Title:
HIGH FREQUENCY POWER SUPPLY DEVICE
Document Type and Number:
Japanese Patent JP2016171639
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To solve such a problem that since the impedance and power factor of the load of a high frequency power supply device changes in a wide range, a thyristor rectifier is required to feed a large current when the inverter output voltage is low, and thereby a thyristor rectifier of large current capacity is required.SOLUTION: An inverter control circuit is provided with means for preventing a DC current flowing through a thyristor rectifier from exceeding a preset DC current upper limit, and means for controlling the inverter with a conduction width narrower than 180 degree when the DC current exceeds the upper limit. When the power supplied to the load is constant and the load is reduced, the inverter control circuit is required to reduce the DC voltage and to increase the DC current, and thereby the DC current is provided with an upper limit and prevented from exceeding the upper limit.SELECTED DRAWING: Figure 1
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Inventors:
WATASE YUKI
HIRAMATSU MASANORI
HIRAMATSU MASANORI
Application Number:
JP2015048914A
Publication Date:
September 23, 2016
Filing Date:
March 12, 2015
Export Citation:
Assignee:
MEIDENSHA ELECTRIC MFG CO LTD
International Classes:
H02M7/48; H02M7/155
Attorney, Agent or Firm:
Hiromichi Kobayashi
Uzawa Hidehisa
Uzawa Hidehisa