The Research Of Online Load Modeling Based On Statistical Synthesis Method

Power system consists of three parts: generators, transmission network and power load. In the current simulative calculation of power system, power generation and transmission model have been very perfect, but the load model has been often used in the relatively fixed form, such as constant resistance and motor model, which has hindered the accuracy progress of simulative calculation of power system. With the improvement of information technology and digital standards, the obtainment of detailed online load data has become possible. Under such background, this paper proposes an online load modeling in the method of statistical synthesis. The main in-novations of the paper have the following two points:First, the establishment of load model group for power system. Based on the in-dustry integrated load characteristic data from the offline collection, and the load compositive data from the EMS systems and Load Control System, load characteris-tics are comprehensively analyzed, load model established and load model group formed. Since the industry integrated load characteristics differ in different types of date or even different time in the same type of date, integrated load characteristics of the bus are various. Therefore, it is possible to establish different types of load models or the load models of the same type with different parameters. Meanwhile, the paper studies theoretically the operating characteristics of power system under abnormal circumstances and arrives at some integrated load models including some extreme cases. And all these load models form a model group, which requires characteristics of comprehensiveness and coverage.Second, the selection and release of load model. The selection of load model is in accordance with the needs of users and real-time integrated load characteristics.“The needs of users”refers that the users need different integrated load models of electric power system when they make different simulative calculations.“Real-time load characteristics”is concluded from the integration of the real time integrated load characteristics based on the online load data from the EMS systems and Load Control System and industry integrated load characteristic data from the offline collection. Load model can be selected as long as the needs of users and real time integrated load characteristics are available.It is concluded from the simulation results that the load modeling established via such a method fits the practical load characteristics better than the experiential one adopted in the current simulative calculation of power system, which proves the fea-sibility of the method.