INVERTER DEVICE, PLASMA GENERATOR APPARATUS AND CONTROL METHOD

摘要

An inverter device includes a switching device which performs on-off switching of an input voltage, a step-up transformer which applies an excitation current to its winding during a switching-device-on period and outputs an output voltage during a switching-device-off period, an input-voltage detector which detects the input voltage and output an input-voltage detection signal, an output voltage detector which detects the output voltage and output an output-voltage detection signal, an output-produced-period detector which detects a period when the output voltage is produced based on the output-voltage detection signal, a comparator which detects a period when the output-voltage detection signal exceeds the input-voltage detection signal and output information indicating the output-high period, and a shifting unit which shifts the information indicating the output-high period to a next period when absence of the output produced period is detected. The control unit adjusts the switching-device-on period based on information indicating the shifted output-high period.

主权项

1. An inverter device comprising:
a switching device configured to perform on-off switching of an input voltage in accordance with on-off control provided by a control circuit; a step-up transformer including an excitation winding and an output winding and configured to apply an excitation current to the excitation winding during a period in which the switching device is on but output an output voltage exhibiting a half-wave alternating-current waveform from the output winding during a period in which the switching device is off; an input-voltage detector configured to detect a state of the input voltage by detecting a voltage value of the input voltage; an output voltage detector configured to detect a state of the output voltage by detecting an instantaneous voltage value of the output voltage; an output-produced-period detector configured to detect an output produced period during which the output voltage is produced based on the output-voltage detection signal output from the output-voltage detector; a comparator configured to detect an output-high period during which the output-voltage detection signal exceeds the input-voltage detection signal by making comparison between the input-voltage detection signal output from the input-voltage detector and the output-voltage detection signal output from the output-voltage detector; and a shifting unit configured to shift the information indicating the output-high period detected by the comparator to a next period in which the output-produced-period detector detects absence of the output produced period, wherein the control circuit is configured to adjust the period in which the switching device is to be switched on based on information indicating a shifted output-high period, the shifted output-high period being the output-high period shifted by the shifting unit.