Control Strategy for Virtual Synchronous Generator Based on Y-Z Source Inverter in Islanded Grids

The Virtual Synchronous Machine (VSM) concept stands as a strategy for the seamless integration of renewable energy sources into the grid. In scenarios where symmetrical and sinusoidal operating conditions are lacking, VSMs demonstrate multifaceted capabilities. They can operate as power sources especially in islanded-systems, adeptly address harmonic distortions and imbalances, offer load power compensation, and elevate voltage quality at the grid. Even so, dead time variations, discontinuous input current, and non-single-power-stage configuration of conventional voltage/current source inverters and also, load variation can result in VSMs behaving as harmonic and imbalance absorbers. This paper utilizes a specific Y-Source Inverter (YZSI) for the first time as a solution to these challenges. Through integrating this innovative configuration with an exceptionally adaptable voltage gain and an enhanced multi-loop control strategy into an isolated power system accommodating diverse load profiles, it not only achieves high efficiency in power transfer but also enhances overall system performance quality. Furthermore, it contributes to extending the lifespan and preserving the quality of the input source. The controller is designed to regulate system frequency, voltage, and manage voltage and current for YZSI, delivering impressive performance even in non-ideal grid conditions. MATLAB/Simulink confirms the efficacy of the proposed YZSI VSG control strategy with a high accuracy achieved through a comprehensive examination of the internal component parameters.