西门子6RA70在同步机励磁电源上的应用

Application of Siemens 6RA70 in the Synchronous Motor Excitation Source

中压变频器软启动是中压大功率同步电机变频调速系统中的一种典型应用,而在与电网同步跟踪和切换过程中,励磁电源的性能及其动态控制起关键性作用。本文提出用西门子全数字直流调速装置6RA70标准产品,改造成电流型励磁电源,并与西门子S7-200型 PLC 一起构成完整的同步电机励磁控制系统。两年多的运行结果表明:6RA70励磁电源的输出电流纹波小、动态响应快,完全满足软启动的同步跟踪快速的要求,同步切换成功率达100%,且日常运行稳定可靠。

The soft starting of the middle voltage inverter is one typical application of the large power and middle voltage synchronous variable frequency drives. During the switchover and the synchro-tracking, the performance and dynamic control of the excitation source are key. This paper describes one new current-source exciter with siemens 6RAT0 digital I）C drive , and one synchronous exciting control system can be developed by integrating $7-200 PLC. After two years more than, the running result indicates that the 6RAT0 exciter has low current ripple and good dynamic, and meets the all needs for the fast synchro-tracking. 100% successful switchover and good stabilization and reliability have been achieved.