IMPROVED SLIDING MODE CONTROL FOR PARALLEL INVERTER IN GRID CONNECTED PV-SYSTEM

Abstract

The voltage inverters (VSI) are used to integrate the different sources into the microgrid. VSI must be controlled in such a way that they will be able to remove the non-linearity, to give high steady performance, fast response, and robustness. Anyhow it is impossible for all the ordinary controls to fulfill the above requirement. In the control strategy there are the three main controls i.e., primary control, secondary control, and tertiary control. Primary control is the main control of the microgrid which improves the power sharing capability. In the primary control, we introduced the improved sliding mode control (SMC) in which the sliding surface depends on the variations of the load. In this technique the dynamics of the VSI depends on the sliding surface co-efficient (λ). Furthermore, due to the sliding surface co-efficient (λ) we reduce its reaching time due to which the robustness of the inverter will be guaranteed. In this proposed methodology improved sliding mode technique is used with the fixed switching and the optimal selection of θ. The proposed system will be to reduce its total harmonic distortion (THD), chattering due to its optimized selection mechanism of the sliding surface and θ which will improve the dynamic response of the system.