Analysis of primary frequency regulation characteristics of PV power plant considering communication delay

Abstract

With the large-scale development of photovoltaic power generation, photovoltaic power plants (PVPP) are required to participate in primary frequency regulation to maintain the stability of the power system. Existing researches seldom consider the influence of the data communication delay of PVPP on the primary frequency regulation ability of PVPP. From the perspective of the communication system structure and control strategy of PVPP, this paper firstly analyzes the composition of the communication delay involved in the process of primary frequency regulation. Through the simulation of the three-machine nine-bus power system, the frequency regulation performance of PVPP under different time delays are analyzed. Furthermore, the influence mechanism of time delays on the primary frequency regulation results is discussed. Finally, two optimization schemes are proposed, which can reduce the communication delay and improve the tolerance of PVPP to the communication delay, respectively. The research results show that there are mainly two types of delays in the primary frequency regulation process of traditional large-scale PVPP. The longer the delays, the weaker the PVPP’s ability to participate in primary frequency regulation. In addition, the optimization of PVPP communication system and control strategy of inverters can help improve the frequency regulation ability of the PVPP, thereby maintaining the frequency stability of the power system.