Patent ID: 9137885
Filing Date: 2015-09-15
Classification: H01J,H02M,H05H

Abstract:
1. A direct current power supply device, comprising a current source step-down type chopper forming a direct current source, a multiphase inverter for converting a DC output from the current source step-down type chopper into multiphase AC power by operating multiple switching elements, a rectifier for subjecting an output from the multiphase inverter to AC-DC conversion to supply direct current being obtained to a load, and a controller having a chopper controller for controlling the current source step-down type chopper and an inverter controller for controlling the multiphase inverter, the controller performing, switching control, being controlled by the chopper controller, for switching between an ignition mode for supplying ignition voltage which generates plasma discharge in a plasma generator and a steady operation mode for maintaining the plasma discharge in the plasma generator, and intermittent short-circuit control for establishing a short-circuit intermittently, between a positive voltage side and a negative voltage side of the current source step-down type chopper, or between the positive voltage side and the negative voltage side of the multiphase inverter, and the controller further controlling in the ignition mode, a voltage boosting operation according to short-circuit current which is made to flow in the current source step-down type chopper by the intermittent short-circuit control, so as to control output voltage to be applied to the plasma generator.