排气压力脉动的全封闭往复式压缩机转速测量方法  

Speed Measurement Method of Hermetic Reciprocating Compressors Based on Discharge Pressure Fluctuations

作　　者：金华强[1,2] 顾江萍 黄跃进[2] 孙哲 沈希 JIN Huaqiang;GU Jiangping;HUANG Yuejin;SUN Zhe;SHEN Xi(College of Education,Zhejiang University of Technology,Hangzhou,310023;College of Mechanical Engineering,Zhejiang University of Technology,Hangzhou,310023)

机构地区：[1]浙江工业大学教科学院,杭州310023 [2]浙江工业大学机械工程学院,杭州310023

出　　处：《中国机械工程》2018年第17期2060-2068,共9页China Mechanical Engineering

基　　金：浙江省基础公益研究计划资助项目(LGG18E050024)

摘　　要：提出一种基于排气压力脉动的全封闭往复式压缩机转速测量的新方法。全封闭往复式压缩机的吸排气阀片伴随着活塞的往复运动而开启与关闭,使压缩机吸排气产生压力脉动,排气压力脉动比吸气压力脉动明显。排气阀室较排气管出口压力脉动幅值明显,去除趋势项后经CZT变换得到的脉动频率和转速一致,故可将排气管出口压力作为新方法的采样信号。在不同压缩比工况下,新方法测得转速与压缩机实际转速进行对比,实验表明新方法在不同负载工况下都有效,精度为±1 r/min;测量时间为1 s。A method was proposed for measuring the speeds of hermetic reciprocating compressors based on discharge pressure pulsations.The suction and discharge valves of the hermetic reciprocating compressors were opened and closed with the reciprocating movements of pistons,resulting in pressure pulsations of compressor suctions and discharges,and the discharge pressure pulsations are more obvious than the suction pressure pulsations.The amplitudes of the pressure pulsations in the discharge chambers are higher than that in discharge pipes,and the speeds of compressor equal to the pressure pulsation frequencies with CZT after detrending.Therefore,the pressures in discharge pipes may be taken as the sampling signals for compressor speed measurements.Under different compression ratios,the speeds measured by this method were compared with the actual rotational speeds of the compressors.Experimental results show the effectiveness of the measuring method herein under different load conditions with the accuracy of±1 r/min and the measuring time of 1 s.

关 键 词：排气压力脉动 压缩机转速 线性调频Z变换 频谱细化 压缩比 

分 类 号：TB652[一般工业技术—制冷工程]