Frequency Control Ancillary Services in Power System with Integration of PV Generation

Abstract

The clean energy sources are the future of the power generation to fulfill the increasing electricity demand. The Renewable Energy Sources (RESs) are uncertain in nature; hence it is very challenging to integrate the RES in to the existing power system. These converter-based generators are not equipped with frequency control system. The conventional generators have automatic generation control for the primary and secondary frequency control purpose. The stored kinetic energy (KE) in the rotor of the generator provides inertial response at the disturbances. The RES already operating on the maximum power mode hence there is no accommodation of the active power for the primary and secondary frequency control. The rotating parts are absent in the inverter dominated system hence there is no room to provide inertial response. While considering this issue of absence of frequency control in converter-based system. There is need to approach for the frequency control ancillary services in RES integrated system to maintain the power system stability. This paper is basically focusing on the inertial response in addition with primary frequency control in RES integrated system. An inertial response control emulates the inertial power virtually through the energy stored in the DC-link. It improves frequency response and reduces the frequency nadir. For primary frequency control the external energy storage system is used to provide the additional active power to maintain the frequency at nominal value. To demonstrate this the simulation is done in MATLAB 2019a. The analysis of simulation results shows that, the frequency control in PV generation enhances the frequency stability.