为探究介电弹性体发电机发电量与其拉伸变形的关系,采用单轴、纯剪切与双轴3种拉伸模式进行介电弹性体发电机发电性能的实验研究.分析了介电弹性体发电机在3种拉伸模式下电压、电容、电极涂覆面积与拉伸率的关系,实验研究了3种拉伸模式下介电弹性体发电机输出电压、实际产生电能、拉力与其变形量的关系及介电弹性体的破裂极限.实验和研究结果表明,双轴拉伸模式下介电弹性体的破裂极限最大,在面积变换率大于4倍时电能出现大幅度提升,可实现介电弹性体的能量密度最大化.

为研究介电弹性体发电机的发电特性,基于COMSOL有限元软件建立了在纯剪切拉伸方式下的介电弹性体发电机有限元仿真机电耦合模型.该模型基于Y eo h超弹性材料本构,同时耦合发电机膜内静电力,根据可变电容理论对发电机电容变化及发电效果进行研究.设计了可Y向预拉伸的纯剪切拉伸装置,并在不同预拉伸条件下对发电机薄膜样本进行了拉伸实验,分析了其电容变化及发电效果.对比了仿真数据与实验结果,仿真模型的电容变化与实验测得的电容变化情况基本吻合,仿真模型一个周期内的输出电压变化与实验测得的电压变化基本吻合.实验及仿真结果表明,在相同的拉伸条件下,Y向预拉伸增大了初始电容及电容变化速率,且当Y向预拉伸λ=1时的上升电压为83 V,而λ=2时的上升电压达到252 V,改善了发电性能.本文提出的介电弹性体发电机新的研究方法为发电机样机设计提供了新的思路.

In order to improve the conversion efficiency of micro energy harvesting,three typical generators were studied and their equivalent circuits were analyzed.The working principles,advantages and disadvantages and energy conversion efficiency of three energy harvesting devices were discussed.Typical energy storage devices were compared.The results showed that the energy harvesting circuit with control unit was the most effective one,supercapacitor and lithium battery were suitable for micro energy harvesting system.Based on the analyses,some advises were proposed for the micro energy harvesting technology and energy storage devices.Combining the energy harvesting circuits with control unit and combined form of energy storage system would be one of the directions for further research on the efficiency of micro energy harvesting system.

针对目前波浪能发电成本高、结构复杂、能量转换效率低等问题,对波浪能发电的基本原理、新型发电装置及相关新技术进行了研究.具体对直线电磁型、压电型和电活性聚合物型波浪能发电装置进行了总结和分析,探究了点吸式、振荡水柱式、振荡摇摆式和筏式等波浪能捕获装置的工作原理、优缺点、适用场合和应用前景,特别对新型的波浪能发电技术—介电弹性体发电机进行了分析和探究;同时对波浪能发电技术的进一步发展提出了建议.研究结果表明,对比其他方式的波浪能捕获装置,基于介电弹性体的波浪能装置发电成本更低,结构更加简单,能量转换效率更高.