中山大学学报(自然科学版)
中山大學學報(自然科學版)
중산대학학보(자연과학판)
ACTA SCIENTIARUM NATURALIUM UNIVERSITATIS SUNYATSENI
2014年
4期
40-44
,共5页
FFT%小波变换%电能质量
FFT%小波變換%電能質量
FFT%소파변환%전능질량
FFT%wavelet transform%power quality
该文研究应用FFT在频域与小波变换在时域的优势,设计搭建了基_4 FFT与Daub4小波变换结合的嵌入式电能质量检测系统。该系统利用小波变换检测电压骤升、骤降等暂态问题,使用FFT分析稳态下电信号谐波。为验证系统的实际检测能力,分别对稳态、电压骤降、电压暂态干扰三种状况进行了实时监测测试和Matlab软件分析,结果表明:该嵌入式电能质量检测系统在稳态时,检测基波幅值的误差为0.3%,满足公用电网GB/T 14549-93对谐波测量仪器的A级标准;同时,在电压骤降、电压暂态干扰状态下也能准确检测到电信号的突变时间,实际系统检测和软件仿真结果误差在1.6 ms内,满足实时性要求。
該文研究應用FFT在頻域與小波變換在時域的優勢,設計搭建瞭基_4 FFT與Daub4小波變換結閤的嵌入式電能質量檢測繫統。該繫統利用小波變換檢測電壓驟升、驟降等暫態問題,使用FFT分析穩態下電信號諧波。為驗證繫統的實際檢測能力,分彆對穩態、電壓驟降、電壓暫態榦擾三種狀況進行瞭實時鑑測測試和Matlab軟件分析,結果錶明:該嵌入式電能質量檢測繫統在穩態時,檢測基波幅值的誤差為0.3%,滿足公用電網GB/T 14549-93對諧波測量儀器的A級標準;同時,在電壓驟降、電壓暫態榦擾狀態下也能準確檢測到電信號的突變時間,實際繫統檢測和軟件倣真結果誤差在1.6 ms內,滿足實時性要求。
해문연구응용FFT재빈역여소파변환재시역적우세,설계탑건료기_4 FFT여Daub4소파변환결합적감입식전능질량검측계통。해계통이용소파변환검측전압취승、취강등잠태문제,사용FFT분석은태하전신호해파。위험증계통적실제검측능력,분별대은태、전압취강、전압잠태간우삼충상황진행료실시감측측시화Matlab연건분석,결과표명:해감입식전능질량검측계통재은태시,검측기파폭치적오차위0.3%,만족공용전망GB/T 14549-93대해파측량의기적A급표준;동시,재전압취강、전압잠태간우상태하야능준학검측도전신호적돌변시간,실제계통검측화연건방진결과오차재1.6 ms내,만족실시성요구。
The advantages of FFT application in frequency domain and wavelet theory in time domain were studied , and an Embedded System for Power Quality Detection ( ESPQD ) based on radix-4 FFT and Wavelet Transform is developed .The ESPQD uses the wavelet theory to monitor the transient power qualityincluding voltage dip , voltage swell and so on .FFT is applied to analysis harmonics of electrical signals in steady-state.Three different states including steady-state, voltage dip and transient interference were tested with both the ESPQD hardware system and Matlab simulation for verification .The results show that the amplitude error of fundamental wave is within 0.3%, meeting the A level standard of the u-tility grid standards GB/T 14549-93 about harmonic measuring instruments .The system can also pre-cisely and quickly detect the abrupt changes of the electrical signals during voltage dip and transient in -terference .The time difference between ESPQD and simulation is within 1.6 ms and the system can be used in real time measurement .