Energy Efficiency
Case study for a fan system
Case study on energy savings in variable flow fan systems.
Energy Efficiency
Energy efficiency – Part 7 (How to calculate)
How to calculate energy and cost savings Our series on energy efficiency continues. The need for more energy efficient systems emerges day by day driven by increasing environmental concerns. Today’s post will guide you through calculation of energy and cost savings when utilizing a VFD in flow control. Energy savings Read more
Excursions and tours
Blast furnace Dolni Vitkovice
Blast furnace plant Dolni Vitkovice In this series we look into industrial and utility plants that benefit or could benefit from the usage of medium voltage variable frequency drives. Today our excursion leads us to a former blast furnace plant Dolni Vitkovice in Ostrava, Czech Republic [1]. Previous Next The Read more
LCI versus VSI
LCI vs VSI – Part 4 (Comparison – continue)
#LCI versus VSI:Part 4: Comparison (continue) Our series LCI versus VSI belongs to some of the most popular in this blog. We talk about the main medium voltage high power VFD technologies, Load-commutated Inverter (LCI) and Voltage Source Inverter (VSI), and compare them in various aspects. This post is a Read more
VFD transformers
VFD transformers: Harmonics
VFD transformers and harmonics Introduction The next post in our series discusses VFD transformers and harmonics. We have already learned what harmonics are and how they impact the supply grid (Network harmonics – intro). In this series we look more specifically into harmonics and their impact on VFD transformer. Motivation Read more
VFD transformers
VFD transformers: Multi-winding design
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
VFD transformers
VFD transformers: Introduction
VFD transformers: Introduction After reading this blog post you should understand the purpose of a VFD transformer and the differences between distribution/power transformer and a VFD transformer. Let’s start with the definition of a VFD transformer: This term refers to the input isolation transformer that supplies the rectifier section of Read more
Uncategorized
Literature in power electronics and variable frequency drives
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
Network harmonics: Introduction
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
Variable speed technologies
Comparison of VFD and fluid coupling
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