A method for reducing the speed measurement error of variable frequency compressor through frequency division measurement

Abstract

The invention discloses a method for realizing reduction of rotation speed measurement error of a variable frequency compressor through frequency-division measurement. The method is a rotation speed measurement method for a variable frequency compressor of an air conditioner and a refrigerator, and realizes rotation speed measurement of the compressor by detecting the frequency of any phase of current in three phases of drive current of the variable frequency compressor. The method is characterized by detecting the current rotation speed of the variable frequency compressor and sending the detected rotation speed to an MCU. The rotation speed measurement method can accurately detect the rotation speed of the variable frequency compressor when the variable frequency compressor is at high speed and low speed, thereby reducing rotation speed measurement error. The method adopts a current transformer, an operation amplifier module circuit, a high-frequency filter circuit, a low-frequency filter circuit, a comparator module circuit and the MCU.

Description

technical field [0001] The invention belongs to the technical field of variable frequency compressors, and in particular relates to a method for reducing the measurement error of the rotational speed of a variable frequency compressor through frequency division measurement. Background technique [0002] At present, most inverter compressors of air conditioners and refrigerators are driven by sine waves. When the compressor is driven at a low speed, the current waveform is very poor, the current amplitude is small, and there is a lot of interference, resulting in the conventional inverter compressor speed measurement. The method measurement is inaccurate, and the error is very large. In view of this, this patent application is proposed. Contents of the invention [0003] The object of the present invention is to solve the shortcomings in the prior art, and propose a method for reducing the measurement error of the rotational speed of the variable frequency compressor throug...

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Problems solved by technology

[0002] At present, most inverter compressors of air conditioners and refrigerators are driven by sine waves. When the compressor is driven at a low speed, the current waveform is very poor, the current amplitude is small, and there is a lot of interference, resulting in the conventional inverter compressor speed measurement. The method measurement is inaccurate, and the error is very large. In view of this, this patent application is hereby proposed

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