Sliding Mode Control in Power Converters

Abstract

Switched mode power converters are being used extensively for the purpose of efficient power conversion. Such converters are nonlinear, time variant systems. In the past such converters were being modelled using the state space averaging method. The theory of variable structure systems (VSS), and sliding mode control form a mutually complementary analysis and design tools for the control of switched mode power converters. The application of sliding mode control is presented for dc-to-dc converters and electrical motor drives in this thesis. The concept of sliding mode control is brought out through exhaustive examples of second order systems. The equivalent control, an analysis method of VSS, is applied to obtain transfer function description of dc-to-dc power converters. The sliding mode control is applied to the control problem of dc-to-dc power converters and speed controlled electrical drives to develop practical design techniques. The practical design methods are confirmed through experimental results.