the power battery BMS, and the BMS controls the vehicle to lower the high voltage. At the same time, the output end of the vehicle controller is connected to the engine power system, and the engine power system is started to provide limp-home power.

4. An electric vehicle limp home control system according to any one of claims 1 to 3, characterized in that: The vehicle controller and the limp distance and speed setting module, the limp distance and speed setting module inputs the limp distance and speed limit specified in the limp mode to the vehicle controller; the vehicle controller collects and obtains the distance and speed after the start of limpness through the CAN network; the output end of the vehicle controller is connected to the limp reminder module, and the limp information is sent out through the limp reminder module.

5. The limp home control system of an electric vehicle as claimed in claim 4, characterized in that: The limp reminder module is a vehicle-mounted multimedia.

6. The electric vehicle limp home control system according to claim 4, characterized in that: The limp distance and speed setting module includes a user's mobile phone or a vehicle-mounted touch screen.

7. An electric vehicle limp home control system according to any one of claims 1 to 3, characterized in that: The control circuit includes a voltage stabilizer, capacitors C1, C2 and a diode D1; the voltage stabilizer is a three-terminal voltage stabilizer, and the driving voltage output by the limp control unit is respectively connected to the input end of the three-terminal voltage stabilizer; the ground end of the three-terminal voltage stabilizer is connected to the negative output electrode of the limp control unit; the input end of the three-terminal voltage stabilizer is connected to the output end of the three-terminal voltage stabilizer via capacitors C1 and C2, and the ground end of the three-terminal voltage stabilizer is connected between capacitors C1 and C2; the output end of the three-terminal voltage stabilizer is connected to the input end of the three-terminal voltage stabilizer via a diode D1; the output end of the three-terminal voltage stabilizer is connected to one end of the relay K coil, and the other end of the relay K coil is connected to the negative output electrode of the limp control unit.

8. The electric vehicle limp home control system according to claim 7, characterized in that: The three-terminal voltage regulator is LM7812T.

9. An electric vehicle, characterized in that: The electric vehicle comprises the electric vehicle limp home control system as described in any one of claims 1-8.

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