| 摘要 |
The device for supplying electrostatic force of the present invention comprises: an alternating-current power-source supply unit for supplying an alternating-current power source; a rectifying circuit which receives and rectifies the alternating-current power source from the alternating-current power-source supply unit; a drive coil which is connected in series to a load supplied with electrical power from the rectifying circuit; a freewheeling diode of which the two ends are respectively connected to the output side and the input side of the load so as to be connected in parallel to the load, and which is provided in the direction in which the current flows from the output side to the input side of the load and which makes the current accumulated in the drive coil discharge to the load when a power switch is turned off; a power switch for switching current which has passed through the drive coil and load; and a drive-signal-generating unit which is connected to a gate terminal of the power switch, determines the basic adjustment time of the drive-signal-generating unit by measuring the maximum value of the rectified voltage in units of one cycle of the rectified voltage, controls the power switch by using the 90° and 270° points of the input voltage phase as the basic adjustment time, generates a switch drive pulse wider than the basic adjustment time when the input voltage phase is at or above either the 0° or the 180° point, and controls the pulse width by interpolation for the rest of the intervening time. When the device for supplying electrostatic force of the present invention is employed, power of various magnitudes and frequencies can be supplied to the load in a stable fashion, even without providing a high-capacity capacitor for use in smoothing circuits which affects the life of power-source supply devices. |
