Method and device for fault-tolerant predictive control of loss-of-excitation faults for permanent magnet synchronous motors

Abstract

The invention discloses an LOE (loss of excitation) fault tolerance prediction control method and device for a permanent magnet synchronous motor, and the method comprises the steps: obtaining the rotating speed, voltage and current of the permanent magnet synchronous motor, designing an LOE torque detection sliding-mode observer, obtaining an LOE disturbance estimation value and the observation value of the rotating speed, carrying out the fault tolerance prediction and rotating speed control to calculate a q-axis instruction current, designing an LOE flux linkage detection sliding-mode observer, obtaining a current observation value and a state current observation value after the LOE of a permanent magnet, carrying out the fault tolerance prediction and rotating speed control to calculate an instruction voltage, carrying out the inverse Park transformation and modulation through an SVPWM module, and generating a PWM pulse signal. The device comprises program units corresponding to the steps. The method achieves the quick and no-static-error tracking of the rotating speed and current of the permanent magnet synchronous motor under the LOE condition of the permanent magnet, optimizes the control performances of a rotating speed ring and a current ring, and facilitates the application of the permanent magnet synchronous motor in a severe environment and occasions with higher requirements for reliability.

Description

technical field [0001] The invention relates to the control technology of a permanent magnet synchronous motor, in particular to a method and device for a fault-tolerant prediction control method and device for a loss-of-excitation fault of a permanent magnet synchronous motor. Background technique [0002] In recent years, direct-drive wind power generation systems with brushless permanent magnet synchronous motors have been more and more widely used. People have also put forward higher requirements on the control performance of permanent magnet synchronous motors. Vector control is the most commonly used method for high-performance control of AC motors, and the control of the speed loop and current loop is the key. The traditional speed loop and current loop controllers are PI controllers, which are widely used in permanent magnet AC motor drives due to their simplicity and robustness. However, the permanent magnet synchronous motor is a multivariable, strongly coupled n...

AI Technical Summary

Problems solved by technology

However, in engineering practice, the operating conditions of permanent magnet synchronous motors are complex, and the environment varies greatly. With the increase of service life, the permanent magnets of the rotor are subject to electromagnetic, thermal, mechanical and other stresses, which will cause demagnetization failures.

The loss of excitation fault will cause the flux linkage parameters of the predictive controller motor model to be inconsistent with the actual motor flux linkage parameters

This will directly affect the performance of the control system, resulting in reduced traction system efficiency, failure to output rated torque, and failure to work in torque control mode.

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