Variable Speed Motors – Which type suits the best? Electric variable speed drive system consists as minimum of a VFD and an electric motor. So the question is: Which motor type suits the best for variable speed control? As usual, Read more
Bearing damage stopped at the source Preface This article was written by our partner Mark Gurney from 3Phi Reliability [1]. Mark is sharing his vast experience related to reliability aspects of VFD fed motors. The examples are from low voltage Read more
Scalar control – What does it actually mean? Many times we see that the term ‘scalar control’ is used in incorrect way or being misinterpreted. In this article we will briefly discuss scalar control – what does it actually mean? Read more
What is your favorite high-speed train? It is holiday time!! And holidays are linked with travelling. Do you travel by train? What is your favorite high-speed train? Let us know in the comment section. Train belong to one of the Read more
What VFD properties matter the most to you? Medium voltage VFD is often a long term investment. The expected lifetime is typically at least 20 years. Thus, it is important to make the right choice when purchasing it. That is Read more
Why do VFDs sometimes trip during grid faults? Grid disturbances and faults appear now and then. And it is desirable that the VFD does not trip every time such event occurs. Thus certain immunity against grid disturbances is desired. In Read more
Types of harmonics How can we classify harmonics? What types of harmonics do we know? That is a subject of this short post. Different literature sources mention various classification. We just list here several categories based on our own practice. Read more
Overdimensioning of VSDS – What are the consequences? How to dimension a variable speed drive system (VSDS) properly? Underdimensioning is a No Go but what about overdimensioning? Besides the initial investment cost, how does overdimensioning affect the technical side of Read more
KYDS: Know Your Drive System KYDS -Know Your Drive System – is our new program where you learn more about variable speed drive system and the most important system components (transformer, VFD, electric motor, cooling system, harmonic filter). Scope of Read more
How to take oil samples properly? In this short blog post we share a basic guideline and set of recommendations how to take oil samples properly. Introduction Analyzing the quality of transformer insulation oil by means of oil samples is Read more