| 摘要 |
PURPOSE:To form a dead time of signal easily and surely at the secondary side of a current transformer, by providing a power supply and switching circuit to flow rectangular pulse currents being opposite with each other, and a switch circuit, and establishing tri-state of positive, negative and zero, at the secondary side with switch operation. CONSTITUTION:A primary conductor P1 of a current transformer CT is connected to a DC power supply E1 via a switch S1 and other primary conductor P2 is connected to a DC power supply E2 via a switch S2 respectively, and the polarity is selected so that opposing current flows to the conductors P1 and P2. When the switch S1 is closed, a current I1 flows to the conductor P1 and when the switch S2 is closed, a rectangular pulse current I2 opposite to the current I1 and equal in the amplitude flows to the conductor P2. When the switches S1, S2 are closed so that the currents I1, I2 flow at the same time, the magnetic flux by both the currents is canceled into zero, and the secondary output of the current transformer goes to zero. When the switches are actuated so that a part of the currents I1, I2 is overlapped at the front and rear edge of the pulse, the secondary output of the current transformer shows positive and negative polarities having a dead time. |
