基于实测响应轨迹稳定边界的电力系统暂态不稳定识别

Transient Instability Detection of Power System Based on Stable Boundary of Actual Measurement Response Trajectory

为充分利用广域测量系统WAMS(wide area measurement system)信息实现电力系统暂态稳定性快速在线识别,提出一种基于实测响应轨迹稳定边界的暂态不稳定识别方法.根据单机"位能脊"推导了单机-无穷大系统在相平面上的暂态稳定边界;证明单机无穷大系统任意比例剖分点处,由扰动能与电压相角构成的平面上的轨迹与相平面轨迹具有相似的几何特征,为间接利用发电机端口外网络测量信息识别电力系统暂态不稳定性提供了依据;证明了临界机组对的相轨迹上二阶导数等于零的点构成了系统的不返回边界,提出用临界机组对的相轨迹几何特征来识别系统暂态稳定性.为避免判据在线应用时受参数及不确定性干扰可能造成误判,对判据进行了实用性改进.利用PSASP 6.28 WEPRI 36节点仿真算例验证了所提判据的有效性.

In order to make full use of the information of wide area measurement system （WAMS） to rapidly identify the transient instability online, this study proposed a transient instability detection method based on stable boundary of actual measured response trajectory. The authors deduced the transient stable boundary condition on the phase portrait of OMIB system according to the ridge of one machine infinite bus （OMIB） system. It is found that the trajectory of disturbance energy versus voltage phase angle is geometrically similar with the phase trajectory at arbitrary point of OMIB system. The measured information outside generator bus can be used for identifying transient instability. Meanwhile, the points with zero second derivative form a no-returning boundary on the phase trajectory of critical unit pair, which shows that the geometrical feature can be used for identifying the transient stability. The authors also gave a checkout of the availability by the simulation test of PSASP6.28 WEPRI 36 bus system.