| 摘要 |
PURPOSE:To improve the driving efficiency of capacitive load by performing the switching at the time of withdrawing, preserving, and transferring the electrostatic energy with the capacitive element and the inductor connected in parallel with a power source and capacitive load, with the gate of a field effect transistor being electrically insulated. CONSTITUTION:Capacitive load 80 is connected to a DC power source 20 through switches 30, 50, and 70. A control circuit 90 performs the switching of switches 30, 50, and 70, based on power source voltage V1, load current I, and load voltage V3. The electrostatic energy is withdrawn and preserved in a capacitive element 40 from the power source 20, and next is transferred to an inductor 60, and further is transferred to the capacitive load 80. The switching of the switches 30-70 is performed repeatedly by the electrically insulated gate of a field effect transistor. The series resonance frequencies between the capacitive element 40 and the inductor 60 and between the inductor 60 and the capacitive load 80 are selected sufficiently larger than the driving frequency of a resonant switching power source 10. Hereby, the capacitive load can be driven efficiently. |
