Isolated Grid Unit Commitment with Dynamic Frequency Constraint Considering Photovoltaic Power Plants Participating in Frequency Regulation
Ye Jing;Lin Tao;Zhang Lei;Bi Ruyu;Xu Xialing;School of Electrical Engineering Wuhan University;Collabrative Innovation Center for High-Efficient of Solar Energy;School of Electrical and Electronic Engineering Huazhong University of Science and Technology;Central China Electric Power Dispatching and Communication Centre;
Isolated grid(IG) usually has small inertia constant and limited ability of primary frequency regulation. In addition, high penetration level of photovoltaic power plants(PV-PPS) integrated to IG will deteriorate system inertia and primary frequency regulation ability. To ensure the stability of frequency, unit commitment(UC) model considering dynamic frequency limit(DFL) was proposed in this paper, and PV-PPS were deloaded to participate in frequency regulation. Based on frequency response model with PV-PPS participating in frequency regulation, the expression of required minimum frequency regulation capacity of PV-PPS was deduced, which guided PV-PPS retain sufficient but not excessive capacity. Then, taken DFL into consideration, a UC model with frequency regulation capacity of PV-PPS was proposed. In order to avoid complex solving procedure, the optimization cut and benders cut were used for eliminating frequency limit/regulation capacity violations in iteration method. The results indicate that security and economy can be achieved by the proposed scheme.