Device and method for limiting junction temperature and reducing loss of traction converter switching device

Abstract

The invention relates to a device and a method for limiting the junction temperature and reducing loss of a traction converter switching device. The device comprises a power module, a DSP and a CPLD.The method comprises the following steps: S1, the DSP collects a three-phase output current signal and a radiator temperature signal, and the CPLD calculates the switching frequency of an IGBT; S2, the DSP calculates the collector current in the conduction process of the IGBT according to the three-phase output current signal, and calculates the on-state loss and switching loss according to the collector current; S3, the DSP calculates the heating power of the IGBT according to the on-state loss and the switching loss; S4, the calculated heating power is imported into a thermal resistance model so as to obtain real-time junction temperature data of the IGBT; and S5, if the junction temperature data is higher than a set threshold, the switching frequency of the IGBT is controlled through the CPLD, and thus, the switching frequency of the IGBT is reduced. Therefore, loss is reduced, and the maximum junction temperature of the IGBT is limited.

Description

technical field [0001] The invention relates to the field of railway trains, in particular to a device and method for limiting junction temperature and reducing losses of switching devices of train traction converters. Background technique [0002] Railway transportation plays an indispensable role in the development process of our country. Promoting the development of my country's railways in the direction of informatization and intelligence has become an important development factor for the current railway construction. As an important part of the train transmission system, the traction converter of the train has a high proportion of faults due to its core component, the IGBT, which is relatively delicate and fragile. The IGBT failure is closely related to its excessive heating power and high junction temperature. Most of the IGBT failures are caused by the excessive heating power and high junction temperature of the IGBT. Therefore, it is necessary to monitor the heating...

AI Technical Summary

Problems solved by technology

However, there are still many problems in the monitoring of IGBT heating power in train traction converters. At the same time, the existing monitoring methods cannot achieve the purpose of limiting the maximum junction temperature of IGBT while monitoring IGBT heating power.

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