| 摘要 |
<p>PURPOSE:To enable three-phase voltage detection by one voltage detecting amplifier by superposing a voltage, obtained by inverting the phase of a voltage induced at a voltage detection electrode nearby a conductor of one phase, upon voltages induced at electrodes nearby conductors of other two phases. CONSTITUTION:This device detect the voltage of the high-voltage equipment where a three-phase current flows. Here, the voltage detection electrodes 4 - 6 are provided nearby the conductors 1 - 3 of the respective phases of the high-voltage equipment. Then an inverting amplifier 7 is connected to the electrode 4 arranged nearby the conductor 1 of one specific phase, its induced voltage is inverted in phase and superposed upon the voltages induced at the electrodes 5 and 6 arranged nearby the conductors 2 and 3 of other two phases, and the resulting voltage is inputted to the voltage detecting amplifier 8. Here, a rectified voltage is compared with a specific st voltage to decide whether or not there is the voltage of the high-voltage equipment.</p> |
