Thermal management in industrial product development
by N.J. Eggink
Central Development Lighting, Philips Lighting B.V., Eindhoven, The Netherlands
Abstract
The thermal management of lighting electronics is for a great deal supported by simulation tools.
Results strongly depend amongst others on the component models, the modelling of radiation heat
transport and the value of the component heat production. This paper gives a survey of how these topics
are dealt with in a product engineering environment and the directions for improvement.
1, Introduction
In the lighting world electronic devices for powering and regulating lamps, so called electronic ballasts, are build in compact housings. The small housing dimensions lead to relatively high thermal loading of the components. It is the job of the designer to make product designs, which satisfy temperature and lifetime demands. In recent years Philips Lighting has gathered experience with the possibilities and problems of thermal simulations. This has resulted in the creation of improved component models, a method to deal with radiation transport within the simulation package Flotherm and a possible method to determine
component heat production. These items are necessary parts of the thermal design process and their application is illustrated with practical examples of electronic ballasts.
2. Simplified component models
Due to the relatively small number of electronic components in electronic ballasts,simulation models are made on component level. In first instance components were modelled as single blocks without detail, only the body and the lead were modelled. However, it was found that this approach is not good enough. For instance, when modelling a coil as a single block, the lack of detail makes it impossible to obtain temperatures of coil-windings and ferrite core. Also, when a component is in contact with a heatsink, the calculated component temperatures are too low. Improvement of component models is achieved by developing so
called "simplified" models.作者: NMB 时间: 2011-3-7 23:48