Fault current considerations for integrated transformer of CHB drive Introduction Cascaded H-bridge (CHB) variable frequency drives (VFD) have the input transformer as an integral part of the VFD. This transformer has high number of secondary windings (equal to the number of VFD power cells). Such multi-winding transformer represents a challenge Read more
What types of VFD grid connection exist? How is the VFD connected to the supplying grid? There are several ways. In this post we look at the conventional ones as well as more specific solutions regarding variants of VFD grid connection. 1. Connection through at input isolation transformer Most common Read more
Combined transformer Our recent post [1] walked the reader through the two main VFD transformer options: integrated transformer and external transformer. Today we will introduce a solution that aims to leverage on advantages of both solutions: combined transformer. The name might be a bit misleading. We can also call it Read more
Integrated versus external transformer Modern variable frequency drives offer two options: integrated transformer or external transformer. How do these options compare? Which one is a better choice? INTEGRATED TRANSFORMER EXTERNAL TRANSFORMER There is no general answer. Instead, it depends on several aspects and project specific conditions. This post will walk Read more