POWER CONVERSION UNIT, AUXILIARY LOCOMOTIVE POWER SUPPLY CURRENT CONVERSION CIRCUIT, AND LOCOMOTIVE

摘要

Provided are a power conversion unit (10), an auxiliary locomotive power supply current conversion circuit, and a locomotive. The power conversion unit (10) comprises: at least three groups of power conversion sub-units (13), a support capacitor group (11) and a protection circuit (12), wherein the at least three groups of power conversion sub-units (13) are used for converting a direct current into a three-phase alternating current, and comprise double-tube IGBTs (131) and drive circuits (DBR, DBS, DBT). The double-tube IGBTs (131) have high junction temperatures, and two input ends of the double-tube IGBTs (131) are respectively connected to an external positive and negative two-layer laminated busbar (DC+, DC-), and three output ends of the double-tube IGBTs (131) are respectively connected to an RST three-phase output laminated busbar. The drive circuits (DBR, DBS, DBT) are connected to a control unit, and the drive circuits (DBR, DBS, DBT) are used for controlling the switching on and switching off of the double-tube IGBTs (131). The support capacitor group (11) is applicable to a high-temperature environment and is used for supporting a direct-current circuit voltage. The protection circuit (12) is used for protecting the other components in the power conversion unit (10). The double-tube IGBTs (131), the support capacitor group (11) and the protection circuit (12) are connected to each other in parallel. According to the power conversion unit (10), the service life of the power conversion unit (10) in a high-temperature environment can be prolonged.