Power calibrator using sampled feedback for current and voltage

A power calibration source for periodic signals is described that consists of digitally synthesized voltage and current channels, the outputs of which are controlled by synchronous sampled feedback. This system results in accurate voltage- and current-waveform conformity and stability in amplitude and phase at high power levels, regardless of power-factor or frequency setting. The system compensates for errors in calibration normally caused by amplifier nonlinearity and loading.