Modeling and Control of Multiple Flexible Loads in Demand Response Considering Renewable Energy Accommodation

With the development of renewable energy sources (RES), the safe and stable operation of the power system is facing a new challenge. Because of the intermittency and fluctuation of RES, more regulation resources are needed to alleviate the threat to the power system. Compared with traditional generation units, large-scale flexible loads at demand side can provide huge regulation potential for accommodating RES by demand response (DR), such as air conditioners (ACs), electric vehicles (EVs), energy storage systems (ESSs). The models of large-scale flexible loads are developed firstly, based on their operating characteristics, including individual loads and aggregated loads. Meanwhile, a control strategy is proposed to allocate the flexible loads reasonably according to different regulation targets, e.g. peak shaving and valley filling and suppressing the tie-line fluctuation, considering renewable energy accommodation. Finally, several cases are studied to show the performance of the control strategy, based on the real photovoltaic data. The results prove the efficiency of DR by large-scale flexible loads. The irregular fluctuations are reduced by 90 percent, and the peakvalley difference decreases from 457kW to 276kW, which are beneficial to the stable and economic operation of the power system. Besides, large-scale flexible loads can also provide operating reserve, about 4.3% loads of the peak power will be cut down during the power shortage period.