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At present, most stochastic production simulation algorithms can not consider large-scale new energy, and there are many deficiencies in the stochastic production simulation algorithm including wind farm and photovoltaic power station. Based on the actual operation data of wind farm and photovoltaic power station, this paper analyzes the power generation characteristics of wind/photovoltaic power station from the Perspective of statistics. The extraction method of wind/photovoltaic power generation output scenario characteristic index, the principle and method of scenario screening and the evaluation index of confidence output capacity are proposed. On this basis, taking the lowest total generation cost or the best energy saving and emission reduction effect of power system as the optimization objective, a practical power system operation simulation model considering three different scenarios of power balance, electricity balance and peak shaving balance is established. The objective of the model is to minimize the total generation cost of the power system or to achieve the best effect of energy conservation and emission reduction. The simulation results show that the proposed system operation simulation model considering large-scale new energy can be effectively used for the research of wind power and photovoltaic power consumption capacity.

In this paper, a probabilistic load flow computation method based on the cumulants and Edgeworth expansion theory is put forward, and is used in the analysis of system containing wind farms composed of doubly-fed induction generator. Firstly a 2-parameter Weibull function is adopted to fit the random distribution of wind speed, and then the probabilistic model for wind power generator can be established based on active power output characteristic of wind power generator. Based on the linearized AC load flow model, analysis for IEEE 30-node system with wind farm is carried out. Finally the method is compared with Monte-Carlo simulation method, and the effects of wind farms integrated to the operation of power system is analysed in detail.

As an effective supplement to centralized renewable sources, distributed generation (DG) will be greatly developed in the future in China. The DG penetration rate is becoming higher and higher in power system distribution network in recent years. With the high proportion of DG, the power quality, protection and control of the distribution network will be affected. The impacts of DG from five aspects, such as power supply reliability, harmonic level, line loss rate, voltage qualification rate and short circuit current level are mainly studied in this paper. To quantitatively evaluate the impacts, an index system of the impacts of high penetrative DG is adopted, and the quantitative model and calculation method of each evaluation index are proposed. Furthermore, a comprehensive assessment model based on the combination of analytic hierarchy process (AHP) and entropy method is established in this paper to determine the weights of indices. Considering different penetration rates of DGs, the comprehensive evaluation model is calculated based on a test distribution system. The results are presented and analyzed to illustrate the usefulness of proposed model.