Distribution System Reliability Evaluation Based On Demand Response And Demand Dispatch

The rapid development of modern power system has caused the dramatically increasing on consumers’ power consumption together with the need for higher level of power system reliability. At present, to alleviate the pressure of using electricity, demand side management research has been taken attention by experts of many countries. The implementation of demand side management improves the use ratio of distributed power supply based on renewable energy. Besides, the demand side management technology also has a positive impact on distribution system reliability by leading electricity consumers not to use electricity when the system load reach the peak time by formulating appropriate price mechanism. It is necessary to assess distribution system reliability considering demand side management technology as the distribution system reliability has a direct affect on electricity consumers’ satisfaction, especially for agriculture production, industrial and commercial management and residential life.A distribution system reliability evaluation algorithm considering demand response was set up in this paper firstly. First of all, a load optimization model based on time-of-use pricing was set up, including three steps: the division TOU periods, the determination of price elasticity coefficient and a model calculating the variable of electricity consumption. Based on the above research, establish the load optimization model targeting minimizing the peak load and load range, the constraint conditions considers operation and power market constrains; Secondly, making the optimal classification based on dichotomy; Finally, evaluating the distribution system reliability on each load level and weighted average the reliability index according to the duration of each load level. Due to the implementation of demand response in distribution system, it is need to introduced real-time correction of load. Evaluating the results, make a detailed analysis about the impact of demand response on distribution system.A new definition called demand dispatch was determined to improve the passivity of the traditional demand response and a new distribution system reliability evaluation algorithm was set up to assess the impact of demand dispatch on distribution system.First of all, based on a sequential probabilistic model of wind generators, a piecewise of distributed generation output was set up together with a charging/discharging management model of energy storage devices. Then, a demand dispatch model based on piecewise was set up to consider the change trend of load based on piecewise. Finally,bringing the real-time correction load and load failure rate into the traditional Monte-Carlo simulation method to evaluated the impact of demand dispatch on distribution system reliability evaluation.The validity of above model and the method are studied through numerical tests on modified IEEE RBTS BUS6 test system. As the result shows, demand response and demand dispatch do have an positive impact on distribution system reliability.