摘要
有源电力滤波器(APF)在谐波治理方面有着广泛应用,其谐波补偿性能在很大程度上取决于谐波检测环节的性能。为了提升谐波检测速度,该文提出一种基于滑窗离散傅里叶变换(SDFT)的快速谐波检测算法。相较于传统滑窗离散傅里叶算法存在一个基波周期延时,该文提出的快速谐波检测算法利用三相系统的对称性,替换传统滑窗离散傅里叶变换谐波检测算法的梳状滤波器构成环节,能在1/6个基波周期内实现谐波的有效检测,降低检测延迟。该文首先分析传统滑窗离散傅里叶变换谐波检测算法的优缺点;其次推导所提出的快速谐波检测算法的Z域表达式并分析其特点;最后通过仿真及小功率缩比有源电力滤波器样机实验平台验证了所提出的快速谐波检测算法的有效性。
The active power filter(APF)can compensate harmonics caused by nonlinear equipment such as high-frequency power electronic devices.Whether its harmonic detection algorithm can detect the harmonic component quickly and accurately largely determines the dynamic response and harmonic compensation performance of APF.The traditional discrete Fourier transform(DFT)was a frequency domain harmonic detection method,which can detect specific harmonics.However,it had large computation and long delay and,hence,can not detect harmonics quickly and compensate them in time.This was insufficient to support fast harmonic compensation of APF.Recently,some methods introduced the sliding window iterative algorithm into DFT,but there was still delay of a fundamental period.To address these issues,this paper proposes a new sliding-window discrete Fourier transform(SDFT)algorithm for three-phase symmetric systems.By using the symmetry of three-phase signals,it effectively detects harmonics within 1/6 fundamental cycle.This method is based on DFT and sliding window iterative algorithm.Firstly,the DFT algorithm needs N complex multiplications to detect a specific order harmonic.The sliding window iterative algorithm updates the datas using cyclic sliding pointer,reducing the calculation to one complex multiplication,thus leading to the delay of one fundamental period.Secondly,the z-domain transfer function of DFT is composed of a comb filter,a complex resonator and gain coefficient.The method proposed in this paper uses a new comb filter,which makes use of the characteristic that the sampling value of B and C phase signals in three-phase symmetric signals can replace the partial sampling value of phase A as the input sequence of DFT calculation.It only needs 1/6 fundamental period to obtain the output sequence of the harmonic components.This way,the problem that SDFT requires one fundamental cycle delay is addressed,and APF can detect and compensate harmonics more quickly.The test results in the simulation model with the fundamental freq
作者
叶宗彬
侯波
张延澳
秦嘉盛
张旭隆
Ye Zongbin;Hou Bo;Zhang Yan’ao;Qin Jiasheng;Zhang Xulong(School of Electrical Engineering China University of Mining and Technology,Xuzhou 221116 China;School of Electrical and Control Engineering Xuzhou University of Technology,Xuzhou 221018 China)
出处
《电工技术学报》
EI
CSCD
北大核心
2023年第2期510-522,共13页
Transactions of China Electrotechnical Society
基金
中央高校基本科研业务费专项资金资助项目(2019XKQYMS36)。
关键词
离散傅里叶变换
特定次谐波检测
有源电力滤波器
滑窗迭代
Discrete fourier transform
selective harmonic detection
active power filter
sliding-window iterative
