US 5,331,534 AGranted

Power supply apparatus

AssigneeTokyo Electric Co., Ltd.

InventorsShigesada Suzuki, Masahiro Sugiyama, Toshiyuki Hiraoka

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Abstract

A power supply apparatus has a full-wave rectifier for rectifying an AC voltage from an AC power source to output a DC pulsating voltage, and a high-frequency inverter which performs an oscillating operation to generate an output voltage. A first capacitor is connected between the output terminals of the full-wave rectifier, a diode is connected to one end of the first capacitor and is forward-biased with respect to the pulsating voltage from the full-wave rectifier, a second capacitor is connected in parallel with the first capacitor through the diode, and an oscillation circuit, including a series circuit formed of an inductor and a charging capacitor is connected in parallel with the second capacitor, for storing a DC voltage lower than a peak value of the pulsating voltage from the full-wave rectifier in the charging capacitor. The high-frequency inverter receives an input current supplied from the first and second capacitors when the pulsating voltage from the full-wave rectifier is higher than the charged voltage across the charging capacitor, receives an input current supplied from the oscillation circuit when the pulsating voltage from the full-wave rectifier is lower than the charged voltage across the charging capacitor, and performs an oscillating operation in the presence of the received input current.

Claims11

Dependent claims

A power supply apparatus comprising:

full-wave rectification means for rectifying an AG voltage supplied from an AC power source is output a DC pulsating voltage from first and second output terminals thereof, the potential of the first output terminal being set higher than the potential of the second output terminal;
a first capacitor coupled between said first and second output terminals of said rectification means, for storing a current from said rectification means;
a diode having an anode coupled to said first output terminal of said rectification means, for supplying a current from said first capacitor;
a second capacitor coupled to receive the current supplied through said diode, for storing the current received from said diode;
high-frequency inverter means, coupled between a cathode of said diode and said second output terminal of said rectification means, for receiving an input current supplied from said first and second capacitors when said diode is forward-biased and for receiving an input current from said second capacitor when said diode is reverse-biased, and for performing an oscillating operation in which the received input current is switched at a high frequency, and thereby producing an output voltage to be supplied to a load;
and
oscillation means, including a series circuit of an inductor and a third capacitor in which said series circuit is coupled in parallel with said second capacitor, for charging said third capacitor to a predetermined level lower than a peak level of the DC pulsating voltage which is output from said rectification means, and for causing said inductor and said second capacitor to oscillatory resonate under the voltage across said third capacitor when said DC pulsating voltage falls below the voltage across the third capacitor;
and
wherein a condition for resonance between said inductor and said second capacitor is set such that an amplitude of a resonant voltage is increased as the DC pulsating voltage output from said rectification means becomes lower than the voltage across said third capacitor.

6 more elements

A power supply apparatus comprising:

a first capacitor coupled in parallel with an AC power source, for storing a current from said AC power source;
full-wave rectification means coupled in parallel with said first capacitor, for rectifying an AC voltage from said first capacitor and to output a DC pulsating voltage from first and second output terminal thereof, the potential of said first output terminal being set higher than the potential of said second output terminal;
a second capacitor coupled between said first and second output terminals of said rectification means, for storing a current supplied through said rectification means;
high-frequency inverter means, coupled between said first and second output terminals of said rectification means, for receiving an input current supplied from said first and second capacitors when said rectification means is forward-biased and for receiving an input current supplied from said second capacitor when said rectification means is reverse-biased, and for performing an oscillating operation in which the received input current is switched at a high frequency, and thereby producing an output voltage to be supplied to a load;
and
oscillation means, including a series circuit of an inductor and a third capacitor in which said series circuit is coupled in parallel with said second capacitor, for charging said third capacitor to a predetermined level lower than a peak level of the DC pulsating voltage which is output from said rectification means, and for causing said inductor and said second capacitor to oscillatory resonate under the voltage across said third capacitor when said DC pulsating voltage falls below the voltage across said third capacitor;
and
wherein a condition for resonance between said inductor and said second capacitor is set such that an amplitude of a resonant voltage is increased as the DC pulsating voltage output from said rectification means becomes lower than the voltage across said third capacitor.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 07/977,557Filed 17 Nov 1992
Priority: JP 3-30494620 Nov 1991
Granted: 19 Jul 1994
Term ends: Not estimatedThe source records don’t support an estimate.

Classification8 codes

H02M 1/425
Arrangements for improving power factor of AC input: using a single converter stage both for correction of AC input power factor and generation of…
H02M 3/335
Using devices of a triode or a transistor type requiring continuous application of a control signal: using semiconductor devices only
H05B 41/28
In which the lamp is fed by power derived from DC by means of a converter, e.g. by high-voltage DC: using static converters
H02M 7/4818
Resonant converters: with means for adaptation of resonance frequency, e.g. by modification of capacitance or inductance of resonance circuits