Voltage Sag Ride-Through of Super High-Speed Turbo Compressor

Turbo compressors have been extensively used in the factory automation as a part of pneumatic manipulators. Authors developed a position sensorless super-high speed turbo compressor, and it has been installed and working at the industrial plants for years. But repeated failures have been reported at some specific sites. In this paper, the repeated failures are analyzed through experiments and theoretical approach and the remedy against the failures is proposed. Through the analysis, it is presented that there are current overshoots at the instances of voltage sags due to the time delay of dc-link voltage measurement, and the overshoots sometimes trip the inverter even after the voltage sags are cleared. And, the measurement circuit has been modified to reduce time delay. The proposed method has been applied to the failure sites, and the repeated failures have been disappeared.