电力系统保护与控制
電力繫統保護與控製
전력계통보호여공제
POWER SYSTM PROTECTION AND CONTROL
2014年
21期
29-33
,共5页
电力系统%频率测量%周期过零点%谐波%DFT%FIR(数字滤波器)
電力繫統%頻率測量%週期過零點%諧波%DFT%FIR(數字濾波器)
전력계통%빈솔측량%주기과영점%해파%DFT%FIR(수자려파기)
power system%frequency measurement%periodic zero-crossing point%harmonic%DFT%finite impulse response (FIR)
为解决非同步定频采样系统对电力系统频率测量时存在的运算复杂、实时性不好等问题，提出了一种实用的频率实时测量方法。该方法是基于周期过零点插值原理，通过对A/D采样的离散序列进行FIR带通数字滤波，然后对相邻的同方向过零点进行插值求取频率的估计值。针对电力系统待测信号中不含谐波、含有2-16次谐波以及含有随机噪声的不同情况，分别进行了仿真验证，最后与离散傅里叶变换（DFT）测频算法的结果进行了对比。结果表明该方法抗干扰性和测量精度都要优于DFT测频算法，而且该方法计算量少、实用性强、实时性好、测量精度高，能满足电力系统频率测量要求。
為解決非同步定頻採樣繫統對電力繫統頻率測量時存在的運算複雜、實時性不好等問題，提齣瞭一種實用的頻率實時測量方法。該方法是基于週期過零點插值原理，通過對A/D採樣的離散序列進行FIR帶通數字濾波，然後對相鄰的同方嚮過零點進行插值求取頻率的估計值。針對電力繫統待測信號中不含諧波、含有2-16次諧波以及含有隨機譟聲的不同情況，分彆進行瞭倣真驗證，最後與離散傅裏葉變換（DFT）測頻算法的結果進行瞭對比。結果錶明該方法抗榦擾性和測量精度都要優于DFT測頻算法，而且該方法計算量少、實用性彊、實時性好、測量精度高，能滿足電力繫統頻率測量要求。
위해결비동보정빈채양계통대전력계통빈솔측량시존재적운산복잡、실시성불호등문제，제출료일충실용적빈솔실시측량방법。해방법시기우주기과영점삽치원리，통과대A/D채양적리산서렬진행FIR대통수자려파，연후대상린적동방향과영점진행삽치구취빈솔적고계치。침대전력계통대측신호중불함해파、함유2-16차해파이급함유수궤조성적불동정황，분별진행료방진험증，최후여리산부리협변환（DFT）측빈산법적결과진행료대비。결과표명해방법항간우성화측량정도도요우우DFT측빈산법，이차해방법계산량소、실용성강、실시성호、측량정도고，능만족전력계통빈솔측량요구。
To solve the problem of asynchronous frequency-fixed and sampling system’s complex computation and weak real-time for power system frequency measurement, a practical real-time frequency measurement algorithm is proposed. This method is based on the interpolation principle of periodic zero-crossing point, the frequency estimated value is calculated by digital filtering of FIR band-pass for A/D sampling discrete sequence and by interpolating for adjacent zero-crossing point with the same direction. The signal under test in power system is simulated and vertified under three different circumstances: excluding harmonic, including second to sixteenth harmonic and the random noise. The simulation result is compared with that of Discrete Fourier Transform (DFT) method. The result shows that this method is superior to DFT in anti-interference and measurement accuracy, it can satisfy the requirement of frequency measurement for power system due to its simplicity, strong practicability, high instantaneity and measurement accuracy.
