Sequence Components
What are positive, negative, zero sequence components in power system and how do you calculate them? Three phase electric power…
Reactive Power Measurement
Reactive power is the power required by inductive devices (motors, transformers etc.) in power system to create magnetic field necessary…
Neutral Inversion and Neutral Displacement
Neutral inversion, Neutral shift or Neutral voltage displacement is the phenomenon in which the imaginary neutral of an ungrounded system…
Line Reactor vs Isolation Transformer
Line Reactor Line reactor as used in VFD/VSD application is an inductive component used in the line side or supply…
Calculating Phase Difference Between Two Waves
Often we will have two sinusoidal or other periodic waveforms having the same frequency, but is phase shifted. To calculate…
Troubleshooting VFD Problems – How to Measure DC Bus Voltage and DC Ripple
Introduction: Some of the frequent and troublesome VFD faults are related to the DC bus voltage. The VFD control circuit…
Troubleshooting VFD Problems – Overvoltage Fault
Drive (VFD) overvoltage protection for common low HP drives is based on the measured voltage on the DC bus of…
Line Reactor vs DC Choke
Line Reactor Line reactor as used in VFD/VSD application is an inductive component used in the line side or supply…
DC Choke for VFD
A DC choke (DC Link Choke) is used between the rectifier section and the bus capacitor section of a variable…
Medium Voltage Cable Construction
A power cable could appear as a simple electrical device, a conductor wrapped in an insulation. However, as you can…