Open-circuit fault diagnosis method for drive system of double-winding fault-tolerant permanent-magnet motor

Abstract

The invention discloses an open-circuit fault diagnosis method for the drive system of a double-winding fault-tolerant permanent-magnet motor. According to the method, the collected phase current of a motor is respectively subjected to the converting and processing process by a low-pass filter, a Clarke convertor, a Park vector processor, a normalization processor, an average value calculator, an absolute value calculator and an absolute value averaging processor, so as to obtain the average value of the normalized phase current of the motor and the average value of the absolute value of the normalized phase current of the motor. With the average value of the normalized phase current of the motor and the average value of the absolute value of the normalized phase current of the motor as a basis, fault diagnostic variables for the system are constructed, so that the open-circuit fault of the drive system of the double-winding fault-tolerant permanent-magnet motor can be detected and positioned in real time. Based on the above method, no extra current sensor is required, so that the method is simple, feasible and high in reliability. Based on the combined utilization of the average value of the normalized current and the average value of the absolute value of the normalized current, the incorrect diagnosis caused by load sudden change and other reasons during the conventional diagnosis process can be avoided. Meanwhile, the diagnosis time is greatly reduced. Therefore, the open-circuit fault of the drive system can be effectively detected and positioned in real time.

Description

technical field [0001] The invention relates to the field of reliability and fault diagnosis of a motor drive system, in particular to an open-circuit fault diagnosis method of a double-winding permanent magnet fault-tolerant motor drive system. Background technique [0002] With the development of multi-electric, all-electric aircraft and hybrid and pure electric vehicles, the motor drive system has ushered in new development opportunities and challenges. In addition to requiring high power density and high efficiency, it also needs to have high output performance and high reliability. performance, which has become the key to the motor drive system. In the 1990s, the emergence of permanent magnet fault-tolerant motor and its control system improved the safety and reliability of the system, and it has been applied to the aviation field. However, due to electromagnetic interference, insulation aging, poor contact and other reasons, some electrical faults often occur in the m...

AI Technical Summary

Problems solved by technology

In 1998, Professor A.J.Marques Cardoso proposed the current Park vector method for inverter fault diagnosis, but this method requires a very complicated pattern recognition algorithm and is not suitable for integration into the drive controller

Subsequently, the average current Park vector method was proposed. This method is carried out in the d-q coordinate system and can quickly judge and determine which IGBT is faulty.

In order to overcome these shortcomings, relevant scholars have proposed the normalized average current method, the normalized average current absolute value method, etc. These methods can improve the robustness of fault diagnosis to a certain extent, but the calculation is too complicated and still There is a potential problem of misjudgment due to sudden changes in load and speed

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