Back to results
US 4,045,722 AGranted
Power converter system
AssigneeHitachi, Ltd.
InventorKyozo Tachibana
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeHitachi, Ltd.
InventorKyozo Tachibana
Estimating the term…
A power converter system comprises a connection of a plurality of controlled rectifiers and a plurality of uncontrolled rectifiers, or a connection of only a plurality of controlled rectifiers. With an AC power supply as an input, the firing phase of the controlled rectifiers is controlled for conversion into a desired power. The commutating operation of the rectifiers is performed by utilizing the AC power supply. A retardation coil is connected to each of the rectifiers connected in series in the same polarity and making up an arm of the connection. The thus connected retardation coils are magnetically coupled with each other. The inductance of the commutating circuit is smaller when the output of the power converter is substantially maximum or minimum than the inductance when the output of the system is not maximum or minimum, thereby effectively reducing the higher harmonics components of the AC input current of the system at the time of commutating operation of the rectifiers without reduction of the utility of the converter.
A power converter system for converting an alternating current into a desired power, comprising a transformer, a rectifier means including a combination of a plurality of rectifier elements, said rectifier means being connected through said transformer to said AC power supply, said AC power supply being utilized at the same time as a commutation power source for said rectifier elements, and a plurality of retardation coils connected in series with said rectifier elements at the AC power supply side of said rectifier means, said retardation coils being magnetically coupled with each other.
A power converter system comprising a rectifier circuit means whose AC input terminals are connected to an AC power supply through a transformer, said rectifier circuit means including a bridge connection of a plurality of rectifier elements, said AC power supply being utilized as a commutation power source for said rectifier elements, a plurality of retardation coils inserted in selected ones of the arms of said bridge connection respectively and correspondingly to the rectifier elements which are connected in series to each other to constitute said selected one arm, said retardation coils being magnetically coupled with each other, and another retardation coil inserted between a predetermined one of the two end terminals of said transformer and the AC input terminal of said rectifier circuit which is connected to said predetermined one end terminal.
A power converter system comprising an AC power supply, a transformer having a primary winding connected to said AC power supply and having a plurality of secondary windings, a plurality of rectifier circuit units each unit including a bridge connection of a plurality of rectifier elements, the DC output sides of the respective rectifier circuit units being connected in series with each other, and a plurality of retardation coils inserted in selected ones of the arms of selected ones of said rectifier units respectively and correspondingly to the rectifier elements which are connected in series to each other to constitute said selected one arm, said retardation coils being magnetically coupled with each other.
Dependencies are inferred from the claim text.