초록 ▼

In order to obtain a simple circuit structure for a measuring device with high measuring accuracy, it is provided that current and voltage signals of a load are fed to a multiplexer and, after digitization, are multiplied by one another. In order to compensate for external angle errors, different wa

In order to obtain a simple circuit structure for a measuring device with high measuring accuracy, it is provided that current and voltage signals of a load are fed to a multiplexer and, after digitization, are multiplied by one another. In order to compensate for external angle errors, different waiting cycles are generated between the current and voltage values in the digital signal. A measuring device and a method are provided for this purpose. A preferred application is in electricity meters.

대표청구항 ▼

[ I claim:] [1.]1. An electrical power measuring device, comprising:a multiplexer for receiving input signals including a current signal and a voltage signal to be measured;an analog-to-digital converter connected to and disposed downstream of said multiplexer, said analog-to-digital converter being

[ I claim:] [1.]1. An electrical power measuring device, comprising:a multiplexer for receiving input signals including a current signal and a voltage signal to be measured;an analog-to-digital converter connected to and disposed downstream of said multiplexer, said analog-to-digital converter being a sigma-delta modulator receiving the current signal and the voltage signal and outputting a digital serial signal formed of digitized values of the current signal and the voltage signal;a digital processor connected to and disposed downstream of said sigma-delta modulator and receiving the digital serial signal from said sigma-delta modulator;a decimation filter connected between said sigma-delta modulator and said digital processor; anda control logic unit connected to said decimation filter and generating predeterminable waiting cycles in each case between the digitized values of the current signal and the voltage signal forming the digital serial signal for forming respective power values, said control logic unit driving said decimation filter such that a predetermined phase angle is generated between the digitized values of the current signal and the voltage signal in the digital serial signal.