Trailer protection system for hybrid power and pure electric automobile

Abstract

The invention discloses a trailer protection system for a hybrid power and pure electric automobile. The trailer protection system comprises a diagnosis module and a main control module, wherein the diagnosis module outputs dragging state signals when the automobile is dragged, the main control module controls the starting of a direct current voltage transformer to enter a voltage drop type conversion when receiving the dragging state signals; in addition, if the voltage at the two ends of a bus capacitor of a motor inverter is smaller than the reference voltage, a permanent magnet synchronous motor is controlled to output the negative torque, if the voltage at the two ends of the bus capacitor of the motor inverter is greater than or equal to the reference voltage, the permanent magnet synchronous motor is controlled to output positive torque, and if the electric quantity of a low-voltage battery is greater than the set electric quantity threshold value, the direct current voltage converter is controlled to stop the charging on the low-voltage battery. The trailer protection system has the advantages that the damage risk of the motor inverter and the motor due to overcurrent and overvoltage can be avoided, meanwhile, excessive energy generated in the automobile dragging process can be utilized to the maximum degree, and in addition, the cost is low.

Description

technical field [0001] The invention relates to new energy vehicle technology, in particular to a trailer protection system for hybrid and pure electric vehicles. Background technique [0002] The simplified schematic diagram of the motor control system of hybrid power and pure electric vehicle is shown in Figure 1, and described motor control system comprises: [0003] The permanent magnet synchronous motor, whose mechanical output shaft is connected with the transmission system of hybrid and pure electric vehicles, outputs torque and power for hybrid and pure electric vehicles. When the permanent magnet synchronous motor is dragged by the transmission system of hybrid and pure electric vehicles at high speed When moving, it also generates three-phase alternating current at the three-phase alternating current port in turn; [0004] A high-voltage battery, usually with a voltage of several hundred volts or more, is used as the driving power of the permanent magnet synchrono...

AI Technical Summary

Problems solved by technology

However, this solution has certain limitations, and it is only suitable for such system components with small short-circuit current of the motor. For motors with large short-circuit current, especially when the continuous output capacity of the motor inverter or the motor is exceeded, if the active down Short-circuit strategy For long-term towing conditions, the motor inverter and motor will be damaged by overheating and overvoltage during the towing process, causing irreversible damage to the electric drive system, and the trailer resistance is too large, the vehicle shakes, and even High-voltage electric shock endangers personal safety

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