The Methods And Case Studies Of Long Term Electricity Load Synthetic Forecasting

The long term power load forecasting is the basement of city power network planning. Not only does it provide necessary data base for power network planning, but also relate to the developing and planning of the power network entire system. Doing long term power load forecasting to electric load scientifically and accurately can provide feasible data base for updating electric units and choosing new power generators. And it also can reasonably allocate the plans about the running and maintenance of generators. All of this can also assure the well function of social activities, energy saving, and lowering of operating cost. It is the premise of that ensure power system can run in the safe and economic way.From the character of long term power load forecasting and based on the relative merits of single forecasting and combined forecasting method, the essay takes combined forecasting method as the long term power load forecasting model. To improve the accuracy of combined forecasting, the combined forecasting model based on grey relation analysis is established. The theory of this model is:Several accurate single forecasting models are chosen through grey relation analysis, and the main body of the combined forecasting model is formed. Then, after the weight coefficient is gotten through least squares of the error, the combined forecasting model can be set up.At last, with the combined forecasting model based on grey relation analysis, from the character of power load in Tangshan, its long term power load is forecasted. The results show that, the accuracy of combined forecasting is higher than that of single forecasting and the combined forecasting model based on grey relation analysis is scientific and feasible.