Real-time photovoltaic plant maximum power point estimation for use in grid frequency stabilization

As the amount of solar photovoltaic (PV) generation connected to electric grids grows, PV displaces conventional rotating machines whose inertia stabilizes the grid frequency on fast time scales. Therefore, especially in low-inertia grids, it may be desirable for PV inverters to control their output power to emulate the inertial response of conventional generators. This paper presents and validates through dynamic simulation a method of providing primary frequency regulation and inertia-like response from PV without energy storage by operating somewhat below maximum power. A novel method of ensuring sufficient power reserve in real time using measured irradiance and temperature is presented and validated against experimental data.