Power supply with improved power factor correction
Patent 5003454 Issued on March 26, 1991. Estimated Expiration Date: 
January 9, 2010. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
January 9, 2010. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesAC to DC power converter with integrated line current control for improving power factor Current mode converter with controlled slope compensation AC to DC converter with unity power factor Patent #: 4940929 InventorApplicationNo. 462682 filed on 01/09/1990US Classes:363/81, By rectifier323/222, Using choke and switch across source363/89With transistor control means in the line circuitExaminersPrimary: Beha, William H. Jr.Attorney, Agent or FirmForeign Patent References
International ClassesH02M 007/06G05F 001/70 AbstractA regulated voltage converter circuit includes a storage inductor and a controlled semiconductor switch connected in series circuit to a pair of input terminals that supply a full wave rectified voltage of a sinusoidal 60 Hz AC input voltage. A power factor amplifier receives a divided part of the rectified voltage and produces an output control voltage VM of a predetermined waveform (FIG. 2c). A comparison circuit compares the control voltage VM with a ramp voltage that is proportional to the current flowing through the semiconductor switch. The comparison circuit supplies PWM pulses to a control electrode of the semiconductor switch so as to regulate the output voltage of the converter circuit. The control voltage (VM) waveform is chosen so as to produce near unity power factor correction at the input of the converter circuit. | |
