考虑电压稳定约束的最优潮流

采用指数负荷模型研究了有载调压变压器对系统最优潮流的影响。在阐述电压稳定性L指标的基础上,将L指标引入传统最优潮流中形成电压稳定约束的最优潮流,运用原-对偶内点法求解该模型。算例结果表明,该模型鲁棒性较好,能更加真实地反映系统实际运行情况。不同静态负荷模型对系统电压稳定性和经济性有一定的影响,系统电压稳定性的提高是以牺牲经济性为代价的,在考虑电压稳定性时,有载调压变压器的加入可以有效降低系统燃料费用,平抑系统有功出力和燃料费用的波动,将波动维持在一个较小的范围内。

Optimal Power Flow Considering Voltage Stability Constraints

By use of more precise exponential load model,the effect of on-load tap-changing transformer(OLTC)on optimal power flow(OPF)is analyzed.After expounding the L-index of voltage stability,this index is led into traditional OPF to form voltage stability constrained optimal power flow(VSCOPF),and primal-dual interior point method is used to solve this model.Applying this model to IEEE 30-bus system,obtained results show that the proposed model possesses better robustness and can reflect actual operation conditions of power system more factually.Different static load models greatly influence both voltage stability and economy of power system and the improvement of system voltage stability is at the expense of system economy.When voltage stability is taken into account,application of OLTC can effectively reduce the fuel cost of the system,abate the fluctuation of both active power output and fuel cost and confine the fluctuation in a smaller range.