通过压缩机低压启动实验 ,采用临界状态比较法和启动时间比较法探讨了不同型号压缩机的最佳启动电容 ,实验表明随压缩机功率增大启动电容相应增加。同时研究了压缩机低压启动影响因素 ,确立了启动继电器、热保护装置与压缩机的良好匹配 ,进而开发复合启动装置 ,既保护压缩机又使下限启动电压达 140 V Through the compressor low-voltage start-up experiment, the best start-up capacitance of different types of compressors was discussed by the comparison of critical state and start-up time comparison method. Experiments show that the starting capacitor increases with the increase of compressor power. At the same time, the influencing factors of compressor low-pressure start-up were studied, and the good match between start relay, thermal protection device and compressor was developed. Then the compound start-up device was developed, which not only protected the compressor but also brought the lower limit starting voltage up to 140 V