| 摘要 |
<p>Arrangement to determine at least one electrical feature of an electrical device (1). The arrangement comprising a signal injection unit (8) configured to inject a first test signal (t<SUB>1</SUB>) at a first main frequency (f<SUB>1</SUB>) into a first electric circuit (10), and to inject a second test signal (t<SUB>2</SUB>) at a second main frequency (f<SUB>2</SUB>) into the first electric circuit (10) or into a second electric circuit (30), a signal conversion unit (7) configured to measure a first and a second electrical quantity in the first electrical circuit resulting from the first test signal (t<SUB>1</SUB>), and to measure the first and second electrical quantity in the first (10) or second electric circuit (30) resulting from the second test signal (t<SUB>2</SUB>),and a processing device (18) including at least two analogue input channels (16,17) configured to receive the measured electrical quantities and to determine the electrical feature based on the measured electrical quantities, a mixing unit (13) configured to add the measurements (U<SUB>1</SUB>,U<SUB>2</SUB>) of the first electrical quantity from the first and second testsignals and based thereon generate a first mixed signal, to add the measurements (I<SUB>1</SUB>,I<SUB>2</SUB>) of the second electrical quantity from the first and second test signals and based thereon generate a second mixed signal, to supply the first mixed signal to a firstinput channel of the processing device and to supply the second mixed signal to a second input channel of the processing device. The processing device is configured to decompose the mixed signals to obtain the measurements of the first and second electrical quantities.</p> |
