Apparatus and methods for reducing the power consumption of fluorescent lights
AssigneePyramid Technologies LLC
InventorGeorge Bucci
Life of this patent
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Abstract
Systems for reducing the power consumption of fluorescent lights are provided. The systems can be used in new construction as well as retrofitted into existing buildings employing overdriven fluorescent lights without significantly affecting the operation of utility power lines. In preferred embodiments, the systems provide substantially constant light output during start-up and low voltage conditions.
Claims27
Apparatus for controlling the delivery of electrical power to fluorescent light fixtures, said electrical power having a phase which has a substantially sinusoidal waveform which has repetitive zero crossings separated from one another by a nominal time period T, said apparatus comprising:
- (a) a plurality of controllers;
- and
- (b) a plurality of electronic switches;
- wherein during use of the apparatus:
- (i) each electronic switch is in series with at least one fluorescent light fixture;
- (ii) each electronic switch is operatively connected to a controller that sends an electronic signal to the switch to cause the switch to transition between non-conducting and conducting states, said electronic signal being sent during each half cycle of the phase's waveform at a switching time t(j) measured from the waveform's zero crossing, where j indicates the controller sending the electronic signal and where 0≦t(j)≦T for each j;
- and
- (iii) for at least two of the controllers j 1,j2, on at least a statistical basis, t(j1)≠t(j2).
An assembly for controlling the delivery of electrical power to one or more fluorescent light fixtures, said one or more fluorescent light fixtures being on the same phase of the electrical power and the electric power of said phase having a substantially sinusoidal waveform which has repetitive zero crossings separated from one another by a nominal time period T, said assembly comprising:
- (a) an electronic switch which during use is in series with the one or more fluorescent light fixtures, and
- (b) a controller which during use is operatively connected to the electronic switch for sending an electronic signal to the switch to cause the switch to transition between non-conducting and conducting states;
- wherein:
- (i) the electronic signal of the controller is repetitively sent to the electronic switch during each half cycle of the waveform at a switching time t measured from the zero crossing;
- and
- (ii) t satisfies the relationship:
- t=tnom+tvar
- where tnom is a nominal value for the switching time and tvar has a magnitude and/or sign that varies with time so as to modulate tnom.
An assembly for controlling the delivery of electrical power to one or more fluorescent light fixtures, said one or more fluorescent light fixtures being on the same phase of the electrical power and the electric power of said phase having a substantially sinusoidal waveform which has repetitive zero crossings separated from one another by a nominal time period T, said assembly comprising:
- (a) an electronic switch which during use is in series with the one or more fluorescent light fixtures, and
- (b) a controller which during use is operatively connected to the electronic switch for sending an electronic signal to the switch to cause the switch to transition between non-conducting and conducting states;
- wherein:
- (i) the electronic signal of the controller is repetitively sent to the electronic switch during each half cycle of the waveform at a switching time t measured from the zero crossing;
- and
- (ii) t has a mean value during steady state tmean-ss and a mean value during start-up tmean-start, where:
- tmean-start<tmean-ss.
An assembly for controlling the delivery of electrical power to one or more fluorescent light fixtures, said one or more fluorescent light fixtures being on the same phase of the electrical power and the electric power of said phase having a substantially sinusoidal waveform which has repetitive zero crossings separated from one another by a nominal time period T, said assembly comprising:
- (a) an electronic switch which during use is in series with the one or more fluorescent light fixtures, and
- (b) a controller which during use is operatively connected to the electronic switch for sending an electronic signal to the switch to cause the switch to transition between non-conducting and conducting states;
- wherein:
- (i) the electronic signal of the controller is repetitively sent to the electronic switch during each half cycle of the waveform at a switching time t measured from the zero crossing;
- and
- (ii) t has a mean value during steady state tmean-ss and at least one mean value during low voltage conditions tmean-lowvolt, where:
- tmean-lowvolt<tmean-ss.
Dependencies are inferred from the claim text.