Evaluation of small signal stability of a power system

In reality, a power system is never in steady-state, as there are persistent fluctuations in load levels with associated adjustments in generation. The growing complexity of power systems, as well as the system exposition to various contingencies, have exacerbated the system's steady-state condition. Small disturbances that are always present in power system networks include small variations in loads, generation and switching operation of power system equipment. It is important to maintain the load-generation balance such that the system frequency remains nominal. Multiple severe contingencies with complex interaction would cause system instabilities, and thus deteriorate the system condition. This paper explores transient stability of a power system subjected to small disturbances using time domain analysis, eigen-values analysis, participation factors analysis, and transient security assessment using transient security index. Simulations have been conducted on the IEEE 14-bus system and the results presented.