Harmonic Power Standard at NIM and Its Compensation Algorithm

A new harmonic power standard has been developed at the National Institute of Metrology (NIM), Beijing, China, for the calibration of harmonic power analyzers under nonsinusoidal conditions at fundamental frequencies of 50 and 60 Hz. The standard is based on digital sampling techniques that do not require synchronization. A compensation algorithm is presented in this paper. A new definition of the uncertainty for harmonic measurement is proposed that is referred to the fundamental. A characterization signal and its application are introduced. Results have shown that over its operating range of up to 50 A, 500 V, and the sixtieth-order harmonic, the harmonic power standard has uncertainties $(k =2)$ of less than 30 $muhbox{V/V}$, 36 $mu hbox{A/A}$, and 42 $muhbox{W/VA}$ for voltage, current, and power measurements, respectively.