Review of coupled inductors in power electronics: From concept to practice

Abstract

With the increasing complexity of power electronics converters, magnetic components like inductors, transformers in different configurations, etc., play important roles in shaping a power controller to meet its desired performance effectively and efficiently. Now, coupled inductors have emerged as one important category of magnetic components that can improve the performance of several types of power controllers used in different domains. They are used to improve the control response, reduce ripple content of output control variables, improve efficiency, enhance power density, etc. This review paper deals with coupled inductors in two ways. Firstly, it details the application prospects as well as design requirements for different applications of coupled inductors. Later, it deals with the design and practical validation of one coupled inductor essentially required for one complex application where the leakage inductance of each winding should be minimal. This review has analyzed that the magnetic circuit design would play a dominant role where both the soft magnetic material and winding layout would be extremely important. While designing a practical coupled inductor, this review article has further analyzed that a core material with low loss density, high saturation flux density and interleaved winding would make the ideal magnetic circuit. The proposed magnetic circuit has been thoroughly validated in a parametric-sensitive power controller for alternating current tungsten inert gas (AC TIG) welding.