Abstracto

Design of Buck-Boost Converter for Constant Voltage Applications and Its Transient Response Due To Parametric Variation of PI Controller

Abhinav Dogra, Kanchan Pal

Every Electronic circuit is assumed to operate off some supply voltage which is usually assumed to be constant. A voltage regulator is a power electronic circuit that maintains a constant output voltage irrespective of change in load current or line voltage. Many different types of voltage regulators with a variety of control schemes are used. With the increase in circuit complexity and improved technology a more severe requirement for accurate and fast regulation is desired. This has led to need for newer and more reliable design of dc-dc converters. The dc-dc converter inputs an unregulated dc voltage input and outputs a constant or regulated voltage. The regulators can be mainly classified into linear and switching regulators. All regulators have a power transfer stage and a control circuitry to sense the output voltage and adjust the power transfer stage to maintain the constant output voltage. Since a feedback loop is necessary to maintain regulation, some type of compensation is required to maintain loop stability. In this paper, a PI controller is designed and analyzed for a buck-boost converter. Stability analysis and selection of PI gains are based on the closed-loop error dynamics. PI controller, being the most widely used controller in industrial applications, needs efficient methods to control the different parameters of the plant. The output of the conventional PID system has a quite high overshoot and settling time.