Variable frequency drives aka VFDs are the heart of modern electrical motor controls. A VFD is made up of various electronic components which take a fixed frequency as input and provide a variable frequency output. A VFD is made of three parts. Rectifiers, filter, and inverter. Rectifier takes ac input, converts to dc, then after passing through the filter again inverter takes the input and provides AC output to the ac motor.
In this whitepaper, a brief, technical, yet very simple and easy to understand introduction is provided. The concept based indenture starts with the reason, “Why we need variable frequency controls”, it relates the need with mathematical equation S = 120 f/ n and the relates the concepts with the topic. In the latter part, the physical construction and technical details of working are shared.
This whitepaper contains 6 pages on VFDs and is very important for Electrical Engineering students, Electrical Technicians, and Engineers who want to improve their practical knowledge and who love to learn about modern electrical power systems.