Research On The Problem Of Alternative Capacity Allocation Under The New Situation

Operating reserve is an essential technical means to ensure secure and economical operation of power system. In our country, the pattern of power net-works interconnection, ultra high voltage ac and dc transmission, long-distance and large-capacity transmission have formed. The access of large scale new energy, commission of large-capacity UHVAC and UHVDC transmission channel give prominence to the uncertainty of network operating mode, at the same time, affected by the energy-saving and emission-reduction, reliability of power supply, the method of reserve configuration is facing new challenge, on the other hand, demand side response(especially electric vehicle) provide a new measure for reserve configuration.Reserve configuration problem under new situation is studied in this paper, the research work focus on the following aspects:(1) Research on optimization method of reserve considering wind power based on cost-benefit. Considering the uncertain factors, such as the load, wind forecast errors, and the fault outage of generators, the power system reliability with the integration of wind power is evaluated based on Monte Carlo. Taking minimized generation cost of power grid, reserve cost and outage cost as objective, the model and flow of optimal reserve considering wind power based on cost-benefit is established. Simulation has been done to verify the rationality of proposed method.(2) Study on the influence of electric vehicle charging and discharging on reserve configuration. Considering the effect of electric vehicle’s charging in different periods of time and discharge characteristics on load curve, the simulation model of electric vehicle’s charging/discharging behaviors is established, the effect of electric vehicle paralleling in the grid on system reliability and generation-side reserve is studied. The simulation example shows that the discharge characteristics of electric vehicle can improve system reliability, the vehicle-to-grid(V2G) reserve can reduce generation-side reserve and is economically feasible.(3) Research on reserve sharing and invocation of interconnected power systems. Firstly, considering reserve sharing can realize power support under fault conditions, taking practical system as example, the reserve sharing case is analyzed. Then, reserve invocation in primary frequency control under dc fault is studied in this paper, also the constraint of interface power flow on reserve invocation is studied by using power flow simulation and transient simulation. At last, the influence of various regions’ reserve distribution on reserve invocation is analyzed in this paper. The results show that:reserve sharing can ensure system stable, reasonable distribution and invocation of reserve can ensure secure and economic operation of system.