High-power factor circuit for energizing gas discharge lamps
First Claim
Patent Images
1. A circuit for powering a gas discharge lamp from a source of a first frequency AC power comprising:
- a first rectifier for converting the first frequency AC power into a first DC power;
a capacitor coupled to the rectifier for storing the DC power as energy;
a driver having a driver input and a driver output, which produce an electrically symmetric output, the driver input coupled to the capacitor for converting the energy stored in the capacitor into a second frequency AC power;
a second rectifier having a second rectifier input and a second rectifier output, the second rectifier input coupled to the inverter output for converting some of the second frequency AC power into a second DC power;
voltage control means for adjusting the voltage of the second frequency AC power at the input of the second rectifier; and
impedance control means for controlling the impedance of the second rectifier.
2 Assignments
0 Petitions
Accused Products
Abstract
A circuit for powering a gas discharge lamp from a source of a first frequency AC power has a a first rectifier for converting the first frequency AC power into a first DC power, a capacitor and driver for converting the DC power to a second frequency AC power. A second rectifier is used to increase the power factor for the circuit. A control is provided to disable the second rectifier if the lamp is removed from the circuit.
-
Citations
19 Claims
-
1. A circuit for powering a gas discharge lamp from a source of a first frequency AC power comprising:
-
a first rectifier for converting the first frequency AC power into a first DC power; a capacitor coupled to the rectifier for storing the DC power as energy; a driver having a driver input and a driver output, which produce an electrically symmetric output, the driver input coupled to the capacitor for converting the energy stored in the capacitor into a second frequency AC power; a second rectifier having a second rectifier input and a second rectifier output, the second rectifier input coupled to the inverter output for converting some of the second frequency AC power into a second DC power; voltage control means for adjusting the voltage of the second frequency AC power at the input of the second rectifier; and impedance control means for controlling the impedance of the second rectifier. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A method of powering a gas discharge lamp with a circuit from a source of AC power comprising the steps of:
-
rectifying the AC power at a first frequency into a first DC power; storing the first DC power as energy in a capacitor; inverting the stored energy into AC power at a second frequency with a parallel resonant tank circuit; energizing the lamp with the some of the AC power at a second frequency; rectifying with a rectifier some of the AC power at a second frequency into a second DC power; using the second DC power to control the power factor of the circuit; and controlling the impedance of the rectifier. - View Dependent Claims (8, 9, 10, 11, 12, 13)
-
-
14. A circuit for correcting the power factor of a power line driven gas discharge lamp power source, having a resonant capacitor and resonant inductor connected together in parallel, the resonant inductor having at least two auxiliary windings and operated on by a driving circuit so that an alternating current flows around the circuit thus formed;
- characterized in that one auxiliary winding is used for driving a lamp and another auxiliary winding is connected by a feedback circuit, the feedback circuit comprising a capacitor in series with a full bridge rectifier, to cause the line current drawn from the power line to be proportional to, in phase with, and have the same waveform shape as the power line voltage.
- View Dependent Claims (15, 16, 17)
-
18. A circuit for correcting the power factor of a power line driven gas discharge lamp power source, having a resonant capacitor and resonant inductor connected together in parallel, the resonant inductor having at least two auxiliary windings and operated on by a driving circuit so that an alternating current flows around the circuit thus formed, and a control configured to sense whether a load is attached to the circuit and to disable a feedback circuit if the load is not attached to the circuit:
- characterized in that one auxiliary winding is used for driving a lamp and another auxiliary winding is connected by the feedback circuit to cause the line current drawn from the power line to be proportional to, in phase with, and have the same waveform shape as the power line voltage.
- View Dependent Claims (19)
Specification