磁瓦柔性成像新型LED光源热阻分析与计算

Analysis and Calculation of Thermal Resistance of a New Type of LED Light Source for Magnetic Shoe Flexible Imaging

在磁瓦表面缺陷检测新型LED光源的研制工作中,需要对光源进行热设计,以保证光源性能稳定可靠。通过构建LED光源热阻模型,分析降低热阻的有效措施,提出基于虚拟独立网格单元的LED光源散热计算方法。计算结果表明,光源散热量仅为LED耗散功率的14.69%,不能满足光源散热要求。通过将光源控制方法改进为触发控制,使光源平均输入功率降低为其耗散功率的1.2‰,从而保证光源的热稳定性。试验结果和光源实际工作性能验证该方法的正确性与可行性。

In the development of a new type of LED light source(LEDLS)for surface defect detection of magnetic shoe,thermal design is required to ensure stable and reliable performance of the light source.By constructing a thermal resistance model for the LEDLS,several effective measures to reduce thermal resistance were analyzed,and a heat dissipation calculation method for the LEDLS based on virtual independent grid units was proposed.The calculation result indicates that the heat dissipation of the LEDLS is only 14.69%of its dissipated power,which cannot meet the heat dissipation requirement of the light source.By changing the always-on control method of the light source to trigger control,the average input power of the light source was reduced to 1.2‰of its dissipated power to ensure the thermal stability of the light source.The experimental results and the actual working performance of the light source verify the correctness and feasibility of the method proposed in this paper.