Variable-speed control device used with induction motor together

Abstract

This variable speed controller consists of a voltage command value computing circuit, an integrator computing a phase angle command value from a primary angular frequency command value, and a power conversion circuit for conducting power conversion according to an alternating voltage command value vector, based on an alternating voltage command value and a phase angle command value. The device is provided with a current detector, an inductive voltage computing circuit, a displacement computing circuit, and a compensator. Setting the displacement of coordinate axes between the variable speed controller and the induction motor to be zero, thereby the efficiency of a motor can be improved.

Description

technical field [0001] The present invention relates to a variable speed control device which calculates an AC (Alternating Current) voltage command value by using a primary angular frequency command value and a secondary magnetic flux command value, and supplies the voltage command value to a power conversion circuit such as an inverter or the like. drive induction motors. Background technique [0002] FIG. 1 is a block diagram showing the whole of a conventional variable speed control device used with an induction motor. [0003] In this figure, the voltage command value calculation circuit 4 is based on the primary angular frequency command value ω 1 * and secondary flux command value φ 2 * To calculate the voltage command value v in the rotating coordinate system (d-q axis) 1d * and v 1q * , and output the calculated value, where the primary angular frequency command value ω 1 * and secondary flux command value φ 2 * is the output of the command value generat...

AI Technical Summary

Problems solved by technology

[0007] As a result, magnetic flux according to a command value cannot be generated, which leads to a decrease in the generated torque or the efficiency of the motor, etc.

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