Research on multi-objective optimal joint dispatching of wind-thermal-hydro power in multi time scales

A multi-objective optimal joint dispatching model in multi time scales is proposed in this paper, taking into account comprehensive factors in the model, including different time scale features of wind/water resource, electrical/heat load characteristics, peak-load regulation capability, thermo-electric coupling characteristics of different thermal units, transmission capacity and system spinning reserve requirement. Furthermore, detailed formulations are developed for various kinds of thermal power units and hydro power units in the integrated energy system. Based on these developed formulations, a combination of multi time-scale schedule method and wind power forecasting technology is proposed. The day-ahead schedule is established on the short-term forecasting technology to optimize unit commitment of thermal power generators for minimizing operation costs together with maximizing ability of accommodating wind power. The intraday schedule is established to optimize power generation plan for all thermal power generating units, hydroelectric generating sets and wind power plants, on the basis of ultra-short-term wind power forecasting technology. At last, the power generation plan can be timely revised according to on-line schedule, which will largely reduce the gap between actual output and intraday schedule and to ease the burden of AGC units, thereby ensuring real-time scheduling of the active balance. The paper concludes with simulations conducted on a real provincial integrated energy system in China. Simulation results have validated the proposed model and corresponding solving algorithms‥