Method for measuring rotating speed of reciprocating-type refrigeration compressor

Abstract

The invention discloses a method for measuring a rotating speed of a reciprocating-type refrigeration compressor. The method comprises the following steps of: (1) collecting exhausting pressure signals in such a manner that a pressure sensor is installed an exhausting port of the reciprocating-type compressor, a high-speed data collection card is simultaneously adopted for data collection, and collected data is sent to a computer after high-speed A / D conversion; (2) pre-processing signals in such a manner that the data after the high-speed A / D conversion is filtered by a filter, and polynomial trend terms are eliminated after the filtering; and (3) analyzing the signals in such a manner that analyzing the signals after the early-stage data pre-processing, and the frequency of the pressure signals are extracted. The method has the advantages that: (1) the magnitude of the exhausting pressure reflects the magnitude of the rotating speed, the measurement is relatively direct, and intermediate errors are avoided; (2) compared with a current measurement method adopting FFT, the precision is substantially improved; (3) the device is simple, and online measurement is realized; and (4) the method is not just applicable to a small-scale refrigeration compressor, the rotating speeds of all reciprocating-type refrigeration compressors can be measured, and the application range is wide.

Description

technical field [0001] The invention relates to the technical field of measuring the rotational speed of a reciprocating refrigeration compressor, in particular to the fields of refrigeration systems, pressure measurement, high-speed data acquisition, digital signal processing and the like. Background technique [0002] As the core component of the refrigeration system, the compressor's technical indicators directly affect the performance of the entire refrigeration system, and the operation of the compressor is essentially the rotation of the motor, that is, the compressor speed. The speed affects the cooling capacity, efficiency ratio, power consumption, suction and exhaust pressure of the refrigeration system, so the compressor speed is an important technical indicator. [0003] At present, small refrigeration compressors are all fully enclosed, and the traditional measurement method has certain defects. Among them, the direct method uses a sensor installed inside the co...

AI Technical Summary

Problems solved by technology

Among them, the direct method uses a sensor installed inside the compressor to measure the rotational speed, but this will undoubtedly cause certain damage to the compressor, which does not conform to the principle of measurement; the other is the indirect method, which mainly measures the vibration frequency and vibration frequency of the compressor at present. Compressor current, the former is difficult to distinguish due to the interference of other frequencies close to the vibration of the compressor while the compressor is running, and the latter has certain limitations in the measurement device and accuracy

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