含VSC-HVDC的暂态稳定约束最优潮流

Transient Stability Constrained Optimal Power Flow Considering of VSC-HVDC Integration

提出运用轨迹灵敏度法将含电压源换流器的高压直流(voltage source converter-high voltage direct current,VSC-HVDC)输电的暂态稳定约束最优潮流问题转化为含VSC-HVDC最优潮流和含VSC-HVDC暂态稳定2个子问题,避免直接求解混杂系统暂态稳定约束最优潮流所带来的困难。根据暂态稳定计算结果,求出连续系统状态量相对于发电机机械输入功率的轨迹灵敏度,据此求取最领先机和最落后机之间转移的有功功率,修改最优潮流有功出力的上下限,从而实现2个子问题的交替求解。在求得的转移功率满足系统暂态稳定约束后,通过二分法求得系统的最优转移功率。以IEEE39节点系统为算例,验证了轨迹灵敏度法对于求解含VSC-HVDC的暂态稳定约束最优潮流的有效性和合理性,算法实现简单,可处理多个预想故障。

The paper provides a method using trajectory sensitivity to divide transient stability constrained optimal power flow （TSCOPF） considering integration of voltage source converter-high voltage direct current （VSC-HVDC） into two sub-problems, which were optimal power flow （OPF） and transient stability both under consideration of integration of VSC-HVDC, and difficulties of solving TSCOPF directly with the mixed system were avoided. According to the results of transient stability calculation, trajectory sensitivities of continuous system state variables with respect to mechanical power of generators were calculated, then the shifted active power between the most advanced generator and the least advanced generator was computed, the upper and lower active power limits of the OPF were modified, and thus the two sub-problems can be solved iteratively. After the shifted active power met the transient stability constraints, the optimal shifted active power was searched with dichotomy. The effectiveness and rationality of the method using trajectory sensitivity to solve TSCOPF considering integration of VSC-HVDC are verified by an IEEE 39-bus system, the method is easy to be realized and can deal with multi-contingencies.