PURPOSE: To suppress reverse of a signal current to an inverter circuit by providing a tertiary winding in a transformer which couples the inverter output to a high voltage distribution line and coupling the signal current output of the inverter circuit to a primary winding through the tertiary winding.
CONSTITUTION: A primary winding N1 of a transformer 2 is connected to a high voltage power source having a commercial frequency, and low voltage windings N2 and N3 are connected to the secondary side, and numbers n1∼n3 of turns of windings N1∼N3 are set to satisfy n1>n3>n2. An inverter 3 is connected to the winding N2 to generate a high frequency signal current, and it is connected to the winding N3 through a coupling circuit 4 which has a high impedance for the commercial frequency and has a low impedance for the signal current. A signal current IS outputted from the coupling circuit 4 and a signal voltage Vout generated by the impedance of the winding N3 induce a lower signal voltage Vin in the winding N2. Thus, sneaking of the output of the inverter 3 is reduced to transmit efficiently an answer back signal to the winding N1.
| JP6500899 | Insulated DC power supply device |
| WO/1999/044397 | LIGHTS |
| WO/1991/008606 | AUTOMATIC HOUSE-CIRCUIT CONTROL SYSTEM |
WATANABE SUSUMU
KAMIMURA RIYOUICHI
