Self-healing model for gas-electricity distribution network with consideration of various types of generation units and demand response capability

Abstract

In this study, a model has been proposed to carry out Self-Healing (SH) in distribution level with consideration of combined gas and electrical network and with consideration of various generation types include Micro-Turbines (MTs), Energy Storages (ESs) and Combined Heat and Power (CHP) units. The model also determines the optimum generation amounts of all generation units with target of minimizing of total cost. It is to be noted that the supplying source of gas demands through CHP or directly from natural gas network are important in defining of the optimum amount of the generation units. In case of fault occurrence in the grid and outage of line/lines or zone/zones as a result, the model determines the new grid topology so that it will not violate the constraints of the gas and electric networks and the minimum amount of loads will be isolated from the grid. Hence, the new generation amounts of generation units will be determined based on the new topology of the grid. If the generation amount or ramp rate limit of generation units are not enough or the transfer capacity of lines reach to their limitation the model will take action for Demand Response (DR) for controllable loads and in critical cases zone/zones-shedding to reduce total demand of the grid. The proposed model, after linearization, would be as Mixed Integer Linear Programming (MILP) problem that is solved by commercial solver. It is implemented on a grid with six Microgrids (MGs) and also 44-node system for testing and verifying.