| 摘要 |
PURPOSE:To reduce the switching loss of an oscillation transistor (Tr) at oscillation time by phase-operating a signal from the tertiary winding of a conversion transformer by a phase controller. CONSTITUTION:A capacitor 23 is charged by positive polarity as shown by + by the configuration of a series charging circuit of a parallel resistor of phase control resistors 18, 20, a coupling capacitor 23 and a thyristor 27 for an induced voltage generated in the shown polarity of a tertiary winding 37 for the base of an oscillation Tr32. On the contrary, the positive polarity as shown by + is charged in the configuration of a series discharging circuit of a resistor 20 and a capacitor 23 through a commutation diode 28 by the reverse polarity induced voltage shown of the tertiary winding 37. In other words, the capacitor 23 is charged in positive polarity by altering the charging/ discharging time constant through the capacitor 23. Thus, a base current junction is delayed to the time when the collector voltage of the Tr32 decreases to prevent the loss at the rising time of the switching operation of the Tr32. |
