Area Moment and Error Based Forecasting Difficulty and its Application in Inflow Forecasting Level Evaluation

As an important input of hydropower stations operation, the forecasted inflow provided by forecaster directly determines the power generation efficiency of hydropower stations. In order to promote the self-improvement of forecasters’ forecasting level through effective reward and punishment, it is necessary to determine a fair and reasonable comprehensive forecasting level evaluation method. In view of this, this paper puts forward the concept of forecasting difficulty, and classifies the external forecasting situations according to different rainfall conditions, different forecasting foresight periods and different inflow levels. Based on the physical meaning of forecasting difficulty, a new calculation method of forecasting difficulty using the error distribution and area moment is proposed in this paper, which can realize the forecasting difficulty calculation under different situations and different forecasting level standards. Coupling the forecasting difficulty coefficient with the forecasting level evaluation, a comprehensive forecasting level evaluation method of forecasters is proposed. The case study results show that, because the forecasting difficulty of different forecasting situations are considered in the proposed method, the higher the forecast accuracy of a forecaster in difficult situations (such as rainy situation), the higher his/her comprehensive forecast level. The result obtained by this method is fairer and more reasonable compared with the traditional method, which is of great significance to promote the forecasting level of forecasters in difficult situations.