电压稳定约束的最优潮流研究

针对电力系统将运行在更加接近电压稳定临界点的情况,建立了一种包含电压稳定约束的最优潮流(OPF)数学模型,在常规OPF模型基础上增加了一组电压稳定裕度约束作为不等式约束。引入能正确反映系统当前电压稳定程度的L指标函数作为电压稳定约束,通过调整该约束的上限值,可以获得系统所要求的电压稳定裕度。利用基于扰动KKT(Karush-Kuhn-Tucker)条件的原始-对偶内点算法对问题进行求解。多个IEEE测试系统上的仿真结果表明,该模型能较好地兼顾系统对电压安全性与经济性的要求;在电压稳定约束起作用时,发电总费用会随着系统对电压稳定要求的提高而增大;L指标约束的加入对系统的调节能力有一定影响;所用算法收敛性好、鲁棒性强,能有效地处理大量等式和不等式约束。

Study on optimal power flow with voltage stability constraints

As power system will operate more near voltage stability critical point,an OPF(Optimal Power Flow) model containing voltage stability constraints is established,which adds voltage stability margin constraints as the inequality constraints to the traditional model.By introducing the L index function,which correctly reflects current voltage stability of system,as the voltage stability constraints and adjusting their upper limits,the required voltage stability margin can be obtained.The primal-dual interior point method based on perturbed KKT(Karush-Kuhn-Tucker) condition is used to solve it.Simulation results on several IEEE test systems indicate the new model satisfies the demand of power systems for both security and economy;when voltage stability constraints work,the generation cost will increase along with the increasing voltage stability demand of system;the introduction of L index constraints has some effect on the regulation ability of system;and the algorithm can effectively deal with large quantities of equality and inequality constraints with good performance of convergence and robustness.