Electro-thermal modelling of three phase inverter

This paper introduces an electro-thermal model of an inverter implemented in PLECS. This model is able to calculate IGBT junction temperature with a mission profile. Look up tables (LUT) of switching power loss are generated by running physics-based IGBT and diode models under different operating conditions. The inverter model interpolates power dissipation from the LUTs to speed up the simulation rather than running the physics-based device model, which is relatively slow. The thermal network is extracted from the heating curves of IGBT junction and case temperature which are measured on a power cycling rig. Junction temperature under operating condition is obtained with the power dissipation and thermal network. Although the work presented here is general applicable to any converter applications, our particular emphasis in this paper is on renewable energy system such as wind power applications. This model extends the current available inverter model which is fixed frequency and voltage to various frequency and voltage which is more closely aligned with the operation of wind turbine.