Implementation of Emulated Inertia using PV Generation with Energy Storage to Improve Integrated Grid Response

Although the penetration of the distributed renewable energy sources into the traditional grid has risen over the past few decades, the potential negative impact of this integration can never be overemphasized. One issue is the absence of inertia in the renewable energy sources. To mitigate this problem, we describe the integration of virtual synchronous generators (VSG) based on the photovoltaic (PV) generation. To ensure the positive contribution of the PV to the stability of the grid, this paper models the VSG based on the swing equation to implement VSG control, bidirectional converter and grid-imposed inverter based on 7-bus ac system. These models are designed and simulated in an electromagnetic transient program (EMTP). This paper also examines the response of the grid under diverse varying conditions. The cases considered includes variations in the grid frequency, inertia time constant, active and reactive power. The control of the VSG was presented and the simulation results showing the effectiveness of the proposed control schemes were clearly discussed.