软切换技术在变频与工频切换中的应用

Application of soft handoff in inverting and fundamental frequency power supply

在变频器从变频和工频切换中,工频旁路运行是变频器的一种重要运行方式,变频器与工频电源之间切换不当会引起很大的电流冲击和严重的电磁干扰。提出了变频器与工频电源之间的软切换概念,论述了软切换的原理及其实现方法,使用PSCAD/EMTDC电磁暂态仿真软件对几种切换方式的仿真结果表明,变频调速系统的软切换方式有效地避免了过大的冲击电流,保证了电动机转速的平稳过渡。

This paper puts forwards the soft handoff concept between the inverting and fundamental frequency power supply and discusses its principle and realization. The simulating effect by electromagnetic transient simulation software shows that the soft handoff avoids effectively the excessive impulse current and guarantees the smooth and steady transition of the motor speed.