US 6,069,811 A · DC power supply apparatus

Abstract

A DC power supply apparatus includes a rectifier circuit which rectifies an input commercial AC voltage. The rectifier output voltage is smoothed in a smoothing capacitor. The DC voltage from the capacitor is converted to a high-frequency voltage in an inverter. The high-frequency voltage from the inverter is voltage-transformed by a transformer into a voltage-transformed, high-frequency voltage, which is then converted back into a DC voltage in a high-frequency-to-DC converter circuit. When an input commercial AC voltage is applied to the DC power supply apparatus, a pre-charging circuit pre-charges the smoothing capacitor from the input AC voltage. If a voltage having a magnitude larger than a prescribed value is applied to the DC power supply apparatus, an overvoltage protection circuit renders the rectifier circuit and the pre-charging circuit inoperative.

Claims8

Dependent claims

A DC power supply apparatus comprising:

a rectifier circuit for rectifying an input commercial AC voltage;
a smoothing capacitor for smoothing a rectified output voltage from said rectifier circuit;
a DC-to-high-frequency converter circuit for converting a smoothed DC voltage from said smoothing capacitor into a high-frequency voltage;
a transformer for voltage-transforming the high-frequency voltage supplied from said DC-to-high-frequency converter circuit;
a high-frequency-to-DC converter circuit for converting a voltage-transformed, high-frequency voltage supplied from said transformer into a DC voltage;
a pre-charging circuit for pre-charging, when said input commercial AC voltage is applied to said DC power supply apparatus, said smoothing capacitor from the input commercial AC voltage;
and
an overvoltage protection circuit for rendering said pre-charging circuit and said rectifier circuit inoperative when said input commercial AC voltage is a voltage having a magnitude larger than a prescribed value.

5 more elements

A DC power supply apparatus comprising:

a rectifier circuit for rectifying an input commercial AC voltage;
a smoothing capacitor for smoothing a rectified output voltage from said rectifier circuit;
a DC-to-high-frequency converter circuit for converting a smoothed DC voltage from said smoothing capacitor into a high-frequency voltage;
a transformer for voltage-transforming the high-frequency voltage supplied from said DC-to-high-frequency converter circuit;
a high-frequency-to-DC converter circuit for converting a voltage-transformed, high-frequency voltage supplied from said transformer into a DC voltage;
a pre-charging circuit for pre-charging, when said input commercial AC voltage is applied to said DC power supply apparatus, said smoothing capacitor from the input commercial AC voltage;
and
an overvoltage protection circuit for decoupling said pre-charging circuit and said rectifier circuit from said input commercial AC voltage when said input commercial AC voltage is a voltage having a magnitude larger than a prescribed value.

5 more elements

Dependencies are inferred from the claim text.

DC power supply apparatus

Life of this patent

DC power supply apparatus

Life of this patent

Abstract

Claims8