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US 7,888,886 B2Granted
Universal line voltage dimming method and system
AssigneeKoninklijke Philips Electronics N.V.
InventorMingliang Wu
Life of this patent
Estimating the term…
Abstract
A universal line voltage dimming method and system, with a control circuit for an electronic ballast including an on-time converter (50) generating an on-time signal (54) in response to a sensed phase-controlled power signal (52), and a micro-processor (56) responsive to the on-time signal (54) and generating a dimming control signal (58). A lamp control method for an electronic ballast includes sensing phase-controlled power, determining on-time for the sensed phase-controlled power, and controlling lamp dimming in response to the on-time.
Claims22
A control circuit for an electronic ballast, the circuit comprising:
- an on-time converter generating an on-time signal in response to a sensed phase-controlled power signal;
- and
- a microprocessor responsive to the on-time signal and generating a dimming control signal, wherein the on-time converter comprises:
- a rectifier operably connected to receive the sensed phase-controlled power signal;
- a clipping circuit operably connected to the rectifier;
- and
- a switching circuit operably connected to the clipping circuit through an isolator, the switching circuit being operably connected to transmit the on-time signal.
4 more elements
A control circuit for an electronic ballast, the circuit comprising:
- an on-time converter generating an on-time signal in response to a sensed phase-controlled power signal;
- a microprocessor responsive to the on-time signal and generating a dimming control signal;
- and
- a filter operably connected to receive a pulsed dimming control signal from the microprocessor and to generate the dimming control signal.
1 more element
A control circuit for an electronic ballast, the circuit comprising:
- an on-time converter generating an on-time signal in response to a sensed phase-controlled power signal;
- and
- a microprocessor responsive to the on-time signal and generating a dimming control signal;
- wherein the on-time converter comprises:
- a scaling circuit operably connected to receive the sensed phase-controlled power signal;
- and
- a comparator operably connected to the scaling circuit, the comparator transmitting the on-time signal.
4 more elements
A lamp control method for an electronic ballast, the method comprising:
- sensing phase-controlled power;
- determining on-time for the sensed phase-controlled power;
- and
- controlling lamp dimming in response to the on-time, wherein the determining step comprises:
- rectifying the sensed phase-controlled power to generate rectified phase-controlled power;
- clipping the rectified phase-controlled power to generate an on-time pulse;
- measuring duration of the on-time pulse to determine the on-time.
4 more elements
A lamp control method for an electronic ballast, the method comprising:
- sensing phase-controlled power;
- determining on-time for the sensed phase-controlled power;
- and
- controlling lamp dimming in response to the on-time, wherein the determining step comprises:
- rectifying the phase-controlled power to generate rectified phase-controlled power;
- clipping the rectified phase-controlled power to generate a series of on-time pulses;
- measuring duration for each of the series of on-times pulses;
- and
- averaging the durations to determine the on-time.
6 more elements
A lamp control method for an electronic ballast, the method comprising:
- sensing phase-controlled power;
- determining on-time for the sensed phase-controlled power;
- and
- controlling lamp dimming in response to the on-time, wherein the determining comprises:
- scaling the phase-controlled power to generate scaled phase-controlled power;
- and
- comparing the scaled phase-controlled power to a predetermined level to determine the on-time.
4 more elements
A lamp control system comprising:
- means for sensing phase-controlled power;
- means for determining on-time for the sensed phase-controlled power;
- and
- means for controlling lamp dimming in response to the on-time, wherein the means for determining comprises:
- means for rectifying the sensed phase-controlled power to generate rectified phase-controlled power;
- means for clipping the rectified phase-controlled power to generate an on-time pulse;
- means for measuring duration of the on-time pulse to determine the on-time.
4 more elements
A lamp control system comprising:
- means for sensing phase-controlled power;
- means for determining on-time for the sensed phase-controlled power;
- and
- means for controlling lamp dimming in response to the on-time, wherein the means for determining comprises:
- means for rectifying the sensed phase-controlled power to generate rectified phase-controlled power;
- means for clipping the rectified phase-controlled power to generate a series of on-time pulses;
- means for measuring duration for each of the series of on-times pulses;
- and
- means for averaging the durations to determine the on-time.
6 more elements
A lamp control system comprising:
- means for sensing phase-controlled power;
- means for determining on-time for the sensed phase-controlled power;
- and
- means for controlling lamp dimming in response to the on-time, wherein the means for determining comprises:
- means for scaling the phase-controlled power to generate scaled phase-controlled power;
- and
- means for comparing the scaled phase-controlled power to a predetermined level to determine the on-time.
4 more elements
A control circuit for an electronic ballast having a boost/power factor controller, the circuit comprising:
- a line voltage detector generating a line voltage signal in response to a sensed phase-controlled power signal;
- a microprocessor being responsive to the line voltage signal and generating a capacitance selector signal;
- a capacitance circuit being responsive to the capacitance selector signal to adjust capacitance of the boost/power factor controller;
- and
- an on-time converter, the on-time converter generating an on-time signal in response to the sensed phase-controlled power signal;
- wherein the microprocessor is responsive to the on-time signal to generate a dimming control signal, and wherein the on-time converter comprises:
- a rectifier operably connected to receive the sensed phase-controlled power signal;
- a clipping circuit operably connected to the rectifier;
- and
- a switching circuit operably connected to the clipping circuit through an isolator, the switching circuit being operably connected to transmit the on-time signal.
7 more elements
A lamp control method for an electronic ballast, the method comprising:
- sensing a phase-controlled power;
- determining line voltage for the sensed phase-controlled power;
- adjusting boost/power factor controller capacitance in response to the line voltage;
- determining on-time for the sensed phase-controlled power;
- and
- controlling lamp dimming in response to the on-time,
- wherein the determining step comprises:
- rectifying the sensed phase-controlled power to generate rectified phase-controlled power;
- clipping the rectified phase-controlled power to generate an on-time pulse;
- measuring duration of the on-time pulse to determine the on-time.
7 more elements
Dependencies are inferred from the claim text.