Open-phase detection method for permanent magnet synchronous motor based on vector control

Abstract

The invention discloses an open-phase detection method for a permanent magnet synchronous motor based on vector control. The method is characterized by comprising the following steps of: judging an open-phase state by utilizing the fluctuation amplitude of q-axis current iq in a dq axis of a rotor rotating coordinate system, and when the q-axis current iq has small fluctuation and tends to a stable direct-current component, regarding the state as a normal state; and when the q-axis current iq fluctuates in a sine state and the fluctuation amplitude is large, regarding the state as an open-phase state. The method is not limited by a current sampling mode, is wide in adaptability, smaller in program code quantity, quicker in judgment, capable of quickly judging the open-phase state in the starting and operating stages, has certain anti-interference capability, is simple, quick and efficient, is small in calculation quantity, basically does not consume chip resources, is high in judgment logic accuracy, and is easier to realize an open-phase protection judgment strategy.

Description

Technical field: [0001] The invention relates to a phase loss detection method of a vector-controlled permanent magnet synchronous motor. Background technique: [0002] The permanent magnet synchronous motor with Hall sensor can always sense the rotor position and speed information through the Hall sensor, so the whole control is stable and reliable. However, the introduction of the Hall sensor will increase the size and cost of the motor, and because the addition of the Hall sensor requires additional wiring, interference between the wiring is likely to occur, thereby reducing the performance of the motor. In addition, the Hall sensor needs to be installed accurately, which greatly increases the difficulty of the production process of the motor. Therefore, adopting the Hall sensorless control strategy has great practical significance. At present, many manufacturers are gradually promoting permanent magnet synchronous motors without Hall sensors, which solves the disadvant...

AI Technical Summary

Problems solved by technology

However, in order to reduce the cost of the controller as much as possible, two current sampling circuits are usually used to sample the 2-phase coil windings in the three-phase non-inductive vector control permanent magnet synchronous motor, or a single current sampling circuit is used to sample the three-phase non-inductive Sampling the total current (or bus current) of the 3-phase coil windings in the vector-controlled permanent magnet synchronous motor will inevitably increase the difficulty of the control algorithm, the judgment process is cumbersome, the amount of calculation is large, chip resources are consumed, and the accuracy of judgment logic is reduced. The difficulty of judging strategies for lack of phase protection is also greatly improved

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