| 摘要 |
<p>PURPOSE:To make it possible to achieve excellent transmission of a voltage signal by obtaining an output voltage without the effects of the decrease in output in a low-frequency region and nonlinear distortion in a magnetic circuit. CONSTITUTION:For example, when the frequency of an AC input voltage to be converted Ei is about a reference frequency (50-60Hz) or higher than the reference frequency, a current negative feedback circuit is operated. A converted voltage Eo having the specified corresponding relationship with the input voltage Ei appears across both ends of a reference resistor Ro by an AC zero flux method without the effect of the nonlinearity of a magnetic circuit. When the frequency of the input voltage Ei is lower than, e.g. the reference frequency, the induced electromotive force generated in a detecting coil 4 is added into an amplifier 5 through a voltage input path. The converted current is added to the current flowing into the negative feedback circuit. Therefore, the residual magnetic flux in a magnetic core 1 is offset. The converted voltage Eo having the specified corresponding relationship is obtained in any case. Thus, the excellent transmission of the voltage signal can be performed.</p> |
