Design, Analysis and Controller Design of Zeta Converter

Abstract

In this paper the design, analysis and controller design of zeta converter is explained. The Dc to Dc Zeta converter is a type of buck-boost converter that provides an dc output voltage with the same polarity of the input dc voltage. Zeta converter is more useful as compared to the other class of converters having the properties of both buck converter and the boost converter i.e. it can be used to provide the step up or step down the applied input voltage. It is usually used in different types of industrial and domestic applications. It provides an non-inverting polarity output dc voltage and it could be designed to obtain the lower ripple output current and as it has smaller settling time which makes the system more faster and increases the adaptability etc. The zeta converter is generally used to get the need of dc appliances by varying the dc output voltage. This paper focusses mainly based how to maintain the constant dc voltage and changing the dc voltage. At first by using MATLAB, ZETA Converter is designed. The dc output voltage of the converter is measured from output of the converter with open circuit. The duty cycle of the switch is varied to vary the output voltage which decides to operate the zeta converter either as a buck converter or as a boost converter. A feedback control design is necessarily required for achieving best voltage regulation, faster dynamic response, and to achieve the stability of the converter. Therefore, in this paper, State space technique is used to attain the small-signal Transfer function duty cycle to the output voltage of dc to dc Zeta converter. Then the Proportional Integral (PI) controller is designed using this transfer function and using the stability equations to attain the specific phase margin of the converter and to reach the required cross over frequency. The result of the simulation shows that the Zeta converter is compensated and also shows the best dynamic response and the steady-state behavior with the presence of load and line variations. The zeta converter is widely used in applications such as e-rickshaw, correction of power factor, for battery charging etc. Here the zeta converter is found to be 90-93% efficient.

Keywords; Zeta Converter, MOSFET (Metal Oxide Semiconductor Field Effect Transistor), SSA (State Space Averaging Technique), CCM (Continuous Conduction Mode), PI Controller and Simulink Model.