Turn-to-turn short-circuit current indirect measurement method for open-winding permanent magnet generator

Abstract

The invention discloses a turn-to-turn short-circuit current indirect measurement method for an open-winding permanent magnet generator, and the method comprises the steps: firstly actively expandingthe short-circuit ratio of a fault winding to 100% through actively controlling converter bridge arms at two ends of the fault winding; secondly, realizing high-precision instantaneous indirect measurement of turn-to-turn short-circuit current through an original current sensor of a fault winding; thirdly, constructing a mathematical model of the turn-to-turn short-circuit current according to themeasured instantaneous turn-to-turn short-circuit current; and finally, blocking converter bridge arms at two ends of the fault winding, and recovering the turn-to-turn short circuit ratio to the original state. A sensor does not need to be additionally arranged, the problem that turn-to-turn short-circuit current cannot be directly measured is avoided through a method of actively short-circuiting a motor fault winding, and the reliability and safety of a motor driving system are improved.

Description

technical field [0001] The invention relates to an indirect measurement method for inter-turn short-circuit current of an open-winding permanent magnet generator, belonging to the technical field of motor control. Background technique [0002] At present, most of the fault-tolerant control of multi-phase motors focuses on open-circuit faults, and there are relatively few studies on the fault-tolerant control of inter-turn short circuits. After the turn-to-turn short-circuit fault occurs, the rotating permanent magnet flux linkage will continue to induce back electromotive force in the short-circuited armature winding, thereby generating short-circuit current. Inter-turn short-circuit current will destroy the original circular rotating magnetic field, produce obvious torque fluctuation, and affect the operation reliability of the system. To carry out fault-tolerant control of the inter-turn short-circuit fault of the motor, it is necessary to measure the inter-turn short-cir...

AI Technical Summary

Problems solved by technology

Turn-to-turn short-circuit current will destroy the original circular rotating magnetic field, resulting in obvious torque fluctuations and affecting the operational reliability of the system

To carry out fault-tolerant control of the inter-turn short-circuit fault of the motor, it is necessary to measure the inter-turn short-circuit current. However, it is difficult to accurately determine the number of turns of the short-circuit winding, and the inter-turn short-circuit current cannot be measured online without adding additional sensors. See reports of research results in this area

The difficulty of measuring the inter-turn short-circuit current makes the fault-tolerant control of the motor system under the inter-turn short-circuit fault a technical difficulty

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