Excitation loss control system and control method for electric vehicle permanent magnet synchronous motor

Abstract

The invention relates to an excitation loss control system and control method for an electric vehicle permanent magnet synchronous motor, belonging to the technical field of motor control. The system comprises a motor status detecting module, an excitation loss judging module, an excitation loss control module, a vector control module, an IGBT (Insulated Gate Bipolar Translator) module and a space vector pulse width modulation module. In the method, the excitation loss judging module judges whether the motor loses excitation and the excitation loss degree according to the motor operating status and outputs the corresponding control signal to the vector control module according to the excitation loss degree; the vector control module generates current control quantity of the permanent magnet synchronous motor; and the space vector pulse width modulation module controls the IGBT module, so that the motor is controlled according to the excitation loss status of the permanent magnet synchronous motor, and the controllability of the motor after excitation loss and the vehicle safety are effectively improved. Moreover, the excitation loss control system and control method for the electric vehicle permanent magnet synchronous motor have the advantages that the system is simple in structure and low in cost, and the method is simple in application mode and extensive in application range.

Description

technical field [0001] The invention relates to the technical field of motors, in particular to the technical field of permanent magnet synchronous control, in particular to an electric vehicle permanent magnet synchronous motor demagnetization control system and control method. Background technique [0002] In recent years, with the rapid increase of car ownership worldwide, resource and environmental problems have become increasingly prominent. Because of the advantages of cleanliness, no pollution, high efficiency and diversified energy sources, electric vehicles have broad prospects for development. All countries are stepping up the research and development of electric vehicles. [0003] Permanent magnet synchronous motors have been widely used in the field of electric vehicles due to their advantages of high efficiency, high power density and structural diversity. Permanent magnets are an important part of permanent magnet synchronous motors. The permanent magnet fiel...

AI Technical Summary

Problems solved by technology

The permanent magnet field of the permanent magnet motor cannot be adjusted, and the motor adopts field-weakening control at high speed. Once the motor is in the high-speed field-weakening condition or a short-circuit fault occurs, a large demagnetization current will be generated, forming a strong demagnetization magnetic field, so that The permanent magnet is at a lower working point, and there is a risk of demagnetization; the thermal stability, uniformity and consistency of the permanent magnet material itself also affect the anti-demagnetization ability of the permanent magnet; when subjected to severe mechanical vibration, the permanent magnet also demagnetization will occur

When the permanent magnet loses its magnetism, the performance indicators of the motor will change, resulting in an increase in the motor current and temperature, affecting the insulation performance of the motor and the reliability of the controller, resulting in system instability, uncontrollable motor, and even damage to the motor. Serious hazard to vehicle safety

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