The Short Summary A healthy AHF typically produces two types of noise: A low hum from the internal reactor (inductor) and cooling fans. This is normal. A high-frequency "switching" whine or buzz from the Insulated-Gate Bipolar Transistors (IGBTs). This is usually very faint. If the noise becomes loud, intrusive, or changes significantly, it is often a sign of a problem. Detailed Breakdow...
The Problem: Variable Speed Drives Generate Harmonics What is a Variable Speed Drive (VSD/VFD)?A Variable Speed Drive (VSD), also commonly called a Variable Frequency Drive (VFD) or Adjustable Speed Drive (ASD), is an electronic device that controls the speed and torque of an AC electric motor by varying the motor's input frequency and voltage. How Do They Cause Harmonics?The internal design of a ...
IN any system containing nonlinear loads that use phase-angle control or abrupt switching, particularly those that draw a non-sinusoidal current. The specific range of "2nd to 51st" is a classic signature of certain technologies.Here are the most common places where you would find such a wide harmonic spectrum: 1. The Classic Example: Thyristor-Controlled Reactor (TCR) in SVC Plants This is the mo...