New robust controller design for voltage source inverters in microgrids

Abstract

Renewable energy sources such as Solar, wind etc. have gained a lot of interest and application in the recent years, as they can provide electric power on a large scale and are environment friendly. The advancement in the technology of these renewable energy systems has been investigated now a days with a lot of interest. An integral component of the power electronics system that interfaces a renewable energy source to the main power grid is the voltage source inverter (VSI). The purpose served by VSI is converting the DC output of the power source to smooth sinusoidal AC for connection to the main grid. A controller also needs to be designed for the VSI to regulate its output voltage and/or output power. Several issues relevant to the control design have been extensively addressed including vulnerability of the system to parameter variation and uncertainty. In this research work we propose, to design a new robust reference tracking controller, its application and, implementation. The robust controller should be designed such that systems performance in presence of uncertainty improves in comparison to the existing control methods. We will develop the robust control law based on the results presented in a recent research work. To achieve reference tracking, the controller will be augmented with an integral controller. Simulation results will be provided at the end to show good reference tracking performance and significant improvement in the performance of the system in the presence of uncertainty.