摘要
提出了一种基于离散傅里叶变换(DFT)的改进软件锁相方法,克服了基于正弦信号相乘的瞬时鉴相方法信噪比极低及基于过零点检测的周期鉴相方法对过零点波形依赖性高的缺点。该方法采用调频和锁相两个过程共同作用实现锁相环(PLL)功能,在电网波形严重畸变、频率和电压闪变等异常状态时,能快速锁定目标信号基波分量的相位,实现较高的基波功率因数。通过5 kW样机的实验验证了该锁相方法具有很高的可行性。
An improved phase-locked method based on the discrete Fourier transform（DFT） is presented to overcome the low sigual-to-noise disadvantage of the instantaneous phase distinguishing method and the high dependence on the voltage waveform quality in the traditional zero-crossing detection phase-locked loop （PLL） method.The presented method combines the frequency modulation with the phase-locked together to realize prompt response on the funda- mental component of the voltage signal, moreover, the high power factor valve of the fundamental component can be achieved even the target signal is distorted and the frequency and voltage exist abnormal states.The feasibility of the improved method is verified on a 5 kW engineering prototype in the lab.
出处
《电力电子技术》
CSCD
北大核心
2012年第10期48-50,共3页
Power Electronics
基金
国家"863"项目(2011AA05A305)~~
关键词
逆变器
锁相环
功率因数
inverter
phase-locked loop
power factor
