Three-phase motor frequency conversion speed regulation system with output sine wave frequency up to 20000hz

Abstract

A three-phase motor variable frequency speed control system capable of outputting sine waves with the frequency as high as 20000Hz comprises a DSP processor, three groups of three-phase drive PWM signals used for outputting phases with the difference of 120 degrees and three-phase amplifying channels, wherein the structures of the three-phase amplifying channels are identical, and the three-phase amplifying channels are distributed in parallel, receive the corresponding three-phase drive PWM signals sent by the DSP processor respectively, improve the frequency of the three-phase drive PWM signals to be larger than or equal to 20000Hz and are used for controlling a drive circuit to drive a motor. The three-phase motor variable frequency speed control system has the advantages of being smooth in output wave shape, low in motor operation noise, smooth, high in signal-noise ratio, little in signal distortion, wide in dynamic range, good in circuit stability, strong in anti-interference performance, capable of allowing digital or analog signals to be input, and flexible to use.

Description

technical field [0001] The invention relates to a three-phase motor frequency conversion speed regulation system with output sine wave frequency up to 20000Hz. Background technique [0002] At present, if you want to do a low-power motor performance test, the signal generator can generate a sufficiently high-frequency sinusoidal signal, but it is impossible to load it. The frequency converter can output high power, but the output frequency is too low, and the wiring debugging is complicated. If the known common three-phase AC motor works with a power frequency of 50 Hz, it can only be used in fixed speed situations such as 3000 rpm and 1500 rpm. Ordinary frequency conversion adjustment range is also limited, which limits the scope of use of three-phase motors. Moreover, the PWM frequency of ordinary inverters is generally low, only tens of KHz, and the output sine wave frequency of the drive is low, generally only a few hundred HZ, and the waveform is not smo...

AI Technical Summary

Problems solved by technology

Ordinary controller with slow running speed and limited I / O, which is not conducive to the overall function expansion of the drive

Ordinary drive circuits are generally only used for high and low voltage isolation, not all signals are isolated, and the anti-interference performance is not good enough

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