摘要 |
PURPOSE:To reduce the capacitance of the communication capacitor and to decrease the dielectric strength of the communication capacitor by providing a DC circuit comprising a capacitor and a diode in parallel with a series circuit section consisting of a communication reactor and the communication capacitor. CONSTITUTION:The communication capacitor 5 supplying a communication energy to interrupt a load current and a capacitor 12 absorbing the energy stored in an inductance at the interruption are provided, no communication energy is charged in the capacitor 12 and the capacitor 12 is used to absorb only the energy caused at the interruption. Since the communication capacitor 5 does not absorb the energy produced at the interruption, the charge voltage is not abnormally increased at the communication. Thus, the capacitance of the communication capacitor is reduced and the dielectric strength of the communication capacitor is decreased. |