Are surge arresters suitable for protection of VFD fed motors? Surge arresters are commonly used to protect electric equipment against excessive overvoltages. At the same time, many voltage source inverters produce non-sinusoidal voltages that stress the machine insulation. Thus, one could ask whether surge arresters are suitable means to protect Read more…
Overvoltage protection of transformers This is the continuation of [1] that made an introduction into protection of VFD transformers. The focus of this article is on overvoltage protection. Particular attention is paid to very fast transient overvoltages caused by switching of vacuum circuit breakers. Keep reading to learn about the Read more…
How to choose a medium voltage VFD:Protection concept A variable speed drive system with gaps in protection philosophy is a ticking bomb. It might have a huge impact on plant availability and potentially also on personal safety. Therefore, no compromises shall be accepted. Other topics in this series are definitely Read more…