| 摘要 |
<p>An apparatus for measuring electrical power is described wherein the apparatus is adapted to produce an output signal proportional to the product of a supply voltage and current flowing through a load connected thereto. A first signal proportional to the supply voltage and a second signal proportional to the load current are used to modulate the period of two constant frequency carrier signals. At least one of the modulated signals is averaged by signal processing means to provide a reference value for the apparatus. Multiplication of the modulated signals by the microprocessor produces the power product output signal. Successive values of the period-modulated voltage-related signal are accumulated. The accumulated value is periodically latched and fed to a computer. A pulse counter and timer may be provided to receive and measure the voltage-related period varying-signal.</p> |
