| 摘要 |
<p>A digital power meter achieves enhanced accuracies through the utilization of a sequence of meter stage improvements. Such improvements include the utilization of a digital phase shift based cycle phase realignment following the scaling function of the meter. The cycle phase corrected signals are digitized utilising a sampling procedure wherein two samples of both current and voltage are taken within a precisely defined sampling interval. These samples are improved by the application thereto of a truncation correction and are averaged prior to being combined to provide quantity signals such as watt, VAR, volt, amperes, and the like. By developing subinterval transfer of components of these quantities to an overflow register, errors otherwise occurring at this stage of metering are substantially eliminated. <IMAGE></p> |
