Modern and historical public transportation in Pilsen Our excursion today leads us to Pilsen, Czech Republic. The city is located in western Bohemia. It was founded in 1295. The distance from Prague is about one hour. It is easily accessible by car (highway Prague – Nuremberg), by train (direct trains 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…
Topics you would like to read about in 2020 Happy and prosperous new year from MB Drive Services! We would like to thank all our readers for your interest, support, comments etc. The year 2019 was a true success. Our blog reached over 11’000 views from more than 2’800 readers. Read more…
Experience with IGCT based VFD Introduction This is a continuation of our Reliability and availability series. To access all posts in this series please click here. In today’s post we will share an industrial experience with medium voltage IGCT based VFD. IGCT as heart of high-power frequency converter is used Read more…
VFD transformers: Multi-winding design Today we look at the design of multi-winding VFD transformer feeding variable frequency drives. These VFD transformers are often classified in the category of ‘special transformers’. What does it mean? Why are they special? If you want to get these answers and a little insight into Read more…
Literature on Variable Frequency Drives, Power Electronics and related subjects The purpose of this blog is to provide useful information about Variable frequency drives (VFD) and power drive systems that you might appreciate when working in this field (specifying, selecting, purchasing, operating, servicing/retrofitting, researching or developing tasks). The blog intentionally Read more…
Network harmonics:Introduction Apart from the numerous advantages of variable frequency drives, such as precise speed or torque control, smooth motor starting or energy savings, this technology also comes with specific challenges. One of them are the network harmonics. The good news is that there is a solution. Actually, there are Read more…
VFD versus fluid coupling Today we open a topic that might polarize our readers: Comparison between variable frequency drive (VFD) and a fluid (hydrodynamic) coupling. Of course, this blog is dedicated to VFDs. Nevertheless, we intend to provide an objective benchmark as far as possible. Please note that there is Read more…
Encoders in motor drive applications What is the purpose of encoder? When is it needed? What types of encoders are being used? This post shall answer some of these questions. VFDs are used to control the motor speed or motor torque. The actual speed is either estimated (speed sensorless control), Read more…