초록 ▼

A power supply system for providing uninterrupted AC power includes a first input port to which to couple AC input power at a specified RMS voltage level from a primary power source, a second input port to which to couple DC input power at a specified voltage level from a backup power source, and an

A power supply system for providing uninterrupted AC power includes a first input port to which to couple AC input power at a specified RMS voltage level from a primary power source, a second input port to which to couple DC input power at a specified voltage level from a backup power source, and an output port to which to connect a device to be powered. A fullwave rectifier generates a first direct current from the AC input power, and up-converter generates a second direct current from the DC input power at an RMS voltage level approximately equal to that of the AC input power, and a switching arrangement couples a selected one of the first and second direct currents to the output port according to whether the AC input power is stabilized or interrupted, so that the flow of current to the output port is periodically reversed thereby generate AC output power. Switching may by synchronized with each zero crossing of the AC input power. A microprocessor in one form of the invention generates a reference waveform, compares it to the waveform of the AC input power, and selects one of the first and second direct currents according to whether the AC input power is interrupted or stabilized.

대표청구항 ▼

A power supply system for providing uninterrupted AC power, comprising: a first input port to which to couple AC input power at a specified RMS voltage level from a primary power source, a second input port to which to couple DC input power at a specified voltage level from a backup power source, an

A power supply system for providing uninterrupted AC power, comprising: a first input port to which to couple AC input power at a specified RMS voltage level from a primary power source, a second input port to which to couple DC input power at a specified voltage level from a backup power source, and an output port to which to conenct a device to be powered; fullwave rectifying means for generating a first direct current from the AC input power; converting means for generating a second direct current from the DC input power at an RMS voltage level approximately equal to that of the AC input power; and switching means for coupling a selected one of the first and second direct currents to the output port according to whether the AC input power is stabilized or interrupted, and for periodically reversing the flow of the selected direct current to the output port to thereby generate AC output power; wherein the switching means includes waveform analyzing means for comparing the instantaneous voltage level of the AC input power at each of a plurality of phase angles with a corresponding reference value and generating an interruption-indicating control signal if the instantaneous voltage level at any one of the phase angles falls below the corresponding reference value.