Research On Evaluation Index System Of Power Grid Planning Considering The Access Of Large-scale New Energy

With the substantial development of the power grid, and human’s attaching great importance to the renewable energy resources, more and more new energy is being switched into the power grid. Wind and solar energy are the most important two kinds of new energy. Because of their characteristics of randomness and volatility, the access of large-scale of new energy will have additional impacts on the power grid. It’s necessary to rebuild the evaluation indexes considering the access of large-scale new energy.In the first hand, we build the random output models for both of the wind farm and photovoltaic power station using Monte Carlo method. Then we establish the reliability model for the generation and transmission system which includes the wind farm and photovoltaic power station. The models of generators, transformers, transmission lines and relays are also established. It takes uncertainty of load forecasting into consideration in the load model. We introduce four new evaluation indexes based on the existing reliability indexes. They are the contribution coefficient of new energy for the expected energy not supplied, the contribution coefficient of new energy to the probability of load curtailments, the new energy capacity of credibility, and the bus voltage distribution index. We also introduce three new evaluation indexes for the economic indexes. They are the capacity of abandoned new energy, the saved cost of fuel and the saved cost of pollution emissions. We use the sequential Monte Carlo method to calculate the new reliability evaluation indexes and the stochastic production simulation method based on the effective capacity distribution to calculate the new economic evaluation indexes.Through the analysis of simulation examples we can know that the access of wind farm and photovoltaic power station to the power grid has a great impacts on the generation and transmission system. Accessing different capacity of new energy to the different bus will lead to different influences on the reliability and economy of power system. For this reason, when we choose the right solution we should refer to the actual situation and the structure of the network. These new evaluation indexes have a great reference value for the access of new energy.