基于熵理论的电力系统最优潮流均衡度分析

摘要

现代电力系统呈现出多种复杂特性，加之新形势下电网互动运行成为热点，如何提高系统在众多复杂运行特性中的安全运行水平成为研究的重点和难点。针对此问题，提出基于熵理论的电力系统潮流均衡度分析方法，通过研究潮流变化特性，探索提高系统安全运行水平的新方法。首先，从负荷变化对系统潮流变化的影响机理出发，建立基于信息熵的潮流转移熵指标，描述系统支路潮流变化的均衡程度。进一步以潮流转移熵为目标函数建立电力系统最优潮流均衡度模型，优化系统运行方式，提高系统安全负荷裕度。在 IEEE 300节点系统下设置常规运行方式及源荷互动运行方式，通过算例分析验证了所述潮流转移熵指标及所建立最优潮流均衡度模型的有效性。算例同时表明，所述方法与直接以负荷裕度为目标的优化方法相比速度大为提高，为电力系统日内及日前发电计划的优化调整提供了参考。%With the great variety of complicated characteristics of modern power systems,plus the fact that power grid interactive operation has become a research hotspot in the new situation,improvement of safe operation of the system in the many kinds of complex operating characteristics has become the research focus and problem.Such being the case,a power flow balancing analyzing method based on the entropy theory is proposed.By studying the characteristics of power flow variation, new methods for system safe operation improvement are explored.By proceeding from the mechanism of influence of load variation on power flow,the power flow transfer entropy is established to describe the balance of branch power flow variation. On this basis,an optimal power flow balancing model is proposed with the power flow transfer entropy as the obj ective function.By generation rescheduling,the load security margin of power system could be improved.The conventional operation mode and source-load interactive operation mode are set in an IEEE 300-bus system case study.The results have validated the effectiveness of the power flow transfer entropy index and the optimal power flow balancing model under discussion. Additionally,compared with the optimization method with load margin as the obj ective direct,the method proposed has much higher efficiency,which provides a reference for daily scheduling and day-ahead scheduling in the power system.