Power system contingency is an operational state that can happen as a result of a system discontinuity and results in overall system voltage instability. The system has seen intermittent power outages in previous years, according to Ethiopia Electric Power. Parts of the grid system were disrupted during the event, and as a result, there was a partial blackout of the system. Therefore, research proposes identifying the system's exposure to lessen the likelihood of such accidents happening. The proposed method demonstrated on 15 bus system Northwest region of Ethiopia Electrical Power Network using DigSILENT software. System’s exposure was evaluated by using the voltage performance index and the overload performance index. The indices enable the evaluation of two distinct system stress signs, including voltage instability and overloads. Performance index data show that the BDII230 bus to the GoII bus line has highest performance index value (4.9488) from other for N-1 line outage circumstances. This indicates that BDII230 bus to the GoII is most dangerous line for interruption of Northwest region of Ethiopian Electric Power network. But the most sensitive bus for voltage limit violations on this condition are Gondar load bus and Metema load bus. Their voltage profile is 0.908 and 0.923 per unit, respectively. Also, for 50% load demand increasing conditions, Gondar load bus has highest performance index value (20.2352) compared to the other load buses and its voltage profile is 0.8879 per unit. So, applying performance index for Northwest region of Ethiopia Electric Power network is used to know the system performance such as voltage instability and overloading, for forecasting future operation and expansion planning of this area.

电力系统意外事件是由于系统不连续性而可能发生的一种运行状态，并导致整个系统电压不稳定。据埃塞俄比亚电力公司称，该系统在前几年曾出现过间歇性断电。事件期间部分电网系统受到干扰，导致系统部分停电。因此，研究建议确定系统的暴露程度，以减少发生此类事故的可能性。该方法使用 DigSILENT 软件在埃塞俄比亚西北地区的 15 个总线系统上进行了演示。采用电压性能指标和过载性能指标评价系统的暴露程度。这些指数能够评估两种不同的系统应力迹象，包括电压不稳定和过载。性能指标数据显示，在N-1条线路停运的情况下，BDII230总线至GoII总线线路具有最高的性能指标值（4.9488 ）。这表明通往GoII的BDII230公交车是埃塞俄比亚西北地区电网中断的最危险线路。但在这种情况下，对电压限制违规最敏感的总线是 Gondar 负载总线和 Metema 负载总线。它们的电压分布分别为每单位 0.908 和 0.923。此外，在负载需求增加 50% 的情况下，与其他负载总线相比，Gondar 负载总线具有最高的性能指数值 ( 20.2352 )，其电压分布为每单位 0.8879。因此，应用埃塞俄比亚电网西北地区的性能指标来了解电压不稳定和过载等系统性能，以预测该地区未来的运行和扩展规划。