VFD control: An introduction In this post we introduce basic thoughts on VFD control. Some of you asked deeper questions about different motor control strategies and their benchmark. Such comparison will be subject of a separate post, resp. a dedicated Read more…
Selection of a variable frequency drive In this post we walk through some aspects regarding selection of a variable frequency drive. Variable frequency drives, often abbreviated as VFD, VSD or ASD, are means to achieve energy savings [1] and to Read more…
Undervoltage Ride Through This post talks about VFD capability to withstand a fault in the supplying grid without tripping the drive system – undervoltage ride through function [1]. Availability of drive system is very important for many users and the Read more…
Current, voltage and power scaling of VFD Variable frequency drives (VFD) became unthinkable part of industrial motor drives. They cover voltages from some 120 V up to 13.8 kV (special designs go even higher) and power range from fraction of Read more…
Advantages of liquid cooled drives This article deals with liquid cooling for high power variable frequency drives (VFD). What is the principle of liquid cooling? What kind of liquid can be used for cooling? What are the advantages of liquid Read more…
VFD testing: Introduction Abstract This new series on VFD testing will guide you through various aspects of testing of variable frequency drives (VFD) and drive systems. We will discuss tests required by standards (particularly IEC), factory acceptance tests, site acceptance Read more…
Dealing with critical speeds This post explains some basic considerations related to variable speed motors and their critical speeds. The fact that motor operates at variable speed makes it more challenging from rotordynamic perspective in order to avoid critical speeds Read more…
VFD multidrives and investment cost Continuing our popular series on benefits of multidrives [1] we will talk about multidrive investment cost, especially when comparing it with alternative based on single drives. Introduction VFD multidrive solution offers plenty of benefits. Several Read more…
VFD multidrives: Grid harmonic performance This is the continuation of our short series on benefits of VFD multidrives [1]. We have already explained improved energy efficiency [2] and reduced footprint [3]. Today’s article focuses on grid harmonic performance and how Read more…
VFD multidrives: When footprint matters Reduced footprint as additional benefit of VFD multidrives VFD multidrive solution can, among other benefits (see [1]), substantially reduce the total space required for the installation. In this article we will explore the ways how Read more…