Secondary Frequency Control Including Delay Compensation in Microgrids Based on Virtual Synchronous Generator
Chen Meng1, Xiao Xiangning1, Luo Chao2
1. State Key Laboratory of Alternate Electrical Power System With Renewable Energy Sources North China Electric Power University Beijing 102206 China; 2. Electric Power Research Institute, CSG Guangzhou 510663 China
Abstract:Virtual synchronous generators can provide the virtual inertia for the power network to improve the frequency stability. However, the delays in communication lines will deteriorate the performance of the traditional secondary frequency control. The whole small-signal model including secondary frequency control and communication delay was built and used to investigate the impacts of the virtual synchronous generator on microgrid stability. The effects of the important control parameters such as virtual inertia on the delay margin were discussed. In terms of the negative effects of the communication delay, a corresponding delay compensation strategy for virtual synchronous generator was proposed to compensate the impacts of communication delay, where a predicting loop was added to the control. The comparisons of simulation results in PSCAD/EMTDC on dynamics with and without the communication delay compensation were carried out. It is shown that the proposed control strategy can effectively improve robustness of the microgrid frequency control on the communication delay, and enhance the frequency stability.
陈萌, 肖湘宁, 罗超. 基于虚拟同步发电机的微电网延时补偿二次频率控制[J]. 电工技术学报, 2018, 33(16): 3845-3854.
Chen Meng, Xiao Xiangning, Luo Chao. Secondary Frequency Control Including Delay Compensation in Microgrids Based on Virtual Synchronous Generator. Transactions of China Electrotechnical Society, 2018, 33(16): 3845-3854.
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