121 / 2021-06-15 20:57:15

MODELING OF LUMPED CHARGE MODEL OF IGCT DEVICES IN HYBRID DC CIRCUIT BREAKERS

Hybrid DC circuit breakers are the guarantee of reliable power supply in DC transmission. In the actual application of hybrid DC circuit breakers, power electronic devices are extremely susceptible to shocks during operation, which can cause damage to the devices and ultimately lead to failure of the circuit breaker to break, which has a serious impact on the entire system. Therefore, in order to avoid unnecessary damage, considering the economic cost and the stability of the system, it is very necessary to perform accurate simulation of power electronic devices. At present, IGCT devices are widely used in hybrid DC circuit breaker power electronic components due to their superior cost performance, high surge current resistance, and low conduction loss. IGCT device models are mainly divided into functional models based on external characteristics and physical models based on internal carrier operating mechanisms. Since the functional model is usually modeled by the fitting method, the accuracy is low, so it is not considered. In this paper, the IGCT device modeling is completed by studying the lumped charge model based on the internal carrier operating mechanism. This method can simulate the distribution of carriers, currents and electric fields in various regions within the IGCT, and can simulate the internal operating mechanism of the IGCT. The charge storage nodes and the charge connection nodes in each area are connected to solve the problem, and the charge distribution and transmission between the lumped charge nodes in the device are described, and the accuracy and operability of the calculation are taken into account. Finally, the simulation results are compared with actual tests to further verify the accuracy of the model. Through the above research, a precise IGCT device model is provided for future hybrid DC circuit breakers, which is of great significance to the development of hybrid DC circuit breakers and the development of scientific research.