摘要
针对三相电网电压出现频率偏移时,传统锁相环响应速度慢、锁相精度差等缺点,提出一种基于坐标变换理论的新型数字锁相环,并建立了基于数字锁相环的三相电压型SVPWM整流器模型。首先对PWM整流器的基本拓扑进行分析,推导了其数学模型;分析了所提锁相环的电路结构和工作原理,并利用Matlab/Simulink对所建模型进行仿真。仿真结果表明:新型数字锁相环能够快速跟踪系统频率的变化,实现锁相功能;三相电压型PWM整流系统可实现单位功率因数运行;在三相电网电压频率出现小范围漂移情况下,新型锁相环也能够准确锁相。
A digital PLL（Phase Locked Loop） based on reference frame transformation theory is proposed to improve its response and accuracy under frequency jitter of three-phase voltage.The model of three-phase voltage-source SVPWM rectifier based on digital PLL is built.The circuit topology of PWM rectifier is analyzed and its mathematical model is derived.The circuit and principle of PLL are analyzed and the derived model is simulated with Matlab/Simulink.Results show that,the proposed PLL follows quickly system frequency change and the three-phase voltage PWM rectifier based on it realizes the operation of unity-power factor.
出处
《电力自动化设备》
EI
CSCD
北大核心
2011年第7期48-51,共4页
Electric Power Automation Equipment
基金
国家重点实验室自主课题资助项目(2007DA1051270-9304)~~
关键词
SVPWM
整流器
锁相环
功率因数
频率漂移
SVPWM
electric rectifiers
phase locked loops
electric power factor
frequency jitter
