电容特性冲击能量收集效率

　　电容特性冲击能量收集效率

　　对于能量收集，电容器的选择需要仔细考虑的特性超过简单的电容值。在这些特性中，泄漏电流仍然是一个主要问题。今天，然而，设计师可以选择从低漏电电解电容器高性能的超级电容器生产商包括AVX、Kemet、麦斯威尔、村田、NESSCAP、精工、台哟宇扥、联合化工，等等。

　　电容器经常出现在许多设计情况下的事后考虑，添加到电路清理信号和电源。在信号采集，电容器发挥了核心作用，在过滤带源和采样和保持阶段的模拟/数字转换器。然而，在能量收集应用中，电容器提供了一个重要组成部分，从低能量的环境源积累电荷和放电存储电荷迅速和有效地加载到。在这些应用中，电容特性和元件选择上升作为设计的重要因素。

　　In their traditional roles in circuit design， capacitors are considered as constant capacitance components for filtering， decoupling， and any of the other familiar uses for these devices. For those purposes， differences between the characteristics of an ideal capacitor and those of a real capacitor typically do not greatly impact their ability to fill their role adequately. For energy-harvesting applications， however， the departure from an ideal capacitor significantly impacts the efficiency of the design as a whole.

　　Among common effects （Figure 1）， equivalent-series resistance （ESR） and leakage current dominate an array of non-ideal characteristics that can degrade efficiency. High ESR causes a capacitor to dissipate power， particularly when subject to high AC currents. As such， the use of low-ESR capacitors results in overall higher efficiency in an energy-harvesting subsystem. Leakage current exerts a more profound effect in designs using very-low-energy ambient sources — and rises as a significant limitation in the ability to apply more familiar types of capacitors in energy-harvesting designs.