Light-generating system
View Patent ↗A light-generating system including a LED load array having a number of light-emitting diodes, and a heat sink on which the LED load array is mounted. The system also includes a power control unit electrically connected to the power source and the LED load array, for converting input electrical power to output electrical power and controlling voltage and current of the output electrical power provided to the LED load array, and a temperature detector subassembly adapted for sensing a heat sink temperature of the heat sink. The temperature detector subassembly monitors the heat sink temperature and transmits a control signal to the power control unit upon determining that the heat sink temperature differs from a preselected temperature by more than a preselected minimum difference. Upon receipt of the control signal, the power control unit changes the voltage of the output electrical power accordingly.
1. A light-generating system for consuming input electrical power from a power source to generate light, the light-generating system comprising:
a LED load array comprising a plurality of light-emitting diodes, the light-emitting diodes having an operating temperature when energized;
a heat sink on which the LED load array is mounted, the heat sink being adapted for absorbing and dissipating heat energy generated by the light-emitting diodes when energized, the heat sink comprising:
a body portion to which the light-emitting diodes are attached;
a finned portion connected to the body portion, for dissipation of heat energy transferred thereto at least partially via conduction from the light-emitting diodes, to cool the light-emitting diodes;
a power control unit electrically connected to the power source and the LED load array, for converting the input electrical power to an output electrical power and controlling voltage and current of the output electrical power provided by the power control unit to the LED load array;
a temperature detector subassembly operatively connected to the power control unit, the temperature detector subassembly being adapted for sensing a heat sink temperature of the heat sink at least one predetermined location thereon;
the temperature detector subassembly being adapted to compare the heat sink temperature to at least one preselected temperature within a preselected temperature range, and to transmit a control signal to the power control unit upon determining that the heat sink temperature differs from said at least one preselected temperature by more than at least one preselected minimum difference; and
upon receipt of the control signal, the power control unit changes the voltage of the output electrical power, to modulate the performance of the light-emitting diodes such that the heat sink temperature is within the preselected temperature range.
2. A light-generating system according to claim 1 in which the power control unit comprises:
a microprocessor; and
a current sensor, for determining current data associated with the output electrical power and communicating the current data to the microprocessor.
3. A light-generating system according to claim 1 additionally comprising an ambient light controller for controlling the electrical power provided to the LED load array, in indirect proportion to ambient light.
4. A light-generating system according to claim 1 in which:
said at least one preselected temperature comprises an upper limit preselected temperature and a lower limit preselected temperature; and
said at least one preselected minimum difference comprises an upper limit minimum difference and a lower limit minimum difference.
5. A light-generating system according to claim 4 in which, upon the temperature detector subassembly determining that the heat sink temperature is greater than the upper limit preselected temperature by at least the upper limit minimum difference, the temperature detector subassembly sends the control signal to the power control unit, for causing the power control unit to decrease the output electrical power to lower the heat sink temperature until the heat sink temperature is within the preselected temperature range.
6. A light-generating system according to claim 5 in which the control signal causes the voltage of the output electrical power to decrease to an extent required by the control signal.
7. A light-generating system according to claim 4 in which, upon the temperature detector subassembly determining that the heat sink temperature is less than the lower limit preselected temperature by at least the lower limit minimum difference, the temperature detector subassembly sends the control signal to the power control unit, for causing the power control unit to increase the output electrical power to raise the heat sink temperature until the heat sink temperature is within the preselected temperature range.
8. A light-generating system according to claim 7 in which the control signal causes the voltage of the output electrical power to increase to an extent required by the control signal.