Evaluating thermal management efficiency in converters

Design Techniques for Thermal Management in Switch Mode Converters

“…In order to assess improvements in switch mode converters' thermal management brought about by these integration methods among others, figures of merit are invaluable. First, they quantify the effective use of material used in a thermal-management function in order to optimize all available volume in a converter, and, second, they quantify how well the thermal management achieves its goal of keeping all individual components, not only at a safe but also at an optimal operating temperature [11], [12]. Optimal temperatures can be defined differently for set objectives such as reliability or high power density.…”

“…A converter with all the power components operating at exactly its optimal value will have a TDR ws and TDR band of one, which is the asymptotic ideal value. An example of the TDR method is shown in [11] and will further be exemplified in the case study that follows. The case study will incorporate the technologies discussed until now and use the derived figure-of-merit system as design guideline.…”

“…A case study illustrating the integration approaches discussed in Section I and the thermal-management figures of merit illustrated in Section II is performed on an isolated 20 W Flyback topology, similar to the case study of different converters performed in [11]. To determine the figure of merit for thermal effectiveness, the components need to be grouped in categories, each with their own set of maximum and optimum temperature values, according to Section II-B.…”

Design Towards Higher Integration Levels in Power Electronics

“…The two thermal management performance indicators indicate the per volume heat which a converters thermal management is submitted to, as well as the thermal performance of the components together with their margin for improvement [11]. 1) Thermal management loss density (TMLD): quantifies the effective use of implemented material and parts that perform a thermal management function.…”

“…It assesses the level of thermal loading of material and subsequently comments on the level of power density attainable in electronic assemblies. Similar to power density, the thermal management loss density relates power to volume, where P losses is the dissipated electrical loss (heat) and V T M the volume invested in thermal management [11]. It is defined as the ratio between the electrical losses that need to be removed from a system and the volume of the thermal management material that needs to transport the heat caused by these losses and is given by…”