基于电压注入的双PWM变流器直流母线电容的在线检测  

Online Detection of DC-link Capacitors for Dual-PWM Converter based on Voltage Injection

作　　者：高亚真 黄守道[1] 付雪婷 王海龙[1] 付睿潇 GAO Yazhen;HUANG Shoudao;FU Xueting;WANG Hailong;FU Ruixiao(Hunan University,Changsha 410082,China)

机构地区：[1]湖南大学,长沙410082

出　　处：《大电机技术》2018年第6期79-83,共5页Large Electric Machine and Hydraulic Turbine

基　　金：国家自然科学基金青年项目(51707062);中国博士后科学基金资助项目(2016M602407)

摘　　要：本文提出了一种三相双PWM变流器的直流母线电容的在线检测方法。在空载条件下,将一个频率略低于母线频率的交流电压信号注入到双PWM变流器的直流母线电压中,在直流输出侧产生同频率的功率波动。通过使用数字滤波器提取直流输出端的交流电压和功率分量,利用最小二乘法可以估算出直流母线电容。所提出的方法可以仅通过软件实现而无需额外的硬件,Matlab/Simulink仿真实验结果表明使用此方法得到的电容值估算误差较小。In this paper,a new method for the online estimation of DC-link Capacitors in three-phase AC-DC-DC PWM converter was proposed.At no-load condition,a controlled AC voltage with a lower frequency than the line frequency is injected into the DC-link voltage,which then causes the AC power ripples at the DC output side.By extracting the AC voltage and power components on the DC output side using digital filters,the capacitance can be calculated by using the recursive least squares(RLS)method.The proposed method can be implemented by software alone without additional hardware.The simulation results of Matlab/Simulink show that the error of capacitance value obtained by this method is very small.

关 键 词：双PWM变流器 电容估算 电压注入 数字滤波器 最小二乘法(RLS) 

分 类 号：TM46[电气工程—电器]