How do system parameters impact the grid harmonic distortion? VFD as a non-linear load produces harmonics that are injected into the grid and cause harmonic distortion. The level of harmonic distortion depends on the type of VFD, specifically the rectifier topology. However, it is also strongly affected by the parameters Read more…
Harmonic calculation versus network harmonic study As our regular reader you already have a solid knowledge about network harmonics caused by non-linear power electronic systems. It does not surprise you that network might have resonance(s) – a topic that needs to be addressed. Also, you are familiar with harmonic footprint Read more…
VFD transformers: Differential protection Differential protection of VFD transformers might be a controversial topic. The more a reason for us to bring it up, explain the principle, describe the advantages and drawbacks and provide our view and recommendation for the users. We hope that this article will be useful source Read more…
Network harmonics: Mitigation methods Today’s post focuses on harmonic mitigation methods. Let us review the most common, well proven methods of minimization of harmonic distortion on the grid side. Previous articles presented a general view on harmonics, their origin and effects [1]. The grid side harmonic spectrum of VFDs had 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…
How to choose a medium voltage VFD:Line side connection and power quality Nowadays modern VFDs offer large variety of line side configurations. Which one to select? That is the topic of today. There are two basic groups of VFDs based on their line side connection: Diode Front End (DFE) Active Read more…