Method for suppressing torque ripple of permanent magnet synchronous motor

Abstract

The invention discloses a method for suppressing torque ripple of a permanent magnet synchronous motor. The method comprises the following steps of establishing a mathematical model of the permanent magnet synchronous motor PMSM under a dq rotating coordinate system; establishing a load torque expression of the PMSM in the dq rotating coordinate system; adopting a disturbance torque observer to estimate the current compensation amount corresponding to a disturbance torque in real time; establishing an improved disturbance torque observer; obtaining a transfer function variable quantity; obtaining a sensitivity function and a supplementary sensitivity function of a transfer function; verifying the stability of the improved disturbance torque observer; and introducing the improved disturbance torque observer into a PMSM torque control system, so that the effect of restraining PMSM torque pulsation is achieved. According to the invention, the torque observer is adopted to suppress the voltage error generated by the disturbance torque, a quasi-differential observer is constructed to suppress the amplification effect of a differential link on the error signal, and the anti-interferencecapability of the control system is improved when the PMSM operates at a medium-low speed.

Description

technical field [0001] The invention relates to a method for suppressing the torque ripple of a permanent magnet synchronous motor. The method is used to solve the problem that the control system is easily affected by the torque ripple when the motor is running at a medium and low speed. A disturbance torque observer is used to suppress the generation of disturbance torque voltage error. Background technique [0002] Permanent magnet synchronous motor (Permanent Magnet Synchronous Motor, PMSM) has been widely used in industry, especially in mining work such as locomotive traction and winch lifting, because of its strong load capacity. As a new type of stator frequency self-controlled synchronous motor, Compared with synchronous motors, PMSM can effectively solve the problem of rotor oscillation and out-of-step due to the self-controlled frequency modulation working mode, so it has been widely used in industry. However, when PMSM runs at medium and low speeds, it is suscepti...

AI Technical Summary

Problems solved by technology

However, when PMSM operates at medium and low speeds, it is susceptible to torque ripple, and there are problems such as cycle delays in current and voltage sampling and inverter output, which will lead to poor dynamic performance of the entire motor control system.

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