Full-Order Observer Based IGBT Temperature Online Estimation

An online temperature estimation method is presented, based on a full-order state observer. To ensure the accuracy of the developed model, FEA (Finite Element Analysis) method is applied into deriving a Cauer type thermal network where the observer is modelled on. The developed observer enables estimation of temperatures at any reliability critical locations only measuring one accessible location. As the observer includes all of system dynamic information, it can estimate high dynamic temperature with a lower dynamic temperature sensor. The proposed temperature estimation method is verified experimentally. Although the experiment is developed for a specific IGBT, the proposed strategy is of general validity for multilayer-structure devices.