Low power unity power factor ballast
May 11, 2014. 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 ReferencesEnergy conservation system using current control Electronic ballast with high power factor Power factor correction in electronic ballasts Fluorescent lamp ballast with high power factor Power factor correction circuit Fluorescent lamp system Electronic power factor correction for ballasts Inverter with power factor correction circuit Electronically power-factor-corrected ballast Apparatus for operating discharge lamp InventorsAssigneeApplicationNo. 241058 filed on 05/11/1994US Classes:315/247, With power factor control device315/209RPERIODIC SWITCH IN THE SUPPLY CIRCUITExaminersPrimary: Pascal, RobertAssistant: Gambino, Darius Attorney, Agent or FirmForeign Patent References
International ClassH05B 041/16AbstractAn inverter circuit operating from line utilizes minimum, lower rating switches to operate at higher frequency, while maintaining substantially unity power factor and lower input current harmonics. The input rectified DC is transferred to a storage capacitor using a buck-boost regulator in which the current in inductor is always maintained discontinuous and proportional to the instantaneous input voltage. Filtering this input current will give substantially sinusoidal current at the input. The second switch in the buck-boost regulator and an additional third switch contributes to the necessary half bridge for an inverter. The inverter, which can be self oscillating or driven from a control circuitry, can give higher frequency, high voltage AC output with ability to control the load power hence provide for dimming, e.g. for a fluorescent lamp. | |
