Led lighting system and opertaing method for irradiation of plants

Abstract

An LED illumination system is operable to irradiate plant materials with photosynthetically active radiation. A lighting assembly includes a plurality of different LED types. Each LED lamp has a different spectral power matched to an absorption peak of the plant materials. All of the LED lamps of each different lamp type are driven by a different dedicated power source. Each power source can be independently modulated to vary the collective spectral power output of the LED illumination system. The lighting assembly includes fluid conduits disposed proximate to the LED lamps and a cooling fluid is flowed through the fluid conduits to removed thermal energy from the LED lamps.

1 - 22 . (canceled) 
     
     
         23 . A system for irradiating horticultural products with artificial light comprising:
 a lighting support structure comprising one or more lighting support beams each having a longitudinal length and a transverse width, wherein each lighting support beam includes a liquid cooling conduit enclosed by a conduit outer wall that is thermally conductively coupled with the lighting support beam;   one or more LED lamp support structures thermally conductively coupled with each lighting support beam, wherein each LED lamp support structure includes a plurality of LED lamp elements thermally conductively coupled with the LED lamp support structure; and,   a cooling conduit assembly comprising the liquid cooling conduit of each of the one or more lighting support beams fluidly coupled together between a fluid input port and a fluid output ports.   
     
     
         24 . The system of  claim 23  wherein each lighting support beam and the conduit outer wall corresponding therewith comprises a material having a thermal conductivity of 100 W/m° K or greater. 
     
     
         25 . The system of  claim 23  wherein the liquid cooling conduit enclosed by the conduit outer wall corresponding with each lighting support beam extends along the longitudinal length of the lighting support beam. 
     
     
         26 . The system of  claim 24  wherein each of the one or more lighting support beams is formed by an extruded U-shaped channel defining a base wall, extending along the longitudinal length and the transverse width, and two sidewalls extending from the base wall along the longitudinal length at opposing edges of the transverse width. 
     
     
         27 . The system of  claim 24  wherein each of the one or more lighting support beams comprises:
 a base wall that defines the transverse width and the longitudinal length; 
 two sidewalls extending from the same side of base wall along the longitudinal length; 
 wherein the base wall and the two side walls form three sides of a lamp cavity; and, 
 wherein each of the one or more LED lamp support structures is attached to the base wall inside the lamp cavity and oriented to direct radiant power emitted by the plurality of LED lamp elements supported by the one or more LED lamp support structures, out of the lamp cavity. 
 
     
     
         28 . The system of  claim 27  wherein the liquid cooling conduit formed by the conduit outer wall is outside the lamp cavity. 
     
     
         29 . The system of  claim 28  wherein the liquid fluid conduit enclosed by the conduit outer wall is formed with one of, a circular and a quadrilateral cross-section. 
     
     
         30 . The system of  claim 29  wherein the one or more lighting support beams each includes:
 a translucent cover, sealedly interfaced with each of the side walls to moisture and gas seal the lamp cavity along a longitudinal length thereof; 
 a first end cap, disposed at a first end of the lamp cavity and sealedly interfaced with, the base wall, the translucent cover and each of the two side walls, to moisture and gas seal the first end of the lamp cavity; 
 a second end cap, disposed at a second end of the lamp cavity, sealedly interfaced with the base wall, the translucent cover and each of the two side walls, to moisture and gas seal the second end of the lamp cavity. 
 
     
     
         31 . The system of  claim 30  further comprising one or more mirrored surfaces disposed inside the lamp cavity and oriented to reflect radiant power emitted by any of the plurality of LED lamps that impinges onto any one of the one or more mirrored surfaces out of the lamp cavity by the mirrored surface. 
     
     
         32 . The system of  claim 23  further comprising:
 a cooling loop comprising, the cooling conduit assembly, a cold side liquid conduit coupled to the fluid input port, a hot side liquid conduit coupled to the fluid output wherein the cold side liquid conduit and the hot side liquid conduit; 
 a fluid pump operated to circulate the first liquid cooling fluid through each of the cold side liquid conduit, the liquid cooling assembly, and the hot side liquid conduit and then back to the fluid pump; 
 one or more heat exchange elements disposed along the hot side liquid conduit between the liquid cooling assembly and the fluid pump, wherein each one or more heat exchange element is configured to transfer thermal energy from the first liquid cooling fluid to a second cooling fluid and wherein each one or more heat exchange elements includes a controllable fluid moving device moved at different rates of motion to control a flow rate of the second cooling fluid through the heat exchange element; 
 one or more thermal sensors positioned to sense a temperature corresponding with any one of, the first liquid cooling fluid, at one or more locations, a surface of the lighting assembly at one or more locations, and the second liquid cooling fluid at each of the one or more heat exchange elements; 
 one or more flow rate sensors positioned to sense flow rate corresponding with any one of the first liquid cooling fluid and the second cooling fluid; 
 a cooling system controller in communication with, the fluid pump, each second fluid moving device, each flow rate sensor, and each thermal sensor, wherein the cooling system controller is operated to independently vary flow rates of the first liquid cooling fluid and the second cooling fluid to maintain a desired temperature at a region of the lighting assembly. 
 
     
     
         33 . The system of  claim 32  wherein the second cooling fluid comprises one of a gaseous cooling fluid and a liquid cooling fluid. 
     
     
         34 . The system of  claim 32  wherein the cooling system controller is operated to maintain a temperature of the plurality of LED lamp elements, sensed by a thermal sensor disposed on a surface of the lighting assembly that is thermally conductively coupled to one of the lighting support beams at 60° C. or less. 
     
     
         35 . The system of  claim 34  wherein the cooling system controller is operated to maintain a temperature difference between the temperature of the plurality of LED lamp elements and a temperature of the first cooling fluid at an exit from the last of the one or more heat exchange elements, wherein the temperature difference is 8° C. or greater. 
     
     
         36 . The system of  claim 32  wherein the horticultural products are housed inside a structure and wherein one of the one or more heat exchange elements is, one of, disposed inside the structure and disposed outside the structure. 
     
     
         37 . A system for irradiating horticultural products with artificial light comprising:
 a lighting support structure comprising one or more lighting support beams;   one or more LED unit panels coupled to each of the one or more lighting support beams;   a plurality of individual LED lamps, comprising a plurality of different LED lamp types, coupled with each LED unit panel, wherein each different LED lamp type is configured to irradiate the horticultural products with a different spectral power;   a first power module comprising a DC power bus operated at substantially constant DC bus voltage to output a substantially constant DC bus power amplitude;   a plurality of second DC power modules electrically interfaced with the DC power bus to receive the DC power bus amplitude therefrom, wherein each second DC power module is independently operated to output a modulated DC power signal having a modulated power amplitude corresponding with driving the plurality of individual LED lamps of one of the plurality of LED lamp types to output a desired radiant power amplitude;   an electrical power interface structure comprising, for each different LED lamp type, conductive elements electrically interfaced between, the plurality of individual LED lamps of one of the plurality of LED lamp types, and one of the plurality of second DC power modules, wherein each second DC power module is electrically interfaced with the plurality of LED lamps of a different one of the plurality of LED lamp types;   an electronic controller comprising, a digital data processor, a memory module in communication with the digital data processor, and an operating program operated by the digital data processor to performing logical operations that provide command and control functions at least corresponding with irradiating the horticultural products with a desired spectral power and at a desired radiant power amplitude;   wherein the operating program operates to, apportion, according to the desired spectral power, the DC bus power amplitude to one or more of the plurality of LED lamp types, determine, for each second DC power module, a determined modulated power amplitude to be output therefrom to achieve the desired spectral power amplitude of the LED lamp type electrically interfaced with the corresponding second DC power module, and configure, each second DC power module to output the desired modulated power amplitude.   
     
     
         38 . The system of  claim 37  wherein each of the one or more lighting support beams has a longitudinal length and a transverse width and includes a liquid cooling conduit enclosed by a conduit outer wall that extends along the longitudinal length and that is thermally conductively coupled with the lighting support beam and wherein each one or more LED unit panel is thermally conductively coupled with the correspond lighting support beam further comprising:
 a cooling conduit assembly comprising the liquid cooling conduit of each of the one or more lighting support beams fluidly coupled together between a cold side liquid conduit and a hot side liquid conduit; 
 a fluid pump operated to circulate a first liquid cooling fluid through each of the cold side liquid conduit, the liquid cooling assembly, and the hot side liquid conduit and then back to the fluid pump; 
 one or more heat exchange elements disposed along the hot side liquid conduit between the liquid cooling assembly and the fluid pump, wherein each one or more heat exchange element is configured to transfer thermal energy from the first liquid cooling fluid to a second cooling fluid and wherein each one or more heat exchange elements includes a controllable fluid moving device operated to control a flow rate of the second cooling fluid through the heat exchange element; 
 one or more thermal sensors positioned to sense a temperature corresponding with any one of, the first liquid cooling fluid at one or more locations, a surface of the lighting assembly that is thermally conductively coupled with one of the unit panels, and the second liquid cooling fluid at each of the one or more heat exchange elements; 
 one or more flow rate sensors positioned to sense flow rate corresponding any one of the first liquid cooling fluid and the second cooling fluid; 
 a cooling system controller in communication with, the fluid pump, each second fluid moving device, each flow rate sensor and each thermal sensor, wherein the cooling system controller is operated to independently vary flow rates of the first liquid cooling fluid and the second cooling fluid to maintain a desired temperature at a region of the lighting assembly. 
 
     
     
         39 . The system of  claim 37  wherein the first power module comprises, an AC to DC power converter and a linear power regulator each operating to maintain the substantially constant DC bus voltage and output the substantially constant DC bus power amplitude. 
     
     
         40 . The system of  claim 37  wherein each of the plurality of second DC power modules comprises a current modulator operable by the electronic controller to modulate power amplitude of the modulated DC power signal using current modulation. 
     
     
         41 . The lighting assembly of  claim 37  wherein the plurality of different LED lamp types includes:
 a blue LED type having a main spectral power output in a spectral range of 425 to 470 nm driven by a first of the plurality of second DC power modules; 
 a red LED type having a main spectral power output in a spectral range of 620 to 650 nm driven by a second of the plurality of second DC power modules; and, 
 a deep red LED type having a main spectral power output in a spectral range of 660 to 680 nm driven by a third of the plurality of second DC power modules. 
 
     
     
         42 . The lighting assembly of  claim 40  wherein the plurality of different LED lamp types further includes a white LED type having a main spectral power output in a spectral range of 420 to 700 nm driven by a fourth of the plurality of second DC power modules. 
     
     
         43 . The lighting assembly of  claim 41  wherein the plurality of different LED lamp types further includes an ultraviolet LED type having a main spectral power output in a spectral range of 380 to 420 nm driven by a fifth of the plurality of second DC power modules. 
     
     
         44 . The lighting assembly of  claim 42  wherein the plurality of different LED lamp types further includes an infrared LED type having a main spectral power output in a spectral range of 730 to 770 nm driven by a sixth of the plurality of second DC power modules. 
     
     
         45 . The system of  claim 37  wherein plant materials of the horticultural products being irradiated have one or more spectral absorption peaks and wherein a spectral power output of at least a portion of the plurality of different LED lamp types is matched with one or more spectral absorption peaks of the plant materials. 
     
     
         46 . The lighting assembly of  claim 37  wherein the operating program operates to provide command and control functions corresponding with irradiating the horticultural products with a different spectral power during different growth stages of the horticultural products. 
     
     
         47 . The lighting assembly of  claim 37  wherein the operating program operates to provide command and control functions corresponding with irradiating the horticultural products with one of, a fixed spectral power, while temporally varying a radiant power amplitude of the irradiation over a temporal radiant power cycle, and with a fixed radiant power amplitude, while temporally varying a spectral power amplitude of the irradiation over a temporal spectral power cycle. 
     
     
         48 . A method for irradiating horticultural products with artificial light comprising the steps of:
 supporting, by a lighting support structure, comprising one or more lighting support beams, one or more LED unit panels coupled to each of the one or more lighting support beams, wherein each LED unit panel includes plurality of individual LED lamps comprises a plurality of different LED lamp types coupled thereto, wherein each different LED lamp type is configured to irradiate the horticultural products with a different spectral power;   outputting, by a first DC power module comprising a DC power bus, a substantially constant DC bus power amplitude at a substantially constant DC bus voltage;   powering, by the DC power bus, a plurality of second DC power modules electrically interfaced with the DC power bus to receive the DC bus power amplitude therefrom;   outputting, from each second DC power module, a modulated DC power signal at a power amplitude that corresponds with, driving, the plurality of individual LED lamps of one of the plurality of LED lamp types, to output a desired radiant power amplitude, wherein the modulated DC power amplitude output by each of the plurality of DC power modules is configured to drive individual LED lamps corresponding with different ones of the plurality of LED lamp types at different power amplitude levels;   distributing, from each second DC power module, to the plurality of individual LED lamps of one of the LED lamp types, the modulated DC power amplitude output thereby, wherein the modulated DC power amplitude output by each second DC power module is distributed to the plurality of LED lamps of a different one of the plurality of LED lamp types;   performing, by an operating program operating on an electronic controller comprising a digital data processor in communication with a memory, logical operations that provide command and control functions at least corresponding with controlling the first DC power module and the plurality of second DC power modules to irradiate the horticultural products with a desired spectral power;   apportioning, by the operating program, according to the desired spectral power, a portion of the DC bus power amplitude to one or more of the different LED lamp types;   determining, by the operating program, for each second DC power module, a determined modulated DC power amplitude value corresponding with the apportionment of the DC bus power amplitude to the LED lamp type corresponding with the second DC power module; and,   configuring, by the electronic controller, each second DC power module to output the determined modulated DC power amplitude value.   
     
     
         49 . The method of  claim 48  wherein the step of powering the DC power bus includes, converting an AC power signal, input to the first DC power module, to a DC power signal, and regulating the DC voltage and power amplitude. 
     
     
         50 . The method of  claim 49  wherein each of the plurality of second DC power modules comprises a current modulator that is independently operated by the electronic controller, wherein the current modulator operates to current modulate the substantially constant DC bus power amplitude received from the DC power bus and to output the determined modulated DC power amplitude value corresponding with the apportionment of the DC bus power amplitude to the LED lamp type corresponding with the second DC power module. 
     
     
         51 . The method of  claim 48 , wherein plant materials of the horticultural products being irradiated have one or more spectral absorption peaks, further comprising the step of matching a spectral power of least a portion of the plurality of different LED lamp types, included on each unit panel, with one or more spectral absorption peaks of plant materials. 
     
     
         52 . The method of  claim 48  wherein the operating program operates to provide command and control functions corresponding with irradiating the horticultural products with different spectral power outputs, further comprising the step of irradiating the horticultural products with the different spectral power outputs during different growth stages of the horticultural products. 
     
     
         53 . The method of  claim 48  wherein the operating program operates to provide command and control functions corresponding with irradiating the horticultural products with different spectral power outputs and with different radiant power outputs further comprising steps of;
 irradiating the horticultural products with a fixed spectral power while temporally varying a radiant power amplitude of the irradiation; and, 
 irradiating the horticultural products with a fixed radiant power amplitude while temporally varying a spectral power amplitude.