电工技术学报2024，Vol.39Issue(14)：4432-4444,13.DOI:10.19595/j.cnki.1000-6753.tces.230814
单相级联整流器开路故障诊断和容错均压空间矢量脉宽调制算法
Open-Circuit Fault Diagnosis and Fault-Tolerant Voltage Balancing Space Vector Pulse Width Modulation Algorithm of Single-Phase Cascaded Rectifier
摘要
Abstract
The single-phase cascaded H-bridge rectifier(CHBR)used in the front of power electronic traction transformers has a highly modular structure,and its core component,power switching,has a high failure rate,dramatically impacting system reliability.To solve the open-circuit fault problem of its power switching device in the single-phase two-level H-bridge cascaded rectifier,this paper proposes a fast diagnosis algorithm based on an analytic model and a fault-tolerant voltage balancing space vector pulse width modulation(SVPWM)algorithm. Firstly,the topological structure and basic working mode of the single-phase two-level H-bridge rectifier are analyzed,and the mathematical model of the single-phase cascade rectifier is established.By analyzing the operation mode of each power switching device in a single module when the open-circuit fault occurs,a mathematical model of the current error rate of the cascaded rectifier is established.Accordingly,the characteristics of the current error rate of the single-phase two-level H-bridge cascaded rectifier with single or double open-circuit faults are analyzed accurately.Then,the specific flow of the diagnosis algorithm is provided. Secondly,based on the one-dimensional SVPWM algorithm,the one-dimensional space vector graph is established,and the influence of switch fault on vector selection is analyzed.Then,the redundant vector and redundant switch state of the cascaded converter are used to reselect the fault-tolerant vector to avoid the action of the faulty switch tube and restore the rectifier to normal operation.The selected vector still has the voltage-sharing function.The selection strategy of voltage equalization and fault tolerant voltage equalization vector is proposed for two and n-module cascade rectifiers with open-circuit faults,and the implementation steps of fault-tolerant voltage equalization SVPWM algorithm are given. Finally,the open-circuit fault diagnosis algorithm and the fault-tolerant voltage equalization SVPWM algorithm for six-module single-phase cascade rectifiers are verified by Matlab/Simulink simulation.Moreover,through the FPGA-based two-module cascade rectifier hardware experiment platform and the Verilog-based software platform,fault diagnosis and fault tolerant experiments under single or double open-circuit faults are conducted.The following conclusions are obtained:(1)The open-circuit fault diagnosis algorithm can localize single or double tubes within 1/4 of a fundamental wave cycle,and the speed is fast.Moreover,this algorithm requires minimal computation without additional hardware.It has the advantages of simplicity,speed,and high feasibility,suitable for multi-module cascaded converter systems.(2)The fault-tolerant voltage balancing SVPWM algorithm can achieve fault tolerance for single or double tube open-circuit faults without additional circuits.In addition,it can restore the rectifier to normal operation under single-tube open-circuit faults and double-tube open-circuit faults of types Ⅰ and Ⅱ,respectively.The system can also maintain the DC voltage balance of each module under unbalanced loads after fault tolerance.关键词
单相级联H桥整流器/开路故障/在线诊断/空间电压矢量调制/容错算法Key words
Single-phase cascaded H-bridge rectifier/open-circuit fault/online diagnosis/space voltage vector modulation/fault tolerant algorithm分类
信息技术与安全科学引用本文复制引用
徐翊宸,杨双寿,王悦,杨帆,马兰,舒泽亮..单相级联整流器开路故障诊断和容错均压空间矢量脉宽调制算法[J].电工技术学报,2024,39(14):4432-4444,13.基金项目
国家重点研发计划(2021YFB2601500)和国家自然科学基金(52077183)资助项目. （2021YFB2601500）
