Transient thermal network model for train‐induced wind cooling dry‐type on‐board traction transformer in electric multiple units

Thermal characteristic is one of the key performances dry-type on-board traction transformer (D-OBTT), which directly affects operation safety new generation electric multiple units. However, due to particularity train-induced wind cooling mode D-OBTT, existing efficient thermal modelling methods cannot be used under fluctuating air velocity and load. A time-saving transient model for D-OBTT proposed. First, framework network (TTNM) proposed considering coexistence non-fully fully developed state addition heat flow in solid domain. Then, a novel formula calculating length section geometric dimensions flux density based on computational fluid dynamics (CFD) parametric sweeps first time. The accuracy TTNM validated by experimental setup, time consumption significantly reduced compared with CFD.