Stochastic assessment and enhancement of voltage stability in multi carrier energy systems considering wind power

Abstract

Voltage instability is one of the main problems of power systems operation. Hence, voltage stability margin is kept within a sufficient range by several costly procedures such as load shedding. Coupling the electrical and natural gas systems by energy hub is a useful way to keep system voltage within a proper range following contingencies in the system. This paper proposes a new approach for assessment and enhancement of the power system voltage stability in the presence of wind power generation, as well as electrical and heat demands uncertainty. A stochastic programming method is adopted to handle the uncertainties of the wind power generation and demands. The proposed methodology shows that coupled operation of the electrical and gas systems in the presence of renewable resources can provide flexibility for the system along with a decrease in the operational cost in both regular cases and post-contingency conditions. In comparison with previous methods to enhance the power system voltage stability, in the proposed model the natural gas system could help power system to supply electrical demand without any voltage stability problem, where there is no load curtailment in some contingencies while in other cases, load curtailment is reduced dramatically which results in undeniable reduction of the total operation cost. Load margin is considered as voltage stability index, and the proposed framework is implemented on the IEEE 14-bus electrical system and 17-node natural gas system to indicate its applicability and appropriateness.