Methodological Development and Design of Electrocaloric Cooling Systems for Electric Vehicle Applications

使用蒸汽压缩的常见制冷和空调技术与温室气体和高能源消耗有关。基于铁电效应的固体制冷因其绝热温变大、效率高等优点，近年来引起了人们的广泛关注。到目前为止，研究主要集中在材料的开发，特别是对电热材料的温度变化、工作温度和电场强度等性能的优化。实际应用几乎看不见。现有的解决方案大多是针对低传热率(例如芯片冷却)而设计的概念。缺少将电热材料集成到冷却应用中的方法。该项目的主要目标是以应用为导向开发电热冷却设备的通用概念和设置。在概念开发的范围内，将详细阐述设计电热冷却解决方案的新准则和方法。电迁移率是满足电热材料要求的一个完美的例子。需要散散少量的热量，并且可以提供高达400V的高压。我们将以锂离子电池冷却为例，开发基于直线运动和旋转运动以及静止设计的热传递概念。热有限元模拟将用于标注和优化EC概念。然后将建立优化的概念，并对冷却功率和效率进行表征。此外，还将开发控制概念，以提高效率。除了冷却效率的表征外，还将进行机械和功能疲劳分析。将通过将开发的概念与现有的传统和其他固态冷却解决方案进行比较来评估其应用潜力。

Common refrigeration and air-conditioning techniques using vapor compression are associated with greenhouse gases and high energy consumption. Solid state refrigeration based on ferroelectric effect has attracted considerable attention in recent years because of its high adiabatic temperature change and good efficiency. Up to now the research was mainly focused on material development, especially the optimization of the electrocaloric material properties like temperature change, operation temperature and electric field strength. Practical applications are hardly visible. Existing solutions are mostly concepts designed for low heat transfer rates (e.g. chip cooling). Methodical approaches of the electrocaloric material integration into cooling applications are missing. The main objective of this project is the application-oriented development of generic concepts and set-ups for electrocaloric cooling devices. Within the scope of concept development new guidelines and methods to design electrocaloric cooling solutions will be elaborated. Electromobility is a perfect example that meets the requirements of electrocaloric materials. Small amounts of heat need to be dissipated and high voltages up to 400 V are available. Heat transfer concepts based on linear and rotational movement as well as stationary designs will be developed using the example of Li-ion battery cooling. Thermal FEA-simulations will be used to dimension and optimize the EC-concepts. The optimized concepts will then be set-up and characterized concerning cooling power and efficiency. Further on control concepts will be developed to increase the efficiency. In addition to the characterization of the cooling efficiency a mechanical and functional fatigue analysis will be done. The application potential will be evaluated by comparing the developed concepts with existing conventional and other solid state cooling solutions.