A method of compensation of the frequency dependent systematic error of the time-division watt-converter

The paper presents a method for the compensation of the frequency dependent systematic error of the Time-Division Multiplier of the Goldberg type (TDM). The method Is based on using the additional correcting circuits on the TDM inputs whereby theoretically perfect compensation can be achieved under conditions derived analytically in this paper. Applying this method it is possible to compensate the systematic error in a relatively large range of input signal frequencies even in the cases when both input signals are not limited to one single frequency but have harmonics. In order to verify the performances of the method an adequate, high precision TDM based watt-converter has been developed. Theoretically and experimentally it is shown that the high performances (accuracy better than /spl plusmn/100/spl times/10/sup -6/) of the multiplier can be obtained in the input frequency range from 50 Hz to 20 kHz even in the case when the conversion frequency is only 10 times the input signal frequency.