Cross-regional integrated transmission of wind power and pumped-storage hydropower considering the peak shaving demands of multiple power grids

Abstract

Due to the inherent uncertainty and intermittence of wind power, and the geographical mismatch between the wind power bases and the load demand, the problem of wind curtailment is becoming increasingly serious in China. To promote the consumption of wind power, this paper studies the short-term operation of a wind farm-pumped storage hydropower plant (WF-PSHP) hybrid system which transmits power to multiple cross-regional power grids through ultra-high-voltage (UHV) transmission lines. In this study, the forecasted error distribution of wind power is fitted using kernel density estimation. An optimization model that considers the peak shaving demands of receiving-end power grids (REPGs) is then established to determine the daily operation of the WF-PSHP system. The hydraulic constraints of the PSHP and individual unit operation constraints are also taken into account to make the model more accurate. To improve the solving efficiency, the original stochastic model is transformed into a deterministic mixed-integer linear programming (MILP) problem through several deterministic conversion and linearization techniques. The real-world case studies demonstrate that the integrated transmission of the WF and PSHP can reduce the peak-valley difference of the REPGs while absorbing large-scale wind power on different typical days in summer and winter.