| With the development of pulse power technology,the application conditions of pulse power switch as the hub of pulse power conversion are also subject to more stringent requirements,especially in the conditions of high pulse peak current and high current rate of change.MOS gate-controlled thyristor(MCT)is undoubtedly a better choice.The research object MCTs of this paper have both the high output impedance of MOSFET and the high current surge capability of thyristor.It is a kind of power switching device with great development prospects.However,with the continuous increase of pulse current requirements for pulse power technology applications,it is difficult for a single MCT device to meet the application requirements.At this time,parallel connection of MCT devices is undoubtedly a good solution.This article explores the problem of parallel current sharing of MCTs,finds the factors that affect parallel current sharing,and designs feasible methods to improve parallel current sharing and increase the current sharing of parallel current.The main contents of this article are as follows:1.Explore the issues that affect the parallel current sharing factors.Firstly,the theoretical modeling of the capacitor energy storage pulse power system is carried out.From the device and circuit aspects,the factors affecting the pulse current of a single device are explored,which lays the foundation for studying the factors that affect the parallel current sharing of MCTs.Secondly,through simulation analysis,the method,by controlling variables,is used to change the on-resistance,gate resistance and other factors of the device,and the device-circuit joint simulation is carried out to explore the factors that affect the current sharing characteristics.Finally,the factors that affect parallel current sharing are verified through experimental tests,and the results are compared with the simulation analysis results to draw conclusions.2.Improve the parallel current sharing method for design.First,investigate the current sharing method of IGBT,which can guide significance for the research of current sharing method of MCT device.Secondly,according to the pulse characteristics of MCT devices,a parallel current sharing strategy of MCT is proposed to improve the current unevenness in parallel.Finally,based on the method proposed in the previous article,simulation and experimental tests verify that the on-delay method can improve the current balance and the uniformity of parallel current.This method has a good effect on the current sharing problem caused by the device itself and the external circuit,and can greatly improve the current uniformity of the device.This method is simple and reliable,and has certain practical application significance. |
