Performance evaluation of voltage and current control mode controller for SEPIC converter in CubeSats application

Abstract

Front-end power converters for satellite application demand better performance in terms of accurate reference tracking because of the wide-range input voltage of the solar panels. The very tight output voltage requirements demand for robust, reliable, and higher efficiency. The control of such converter is very complex and time consuming to design. Two commonly used control modes are current and voltage control. The design and implementation of a voltage controller for power converter is simpler but not do provide for overcurrent protection compared to current mode controller. Single-ended primary inductance converter is selected in this research work because of its ability to buck or boost the input voltage coupled with the ability to provide non-inverting polarity with respect to the input voltage. Parameter values for the studied converter is used to analyse and design both current and voltage mode controllers for performance evaluation. Output voltage reference tracking with step and ramp changes in input voltage is evaluated in terms of the time taken to reach steady-state after the injected disturbances and the overshoot or undershoot of the output voltage reference. Changes in the output voltage reference to load changes are also studied considering the two controllers. The modelling and simulation work was done on PSIM simulation platform. The controllers design and implementation was carried out using the Smart-Control added module on the PSIM simulation platform. Results show that the current mode controller performed better than the voltage mode controller in terms of the reference tracking and disturbance rejection.