电工技术学报2024，Vol.39Issue(20)：6282-6292,11.DOI:10.19595/j.cnki.1000-6753.tces.231507
基于多级电容电场感应取能周期性供电电源的优化设计方法
Optimization Design Method for Periodic Power Supply Based on Multi-Stage Capacitor Electric Field Energy Harvesting
摘要
Abstract
With the development of the smart grid,a large number of new sensors have entered the power system,taking an essential part in the online monitoring system of the power grid.On the sensor power supply source,the drawbacks of the traditional power supply mode can be effectively solved by utilizing environmental energy to supply online monitoring devices.Electric field energy has a stable energy supply,which can be used as a reliable power source for online monitoring devices of power transmission and transformation equipment.However,in practical applications,due to the low power consumption of electric field-induction energy harvesting methods,the intermittent time of online monitoring devices is long.This paper proposed a structure and control method for the electric-field energy harvesting power source based on the multi-stage capacitor to reduce device losses and volume and improve energy transfer efficiency. Firstly,the disconnector is selected as a practical application scenario.By constructing an equal-scale finite element model,the influence of the area and installation position of the energy harvesting electrode on the energy harvesting performance is obtained.Secondly,the structure of the electric field energy harvesting circuit for multi-stage capacitors and its working logic are introduced.This circuit operates in a periodic mode.When using two-stage energy harvesting capacitors,each working cycle can be divided into three stages:the charging stage,the first-stage capacitor discharge stage,and the second-stage capacitor discharge stage.When the second stage energy harvesting capacitor is discharged,it enters the next work cycle.Thirdly,by simplifying the equivalent circuit of the discharge circuit of the energy harvesting capacitor and solving the state equation of the circuit in parallel,the energy transfer efficiency expression for each stage of energy harvesting capacitor discharge is obtained.Finally,the capacitance values of the energy harvesting capacitor and energy storage capacitor are selected based on the actual energy demand of the sensor load.The influence of transformer turn ratios on the energy achievable per cycle and energy transfer efficiency is analyzed.Then,the optimal transformer turn ratio is selected to optimize the energy harvesting performance. The results show that when the energy harvesting capacitors reach the discharge threshold voltage,the first-stage energy harvesting capacitor begins to discharge.After discharge,the second-stage energy harvesting capacitor continues to discharge.After both energy-harvesting capacitors are discharged,the circuit enters the next working cycle.When the capacitance values of the energy collection and the energy storage capacitors are selected as 1.675 μF and 1 000 μF,and the discharge threshold voltage of the energy collection capacitor is set to 500 V,the energy collection performance of multi-winding transformers with different turn ratios is compared.When the turn ratio of the transformer is selected as 1 500/1 500/88,the energy transfer efficiency of the discharged energy harvesting capacitor is the highest,reaching 54.4% .This circuit can obtain 226 mJ of energy per cycle,which meets the wireless current sensor operation requirements for 1.648 seconds and sends 3 online monitoring data.关键词
在线监测/电场取能/隔离开关/充放电控制/无线电流传感器Key words
Online monitoring/electric field energy harvesting/disconnector/charging and discharging control/wireless current sensor分类
信息技术与安全科学引用本文复制引用
王维,任翰林,许晨进,段名荣..基于多级电容电场感应取能周期性供电电源的优化设计方法[J].电工技术学报,2024,39(20):6282-6292,11.基金项目
国家自然科学青年基金项目(51807095)、江苏省333高层次人才培养工程专项(3-16-292)和江苏省高等学校基础科学(自然科学)研究项目(22KJB470021)资助. （51807095）
