How to choose a medium voltage VFD: Cooling type This post looks into drive classification according to cooling. Same as for instance electric motors also VFDs can be divided in two main groups with regards to VFD cooling type: Air Read more
How to choose a medium voltage VFD: Application requirements The requirements of your application are key when selecting suitable VFD. If you check the websites of leading medium voltage VFD manufacturers you will find several products with different performance data. Read more
How to choose a medium voltage VFD (Part 1: Introduction) We start a new series dedicated to the selection of medium voltage variable frequency drive. Some points might also be valid for low voltage VFDs. However, many topics require different Read more
Reliability and availability (Part 4: IGCT based converters) IGCT is a power semiconductor used in medium voltage converter applications. The abbreviation stands for Integrated gate-commutated thyristor. Unlike classical thyristor that can only be switched on, IGCT can be switched on Read more
What challenges you face when dealing with Variable Speed Drive Systems? Variable speed drive systems (VSDS) represent complex systems requiring expertise in power electronics, electric motors and transformers, control engineering etc. Moreover, interactions between VSDS and electric grid on one Read more
Reliability and availability (Part 3: Semiconductor redundancy) Today we gonna talk about N+1 semiconductor redundancy. When is it needed? What are the benefits and drawbacks? The main purpose of redundancy is to increase reliability and availaibility of a system. Therefore, Read more
Project specificationsToo little / too much? In this post we talk about balancing the length and especially the content of project specifications. What is too little and what is too much? How to specify your requirements? Let us spend some Read more
#LCI versus VSIPart 2: Truth and lies about LCI and VSI We continue our series about the high power drive champions LCI and VSI. The introduction [1] last time was a bit longer, but the goal was to provide a Read more
LCI versus VSIPart 1: Introduction LCI (load-commutated inverter) and VSI (voltage source inverter) are the dominant technologies when it comes to high power medium voltage drives. Each technology has certain advantages as well as drawbacks. Project specific conditions and requirements Read more
#Energy efficiencyPart 3: Selection of VFD technology What type of VFD technology fits the best your demands? The answer depends mainly on your process and operation philosophy. Process dynamics Is your process very dynamic and fast response is required? Then Read more