How does skin effect impact the drive system? This short article provides a brief description of the skin effect and its impact on a drive system. As it will be explained, the skin effect influences the system in both negative Read more
DTC in a nutshell Direct torque control, DTC, is a motor control method famous for its superior dynamic properties. Less known is the fact that DTC optimally utilizes the switching frequency to achieve the target: regulation of torque and flux Read more
Triplen harmonics – A devil in your network software tool? This blog post addresses potential “issues” with triplen harmonics when performing a network harmonic study. Positive, negative and zero sequence The theory of symmetrical components tells that a periodic signal Read more
What is the difference between cold and hot commissioning? Recently we got a question in our chat group about cold commissioning. That inspired us to write this short post on the difference between cold and hot commissioning. We will focus Read more
Can 50 Hz rated equipment operate on 60 Hz grid and vice versa? Globalization affects various areas of our lives. Variable speed drive systems are no exception. It happens that components manufactured in a “50 Hz country” will be used Read more
Drive systems according to their working principle Electric drives have many excellent properties that make them a preferred choice [1]. However, there are other types of drives based on other physical principles that also have their own strengths. In this Read more
What is a Phase-Shifting Transformer? VFD multi-winding transformers typically use phase-shifting feature in order to eliminate (cancel) certain harmonic orders in the spectrum of the current drawn from the grid. There are, however, other transformers that also use phase-shifting, but Read more
What is transformer K-factor? Transformers supplying power electronic equipment are exposed to non-sinusoidal load current. The harmonics cause additional losses in the transformer. One way to express the transformer design with respect to immunity against harmonic distortion is so called Read more
Why is it important to keep reasonable switching losses? Switching frequency is a decisive design parameter of a VFD – especially in medium voltage drives where the semiconductor capability may be more restricted. But switching losses have much bigger impact Read more
LCI celebrates 50 years anniversary! It is little bit hard to believe but the high-power drive champion LCI celebrates 50 years anniversary in 2024. We take this opportunity to look back at the history of this matador and maybe also Read more