Comparison of Model Order Reduction and Thermal Network Approaches in the Extraction of Dynamic Compact Thermal Models of LEDs

The Delphi4LED project is identifying methodologies for the extraction of multi-domain, electro-opto-thermal compact models of LED packages. The temperature dependent opto-electro model provides the thermal model with a thermal power dissipation, the thermal model provides the opto-electro model with a junction temperature. Together they are co-simulated to convergence whereupon both thermal and optical behaviour is predicted. Such models would be used by lighting designers to provide rapid indication of the performance of a proposed luminaire design. The thermal portion of the multi-domain model is required at least to provide temperature prediction of the chip junction and potentially phosphor and solder connection point temperatures. Equivalent thermal networks or reduced order models are both candidate approaches for the thermal model. This study will detail the extraction process for both, compare their performance and accuracy and discuss pros and cons regarding their possible adoption.