摘要：高压变频器在运行中根据需要切换至工频运行是一种非常重要的运行方式，然而如果高压变频器与工频电源之间切换不当，则会引起很大的冲击电流。本文提出了一种新型的在线变频切工频的方式和方法，并介绍了这一新型切换技术的原理。通过仿真和现场应用表明：该切换技术有效地避免了切换时的冲击电流，保证了电机的平稳过渡。

关键词：高压变频器；工频切换

Abstract: High-voltage inverter at power frequency operation is a very important operation, but if you switch between high-voltage inverter with variable frequency to power frequency improperly, can cause a great deal of shock current. In this paper, Proposed a new method of high-voltage i