结合直流潮流模型的电网断面热稳定极限快速评估方法

电网结构的增强使得系统的热稳定问题日益突出。采用直流潮流的方法对典型等值系统的断面热稳定极限进行了推导,分析了断面设备N-1开断对在运设备有功潮流变化的影响。基于有功潮流的阻抗分配原理,提出了对断面热稳定极限的评估方法和流程,可实现断面热稳定极限和限制故障的快速评估。最后,以河南电网2014年夏季大负荷方式为例,对豫北断面的热稳定极限进行了评估,仿真结果证明了所提方法的可行性。

Fast evaluation method on thermal stability limit of power grid cross-section with DC power flow model

Enhanced grid structure makes the system thermal stability problems increasingly prominent. The thermal stability of grid section is deduced by use of DC power flow method in typical equivalent system, furthermore, the effect of section N-1 breaking on active power flow in operating equipment is analyzed. Based on the principle of active power flow distribution to meet the impedance proportional relationship, thermal stability limit section assessment methods and processes are presented, which can achieve fast assessment on thermal stability limits and restriction faults. Finally, the summer maximum loads mode of Henan power grid in 2014 is taken as example, and the thermal stability limit in northern sections is evaluated. The simulation results prove the feasibility of the proposed method.