Four-phase brushless DC (direct current) motor fault-tolerant power converter and control method thereof

Abstract

The invention discloses a four-phase brushless DC motor fault-tolerant power converter and a control method thereof. The four-phase brushless DC motor fault-tolerant power converter comprises five inverting bridge arms, six bidirectional thyristors and ten fuses, a four-phase winding is connected to the midpoints of four of the bridge arms after forming two mutually-isolated channels, and the fifth bridge arms is a redundant bridge arm and only works during fault-tolerant operation; every power tube on every bridge arm is connected in series with a corresponding fuse, which can protect the system from being burnt due to short circuit faults and can convert the short circuit faults into open circuit faults for fault tolerance when the short circuit fault occur. The midpoint of every bridge arm is connected with a bidirectional thyristor for achieving fault tolerance of the power tubes; the neutral point of the winding and the midpoint of the fifth bridge arm are also connected with one bidirectional thyristor for achieving fault tolerance of the winding. The four-phase brushless DC motor fault-tolerant power converter is applicable to a four-phase permanent-magnetic brushless DC motor and a double-salient motor and can achieve open circuit and short circuit fault tolerance of power tubes and windings.

Description

technical field [0001] The invention relates to a four-phase brushless DC motor fault-tolerant power converter and a control method, belonging to the technical field of fault-tolerant motor control. Background technique [0002] Traditional three-phase permanent magnet brushless DC motors and three-phase double-salient pole motors can be driven by three-phase square wave currents. They have the advantages of large starting torque, high power density, and good speed regulation performance, and their application prospects are becoming more and more extensive. The brushless DC motor with four-phase redundant windings can still achieve a certain output after single-phase or multi-phase faults by using multi-phase windings. It has high fault tolerance and is very suitable for special vehicles, aerospace, etc. It is suitable for occasions that require high reliability of motor drive performance. [0003] Permanent magnet brushless DC motors and doubly salient pole motors may have...

AI Technical Summary

Problems solved by technology

Because a short-circuit fault will cause a large short-circuit current inside the winding, this short-circuit current will cause the motor to overheat and burn out.

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