Voltage Control of Dc-Dc Buck Converter and its Real Time Implementation Using Microcontroller

Abstract

The switched mode dc-dc converters are some of the simplest power electronic circuits which convert one level of electrical voltage into another level by switching action. These converters have received an increasing deal of interest in many areas. This is due to their wide applications like power supplies for personal computers, office equipment, appliance control, telecommunication equipment, DC motor drives, automotive, aircraft, etc. The analysis, control and stabilization of switching converters are the main factors that need to be considered. Many control methods are used for control of switch mode dc-dc converters and the simple and low cost controller structure is always in demand for most industrial and high performance applications. Every control method has some advantages and drawbacks due to which that particular control method consider as a suitable control method under specific conditions, compared to other control methods. The voltage control of buck converter using PI, PID controller ,PIDSMC and microcontroller based PID control are modelled and are evaluated by computer simulations.. In addition to this, the closed loop feedback system using PID controller method will be implemented against transient response in the system. This project is only limited to design the closed-loop feedback system using proportional technique for buck converter. The controller will be implemented on a PIC microcontroller and programmed through a computer using software of Mp Lab C compiler. The programmed microcontroller will be able to automatically control the duty cycle of the system in order to apply an appropriate duty cycle to the system. It has been found that the transient performance and steady state performance is improved using microcontroller based PID controller. The experimental system is found to be more advantageous and cost effective with microcontroller.