Stability Analysis of Micropower Network.

Abstract

Stability analysis of micropower networks is gaining importance given the dwindling gap of power generation and demand as well as increasing penetration of intermittent renewable energy sources. Instead of using prevalent small-signal analysis-based approaches, with predictions typically limited to the vicinity of the equilibrium, the outlined approach provides a sense of global/semiglobal stability. With regard to the latter, current approaches to stability analysis are primarily based on time-domain-, energy-function-, and common-Lyapunov-function-based analyses. This paper outlines a stability analysis approach based on polynomial Lyapunov function, which is determined algorithmically using sum-of-squares optimization in order to maximize the region of attraction (ROA) of an equilibrium solution. This procedure precludes the need for prior knowledge of the form of the Lyapunov or energy function. In this paper, the tradeoff between accuracy of determining the ROA of a power-system model and the computation overhead incurred is evaluated.