Multi-time-scale coordinated optimal scheduling of integrated energy system considering frequency out-of-limit interval

As the physical carrier of the energy internet, the integrated energy system (IES) can coordinate and optimize the operation of various devices. In the day-ahead dispatching phase, considering the operation and maintenance cost of various devices and the interaction cost between IES and external network, in order to describe the influence of frequency fluctuation on the IES, the frequency over-limit penalty cost is introduced according to different frequency fluctuation range, and an economic dispatch model with the lowest operating cost of IES as the optimization objective is established, and the benefit of demand response (DR) on the economy of IES is analyzed. In the intra-day scheduling phase, considering the difference of scheduling time of various devices energy-consuming loads, a hierarchical rolling optimal scheduling model considering multi-time scales is proposed. The unit output is adjusted by sensing the changes of various loads and tie line plans in advance, and the model predictive control (MPC) optimization algorithm is used to solve the problem, which ensures the rationality of the day-ahead plan and the stability of the system operation. The results show that the strategy can give full play to the advantages of each equipment operation on the basis of both economy and robustness, and the economy of IES is obviously improved, which verifies the effectiveness of the model and algorithm proposed.

Automated summary

As the physical carrier of the energy internet, the integrated energy system (IES) can coordinate and optimize the operation of various devices. This study proposes an economic dispatch model and a hierarchical rolling optimal scheduling model for the day-ahead dispatching phase and the intra-day scheduling phase, respectively. By introducing frequency over-limit penalty cost and using model predictive control (MPC) optimization algorithm, the effectiveness of the models and algorithms are verified, while significantly improving the economy of the IES.