Multi-objective Optimization For DG Planning Based On Multi-scenario Analysis

As the power industry and energy industry develop rapidly, renewable energy-orienteddistributed generation technology has been widespread concerned, distributed generationsbecome necessary complementarity of electricity supply in distribution network. Distributedgenerations which are connected to the grid would have an impact on reliability, powerquality and stability of distribution network, so the reasonable choice of location and capacitycan make distributed generation play a greater efficiency in distribution network. Solarradiation intensity and wind speed have great randomness because it may be affected byseasons, weather, geographic positions and so on, so distributed generations which arerepresented by photovoltaic and wind power generation exist volatility and uncertainty;different types of electricity load exist volatility and uncertainty as well because of somefactors like the habits of different seasons and the economic development. The conventionaldistributed power planning methods take no account of the volatility and uncertainty ofdistributed generations’ output and load demand, they will lead to the plan be too conservativeand the plan of location and capacity be unreasonable.The problems existing in the distribution generations planning are considered in thisthesis, the thesis will study on the planning problems of distribution generations from a newview, the process is as follows: Firstly, introduce the principle, characteristics, the outputmodel and connection modes of typical distribution generations, and then introduce theinfluence and challenge which is brought by distribution generations connected to the grid,and analyze the effects on line loss and voltage distribution before and after distributiongenerations access to the grid though example simulation; Secondly, introduce the methodthat simulate the uncertainty of random variables in the actual environment, namely scenarioanalytical method based on timing characteristics, and then the distributed generations’ outputand load demand’s timing characteristics and multi-scenario analytical method are introduceddetailedly in this thesis; Thirdly, with objectives of annual life cycle yield rate, voltage profileimprovement rate and network loss rate, distribution generations planning models of economy,voltage quality and network loss are built in this thesis, and introduce multi-scenario which isproduced by scenario analytical method based on timing characteristics into themulti-objective planning models, in order to take a full consideration to the volatility and uncertainty of generations and load, and make planning more rationality. Finally, amulti-objective compound differential evolution algorithm was used to solve the problem, andthe method based on the shortest normalized distance was used to realize the overall optimalsolutions’decision-making.Finally, results of distributed generations multi-objective planning for the IEEE-33nodetest feeder demonstrated the validity and superiority of the proposed approach. The researchcan provide a new thought for the modeling, optimal control and optimization algorithm ofdistributed generations planning in distribution network, which has important theoreticalsignificance and academic value; meanwhile, it can provide certain theoretical basis fordistributed generations planning in future.