脉冲强化热电制冷的瞬态热-电输运协同机制及能量转换分配机理

For the continuous miniaturization and high heat flow density of high power electronics, the bottleneck of interfacial thermal management is universal in the coupled heat transfer process, especially a challenging task for exploring the general characteristics of the interaction of multi-physical effects in the micro-scale heat transfer process. As a potentially efficient direct cooling technology, there has been a considerable resurgence of interest for the all-solid-state thermoelectric cooling technology in cooling the active regions of high heat flux pulsed with supercooling. From the view of cross disciplinarity (referred to Semiconductor physics of solids, Materials and Interface science, and control theory), as well as combined with Pulse Width Modulation (PWM) experimentation and a model correction method with adaptive logic identification theory, research purpose is to develop a pulse driven thermoelectric cooling prototype and performance monitoring platform. Then, it can put forward the new mechanism on the transient thermo-electric transport property and energy conversion-allocation, and explore the structural optimization approach matched with the pulse pattern, together with the optimum pulse driving mode and control strategy for the efficient interface cooling performancet, which cover from macroscopic components to microscopic energy transport medium (hole to electronic charge carriers). It is expected to provide the corresponding theory and method for promoting the thermal management of high density packaging field to gradually change from empirical design to system simulating optimization.

大功率器件封装微型化及其高热流密度界面的“散热瓶颈”问题是目前耦合传热过程关注解决的焦点，尤其在微尺度条件下准确诠释多物理效应交叉作用的共性问题极具挑战。脉冲强化热电制冷作为极具潜力的高效界面直接冷却技术有了新的发展契机。研究内容从半导体固体物理学、材料与界面科学、控制论的学科交叉角度出发，结合多模态脉宽模式输出（PWM）实验法和自适应逻辑辨识模型修正法，从宏观器件向微观能量输运介质（空穴-电子载流子对）入手，目标为开发出一套能计量及评价热-电转换过程中各能量输运指标的脉冲式热电制冷装置及其性能监测平台，以进一步探索脉冲强化热电制冷的瞬态热-电输运性能协同调控机制及其能量转换分配机理、寻求与脉冲模式匹配的热沉结构优化途径以及获得高效界面冷却效果的最佳脉冲驱动模式和控制策略。研究计划以实验为主导、数值模拟为支撑，为促进我国高密度封装领域热控管理由经验设计过渡到仿真优化设计提供理论与方法支持。

随着大规模通信设备和和数据处理器的封装微型化及接触界面高热流密度发展趋势，以界面热量传递为主的热管理问题普遍存在。为了提高热控组件内部各部件、构件、高功率密度器件热量传递性能的可靠性，则必须对系统中关键元件和大功率元器件集中的子系统进行温度控制。本项目首次提出3个表征热电过冷强化阶段的动态时间特征参数，量化分析了不同脉冲驱动模式作用于瞬态热电制冷效应的能量转换效率，揭示了主要热电效应的作用规律及能量分配机制，归纳得到与目标热源强度匹配的最优脉冲驱动参数和过程控制方案。研究结论得到从输入电功的高效转化目标出发，具有单调递增趋势的脉冲电压相比单调递减趋势的脉冲电压，更能保证实现更高效的热-电转化过程。而进一步权衡脉冲波形的经济性优势，以正弦波形最值得推荐，甚至超过了常用的方波形脉冲电压驱动实现的过冷强化作用效果。为了弥补冷侧热源削弱冷端界面制冷能力的不利影响，可以采取适当延长脉冲驱动时间或者增大脉冲突变幅度，以提供热源更多的额外帕尔贴制冷量。以上分析为脉冲模式驱动热电制冷器的运行过程控制、系统及其结构的优化设计和匹配，提供较为准确的理论预测和方案比较。