Comparative Analysis of Nonlinear SMC Controller with Linear PID Controller for Flyback Converter

Abstract

Power stability is a key importance in many high-speed switching power electronic systems today, ranging from portable desktop computing systems to electromotive vehicles, especially when moving to high power technologies. Switching power converters whether AC–DC or DC–DC plays major role in power supply, medical, automobiles naval ships equipment, etc., and have become pervasive. It is necessary to operate a converter smoothly throughout its operation under loaded condition. In this chapter, the importance of robust control of sliding mode controller (SMC) over linear PID controller of flyback converter is studied. Sliding mode controller not only provides fast response against supply, load and circuit parameter variations but also extreme robustness. In this chapter, flyback converter is implemented with sliding mode control to obtain a regulated output voltage in response to line, load and set point variation.This chapter gives the procedure to design a flyback converter (230 V DC–5 V DC) functioning under discontinuous conduction mode. Designing its model in MATLAB and studying its performance in closed-loop operation using nonlinear controllers and studying its stability with respect to open-loop configuration by implementing state averaging method linearize the structure and make simpler in designing technique. Robust designing of flyback converter using nonlinear SMC technique is used to regulate the flyback converter.The dynamic model of flyback converter is designed on MATLAB/Simulink, and then the two controllers, i.e., linear PID and nonlinear SMC are introduced. The performance is analyzed for both the controller. Finally, the implemented model and simulation result validates that the SMC control has advantage over linear PID controller.KeywordsFlyback transformerDigital power converterDC–DC converterContinuous conduction modePID controllerFlyback converterSliding mode controller