Control method and control system for permanent magnet synchronous motor using large moment of inertia

Abstract

The invention discloses a control method and a control system for a permanent magnet synchronous motor using a large moment of inertia. The control method comprises the following steps: 1) calculatingthe actual rotational speed of the motor, and calculating the torque current and the excitation current of the motor; 2) comparing the actual rotational speed with a preset rotational speed to obtaina deviation value, and outputting a current reference value via a speed regulator; 3) according to the motor speed increase and deceleration states, executing corresponding inertia compensation strategies; 4) comparing a torque current with the reference value of the torque current adjustment to obtain a comparison value, and then obtaining the output values of the AC and DC voltages via a current regulator; 5) obtaining the reference values of the AC and DC voltages; and 6) performing a space vector algorithm based on the reference values of the AC and DC voltages to obtain a PWM drive signal, and controlling the operation of a three-phase inverter bridge drive motor. Based on the double-loop vector control of the rotational speed current, the voltage feedforward decoupling and the moment of inertia feedforward control are designed to compensate the motor current in real time, which accelerates the dynamic response to the large moment of inertia load and improves the accuracy and rapidity of permanent magnet synchronous motor control system.

Description

technical field [0001] The invention belongs to the technical field of AC permanent magnet synchronous motor control, and in particular relates to a control method and a control system of a permanent magnet synchronous motor applying a large moment of inertia. Background technique [0002] AC permanent magnet synchronous motor has the advantages of high power density, excellent regulation performance, and good maintainability, and can work in two modes of driving and power generation. Therefore, it is generally used as a flywheel drive motor in flywheel energy storage devices. Since the flywheel is a load with a large moment of inertia, the following problems exist in the process of using a permanent magnet synchronous motor to drive the flywheel: If the power of the motor control system is large, with a large moment of inertia and high-speed motor, once a fault occurs, even if the input of the motor control system is disconnected Open, the inverter stops running, because th...

AI Technical Summary

Problems solved by technology

Since the flywheel is a load with a large moment of inertia, the following problems exist in the process of using a permanent magnet synchronous motor to drive the flywheel: If the power of the motor control system is large, with a large moment of inertia and high-speed motor, once a fault occurs, even if the input of the motor control system is disconnected Open, the inverter stops running, because the output switch is not disconnected, and the motor with large moment of inertia runs at high speed, causing the back electromotive force of the motor to "fed back" to the DC side of the diode rectifier, resulting in an increase in DC voltage, and even breakdown of the motor control system SCR module

[0003] At the same time, when the speed of the flywheel changes, a large inertia torque will be generated, which will cause the motor current to oscillate during the control process, increase the tracking error, and slow the speed response, etc., resulting in a decrease in the performance of the motor control system.

Images