| 摘要 |
<p>Current flow at a line frequency may be measured from a source using matched voltage drops in a pair of voltage drop circuits. The voltage drop circuits may each includes a fixed value component, such as a resistor, and an adjustable value component, such as an adjustable current source, coupled in series. The adjustable valued components may be controlled based on differences in voltage drops produced by the voltage drop circuits based on a high-frequency signal, higher in frequency than the line frequency, applied to a control input for each of the adjustable value components.</p> |
