Research On Dynamic Simulation Of Large-capacity Power Electronics Equipments

As the large-capacity power electronics equipments are used widely in power system, the voltage level and current level of the equipment are improving continually, and it is a big challenge for rapid development and performance testing. For these reasons, a model system with small-capacity and low voltage level is needed to simulate the dynamic and steady performance of the large-capacity equipments. This is the dynamic simulation technology, and now it is an important method to study the large-capacity power electronic equipment. This paper focuses on the design method of the dynamic simulation technology, and studies the affect of power electronic characteristics on simulation accuracy.This paper firstly studies the theory of similarity which is the basic of the dynamic simulation technology, analyzes the derivation, application merit and demerit of the three methods which are used to derive simular criterion. Based on the characteristics of power electronics devices in the process of development, this paper presents a new method to derive simular criterion, and uses this method to design the model system including PWM part, control part, filter part and sampling part. Aiming at the characteristics of the power electronic equipment, this paper analyzes the affect of delay, switch frequency and saturation voltage on imulation accuracy. It is verified by simulation in this paper, the design method of dynamic simulation system is effective and the analysis of the simulation accuracy is correct..At last, the cascaded H-Bridge STATCOM experimental prototypes are built including a small-capacity physical prototype and a largel-capacity HIL prototype. On the basis of the experimental prototype, the experiments have been carried out to verify the similarity of physical prototype and HIL prototype, and also verify the impact on the accuracy of dynamic simulation by the power electronics device features.