Renmin Zhujiang (Jan 2024)
Short-term Optimal Scheduling Model for Hydropower Stations Considering Peak Shaving of Local and HVDC Receiving Power Grids
Abstract
In the face of the increasingly severe peak shaving pressure on both sending and receiving power grids of the high voltage direct current (HVDC) of large-scale hydropower stations,a short-term optimal scheduling model that takes into account peak shaving of local and HVDC receiving power grids of the cascade hydropower stations has been established.The model aims to minimize the maximum value of residual load in multiple power grids,not only considering the conventional hydraulic and power constraints of the cascade hydropower stations and the complex operation constraints of the HVDC transmission lines but also introducing coupled operation constraints between the HVDC transmission line and the hydropower stations.In the model-solving phase,the original model is transformed into a mixed-integer linear programming model by introducing auxiliary variables to linearize the objective function,hydraulic operation constraints,and HVDC operation constraints and using the big M method to linearize the bi-directional interval coupled constraints between the HVDC transmission line and the hydropower stations.Typical winter and summer days in a large-scale hydropower system in southwestern China are taken as examples,and the results show that the peak-valley difference of the sending power grid has decreased by up to 100%,while the decrease in the peak-valley difference in the receiving end power grid is 28.1% and 31.6%,respectively.It shows that the proposed model can share the flexibility of hydropower through HVDC transmission lines,achieve peak shaving in multiple power grids,and ensure safe operation of the HVDC transmission lines,which can provide a reference for short-term multi-grid peak shaving of large-scale cascade hydropower stations.
