DESC:FFIELD OF THE INVENTION:

The present invention describes a methodology of realising cost-effective and energy efficient LED based street or outdoor lighting solutions, particularly of relevance to perform in the Indian context of power conditions - urban or rural - like wide input voltage variations, spikes and surges, improper earthings, accidental high tension wire drops and the like. The invention makes use of the thermo plastic technology to improve the housing designs of the LED Luminaires by embedding the Die-cast aluminium or extruded plate type aluminium housings within a thermo plastic exterior to take advantage of the characteristics of light weight and effective thermal management of the thermo plastics. It is proposed to achieve this objective through a right mix of (i) LED technologies (ii) LED driver technologies (iii) modular mechanical and packaging designs for improved manufacturability and productivity (iv) embedded local intelligence built around sensors, data loggers, webcams and microcontrollers (v) networking & communication interfaces and (vi) the application software. Custom packaged LED chips, AC controlled LED Driver circuits, Modular architecture, biodegradable thermo plastic luminaire housings and integrally formed sheet of lenses for secondary optics are deployed in realising cost-effective solutions for any specification / application. Waste disposal is also safer due to the biodegradable components - a green energy initiative. The LED Street lighting solutions proposed, not only deliver the prime functionality of outdoor lighting with efficiency, for both the environments - the protected (Tunnel lighting, Parking bay lighting etc) as well as the exposed (Street lighting, Yard Lighting, High bay lighting etc) but also provide ready adaptability into a smart grid environment for execution of supervisory functions like Operations & Maintenance (O&M), Energy Management etc by the Utility service providers with the help of the IP enabled access through networking and communication facilities. The lighting enclosure can optionally accommodate more sensors including a camera to provide additional services like surveillance, weather reporting and visual snapshots of events or incidents etc to aid the Utility Managers. These lighting solutions are expected to greatly help the lighting infrastructure in India in terms of manufacturability, economy, safety, maintainability, automation, energy saving and eco-friendliness.

PRIOR ART:

LED Street Lights have been proved to be superior to conventional street lights viz Mercury, Sodium Vapour or Metal Halide lamps etc, in terms of energy efficiency, long life (of the order of 50,000 hours), freedom from burn-outs, and minimal maintenance and replacements. The early models have essentially demonstrated the energy efficiency concept that LED street lights consume less than half the power as compared to the conventional light sources in providing the same amount of light output. They addressed the basic functional requirements covering light (lux) levels, energy efficiency, long life and thermal management.

Subsequent efforts went in the direction of defining new dimensions for performance. They are in the form of further improvements in the operational aspects like:

- power saving through Auto On / Off, programmable dimming and occupancy or proximity based dimming with in-built and remote control features;

- networking of street lights enabling wired or wireless communication between the lights as well as between the lights and a central monitoring station for remote control;

- web enabled access to individual lights or a cluster of lights to monitor/detect malfunctioning / isolate or repair / report to the concerned; and

- improving the manufacturability and yield to offer cost-effective total solutions.

Accordingly, intelligent, interactive and remotely operable LED street lights with networking and communication facilities enabling access to the luminaires through internet (IP) have been developed.

The significant work done by the inventor in respect of LED Lighting is evident from the following co-pending patent applications by the inventor, covering the technological and operational aspects in great depth:

Outdoor Lighting including Street Lights:
1 Interactive and intelligent street light of LED Light sources 2219/CHE/2009 Dt:14-09-2009
2 A LED based intelligent luminaire system for illuminating targets such as Billboards and the like 2774/CHE/2009
Dt:11.11.2009
3 An Integrated LED based Solar Street Light Luminaire Assembly 3207/CHE/2010A Dt:28.10.2010
4 A LED based (Extrusion type Street) lighting product assembly 4197/CHE/2014
Dt: 27.08.2014

Indoor Lighting including Portables:
5 Solar Rechargeable LED Lantern 2062/CHE/2008 25-08-2008
6 LEDMax- PetroMax like portable high illumination lamp outfit with solid state Light Emitting Diodes (LEDs) 2363/CHE/2009
29-09-2009
7 LED based Mushroom light to replace the conventional table light 848/KOL/2010
02.08.2010
8 LED based bulb to retrofit into the conventional lighting fixture of incandescent or CFL bulb 849/KOL/2010
02.08.2010
9 LED Based Extendable and configurable lighting system / DC or Solar operated tube lights 2713/CHE/2010
15.09.2010
11 LED based tube to retrofit in the conventional fluorescent tube lighting fixture - LEDTube 282/CHE/2011 31.01.2011
12 LED Recessed Down Light 442/CHE/2011
15.02.2011
13 LED Troffer Light 924/CHE/2011
24.03.2011
14 Solar based LED Home Lighting System 2469/CHE/2011 19.07.2011
15 Intelligent Building Lighting System 2912/CHE/2011
25.08.2011
16 Simple switch-operated dimmable lights 4499/CHE/2011 21.12.2011
17 Utilisation of rectified AC for LED driving in Bulb and the like 6202/CHE/2013 31.12.2013

Grid based LED Street lights included in the prior art above (2219/2009 , 4197/2014) addressed the basic functional requirements like light (lux) levels, energy efficiency, long life, thermal management and environmental protection; and advanced features like Auto On / Off, programmable dimming, occupancy or proximity based dimming etc for power saving; networking of street lights enabling communication - wired or wireless - between the lights as well as between the lights and a central monitoring station for remote control; web enabled access to individual lights or a series of lights to monitor / detect malfunctioning / isolate or repair / report to the concerned; and improving the manufacturability and yield to offer cost-effective solutions.

A Networked Street Light Control System with the communication interfaces for centralised monitoring and control have also been included as reproduced in figure 1.

OBJECT OF THE INVENTION:

The object of this invention is to develop cost effective, energy efficient LED based light solutions, particularly suited to perform in the critical or erratic power conditions obtaining in the rural or urban parts of India, with requisite functionalities and interactive capabilities needed for the luminaire to be integrated into a futuristic 'smart grid environment'.

The invention makes use of the thermo plastic technology to improve the housing designs of the LED Luminaires by embedding the Die-cast aluminium or extruded plate type aluminium housings within a thermo plastic exterior to take advantage of the characteristics of light weight and effective thermal management of the thermo plastics.

Yet another objective of this invention is that these lighting solutions are expected to greatly help the lighting infrastructure in India in terms of manufacturability, economy, safety, maintainability, automation, energy saving and eco-friendliness.

SUMMARY OF THE INVENTION:

Thus according to the basic aspect of the present invention, there is provided a light emitting diode (LED) based lighting fixture for outdoor applications comprising

a light supporting housing for containing one or more LED PCB together with optical lenses forming an integrally formed sheet architecture;

said LED PCBs with the integral optical lenses are assembled in said light supporting housing in modular manner for variable illumination and disposed in one side of the light supporting housing spaced apart from each other with operational gap between two consecutive LED PCBs favouring dissipation of the heat form the LEDs while operating involving integral solid shaped light weighted heat dissipating light supporting housing.

According to another aspect in the present LED based lighting fixture for outdoor applications, the light supporting housing comprises surface fins on the opposite side of the LED PCBs to facilitate the heat dissipation.

According to a further aspect in the present LED based lighting fixture for outdoor applications, electronics including LED driver /power supply and embedded systems are housed in a compartment in the housing next to the LED PCB section.

According to a further aspect in the present LED based lighting fixture for outdoor applications, number of the said LED PCBs in the light supporting housing is determined to get the desired illumination by involving the single light supporting housing.

According to yet another aspect in the present LED based lighting fixture for outdoor applications, the housing is essentially formed by involving thermo plastics for use in lighting applications.

According to another aspect in the present LED based lighting fixture for outdoor applications, the housings comprises a thermoplastic layer over die-cast aluminium or extruded plate type housings for facilitating effective thermal management in ventilating the heat developed inside into the ambient to keep the LED junction temperatures within LED operational limits and ensure long life preferably 50000 hours for LED light sources.

According to another aspect in the present LED based lighting fixture for outdoor applications, the housings thermoplastic formulation essentially contains lactic acid having characteristics of biodegradability, proper thermal resistance and mouldablility into rigid solid shape to accommodate the LED PCB assembled with other components.

According to another aspect in the present LED based lighting fixture for outdoor applications, the housing is light weighted and comprises fixing clamp for easily retrofitting in any bracket/ pole arms of any size without straining them with weight.

According to a further aspect, the present LED based lighting fixture for outdoor applications comprises a centralized Control & Monitoring systems for using in street lighting applications and facilitating one or more from (i) energy savings, (ii) energy optimization, (iii) health monitoring of the street lights for repair and replacement purposes, (iv) tracking of electrical parameters for safety of the LEDs and (v) alerting concerned recipients in event of any abnormal developments in line conditions.

According to yet another aspect in the present LED based lighting fixture for outdoor applications, the CCMS facilitates automatic on/off functions to ensure switching-on and switch-off functions of the street lighting system based on either ambient conditions or scheduled time frames and also enabling automatic dimming in a programmed way at prescribed times or in a prescribed profile to ensure energy savings and energy optimization.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS:

Figure 1 shows networked street lighting control system embodiment.

Figure 2 shows a high end LED based light luminaire embodiment in accordance with present invention.

Figure 2-A shows a high end LED based light luminaire embodiment – assembly process in accordance with present invention.

Figure 3 shows low end LED based light luminaire embodiment in accordance with present invention.

Figure 4 shows LED light module – Modular architecture in accordance with the present invention.

Figure 5 and 6 show the external and internal schematic illustration of the present Centralized Control & Monitoring Systems (CCMS) for Smart Grid Applications.

DETAILED DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS:

The present invention extensively makes use of the significant work done by the inventor and as reported in prior art for realising cost-effective LED lighting solutions.

The operational and supervisory functions and capabilities covered in the prior art and relevant for future are:

? Specified / Targeted Lux levels
? Long Life
? Auto ON / OFF with sensors
? Programmable dimming for energy conservation
? Proximity and Occupancy sensor based light controls
? Protection for over-temperature & short–circuits
? Interactive monitoring and control through networking
? Effective thermal management
? Ruggedised with IP66/67 rated Environmental protection
? Embedded Local intelligence for controls & communications
? IP enabled Remote access and control
? Networking - Connectivity between lights up to a local concentrator and from concentrator to a centralised monitoring station
? Wireless Connectivity by means of Zigbee, GPRS, GSM techniques

The salient features of the present invention are:

? Tangible benefits to the end user
? Efficient and safe working in the Indian power conditions of wide input variations like 90-305V, fluctuations, surges, spikes , improper earthing / grounding etc.
? Cost-effectiveness through design and productivity measures
? Reliability
? Modularity that helps for a fail-safe (degraded) operation in the event of failure of one module
? For Utility Management
? Surge protection saves Luminaires from damages
? Effective Operations & Maintenance Focus
? Wire less networking and communications
? Remote Monitoring / diagnosis / early repairs or replacements
? Less breakdowns
? Energy Audits
? Wi-fi Controls for conservation of power
? Energy Management
? Identification of pilferages
? Smart grid ready - IP enabled Smart grid based operation
? Sensors for weather reporting - temperature, wind, humidity etc
? Cameras for using the footages later for any surveillance purposes

The present invention discloses certain technological, ecological and managerial solutions incorporated in the design of Street / Outdoor lighting that have become relevant in the context of the Indian power conditions and the proposed futuristic 'smart grid compliance '.

The present invention brings out several models of luminaire designs to be configured for deployment in typical outdoor applications covering both protected and unprotected / open environments - one for the high end range (up to 200Watts equivalent to 400W conventional lights) and another, a miniaturised version, which goes into one's pocket, covering a very low end region of 12 to 30Watts (upto 70W conventional lights). In addition, a modular architecture is also proposed which enables multiple (1 to 3) light modules to be packaged together to realise intermediate wattages / light levels.

Meeting Indian conditions:
Besides the functional specifications of wattages and lux levels desired, the following features are incorporated to make the products smart and cost effective to perform efficiently in the environments and power conditions prevailing in India, particular in the rural parts of the country.

Wide Input voltage range: 90V to 305V
The luminaires can perform in a wide range of input voltage conditions with adequate margins for meeting typical low or over voltage situations that usually prevail in the Indian conditions particularly in rural areas. Custom packaged LED chips are employed to work with a safe margin over the operating range to tolerate very low / high voltages at the input.

Safety with Multi Level Surge Protection:
The street lights contain surge protection electronics at the luminaire level and at the pole level to take care of wide fluctuations in the input voltages and also accidental high voltage spikes. Surge protection equipment to protect the luminaire from high voltage surges, accidental 11KV transmission wire drops and improper earthings etc is provided not only in the luminaire but also in the field, at the rate of 1 unit for a row of multiple poles / lights i.e one-to-many as it is adequate and economical to take care of such power conditions prevailing in our country and it is not necessary to provide at the rate of one-to-one.

Cost effectiveness and Productivity Aspects:

? Housings – Low end (12-30W) :
? Bio-degradable thermo plastic material with IP ratings of IP 66 / 67 with less weight and efficient thermal management for lower wattages.

Housings – High end (up to 200W):

? Embedded thermo plastic exterior shield with any of the following:

? Aluminium die-casting and powder coated surface finish for IP ratings of IP 66 / 67 with optimized design for less weight and improved thermal management
? Extruded Aluminium plate like street light housing with steel surface finish for IP 66 / 67 with less weight, high productivity and efficient thermal management (of prior art 4197/CHE/2014)
? Modularity - Multiple modules (of 20 – 40W) of Bio-degradable thermo plastic material with IP ratings of IP 66 / 67 with less weight and efficient thermal management to be integrated into a single frame

? Modular architecture
? For LED PCBs and integral composite lens system for secondary optics
? Limited number of modules
? Easy to configure for any desired application / specification

? LED Drivers
? Operating on rectified AC rather than rectified and filtered DC Voltages
? Limited number of components, less cost, high reliability
? No magnetics

- Shock proof features during installation and maintenance
- Biodegradable material facilitates easy disposal

These lighting solutions are expected to greatly help the lighting infrastructure in India in terms of manufacturability, economy, safety, maintainability, automation, energy saving and eco-friendliness.

The present invention is described with the help of the Diagrams and Photographs contained in the next section.

The sub-systems that mainly contribute for the benefits expected from this invention are Housings, LEDs, LED driver/power supply units and the surge protection mechanism. While several networking and communication features of the prior art extend support for supervisory controls like Operations & Maintenance (O&M), certain additional components like sensors (temp, humidity etc) and webcams enable other value added services like weather reporting and recording visual snapshots for incident investigation to the Utility Managers.

Housings
The designs of the LED street lights of prior art employed die-cast aluminium housings with powder coated surface finish for suitable IP rating for outdoor applications for withstanding essentially temperatures and pressures caused by sun, dust, rain, humidity and wind. The LED light sources with lenses on each LED, are placed in enclosures covered with toughened glass with necessary beading / gaskets providing necessary leak proof arrangement. The top surface of the aluminium housing has been provided with a number of fins for radiation of the heat developed inside into the ambient.

The essential limitations of this design are: i) weight of the housing is significant which has a bearing on the ability of the pole to withstand - particularly in the case of replacement of conventional lights with LED lights ii) number of moulds were used for different power ratings of the luminaire (e.g. one for upto 30W and one for 30-120W etc) for production purposes which are expensive iii) Individual lenses are optionally provided to effect desired directivity of light onto the target area and iv) the toughened glass may not be able provide necessary leak proof compartment at times.

To overcome these limitations, certain attempts were made and reported in the prior art. These include an extruded sheet like luminaire housing provided with an enclosure wherein an integrally formed sheet of lenses is fitted tightly in close contact with the LED assembly on the MCPCB (Patent pending 4197/CHE/2014 dt 28.07.2014). The advantages are : simplified packaging with less number of components or subsystems, improved productivity and less cost to the end user.

In the present invention a novel housing design is proposed. The housings are essentially formed through thermoplastics material for use in both indoor and outdoor lighting applications. The formulation essentially contains lactic acid which has characteristics of biodegradability, correct thermal resistance and the mouldability property of being into rigid solid shape to accommodate PCB assembled with LEDs and other components.

One type of thermoplastic housing was discussed in prior art (Patent pending 849/KOL/2010) for use in conjunction with a bulb for indoor applications. The present invention is an improvement over that in several respects - the material formulation is different, thermal management is more effective due to better thermal characteristics, the former method used a number of fins for ventilation while the present method has a solid shape with fewer fins, the present material is unbreakable while the earlier model was fragile, the present material is biodegradable while the earlier model was not, the present material is light weight in comparison to the earlier model.

The Thermoplastic technology with its salient characteristics of light weight, effective thermal management / heat outflow by ventilation and low cost is explored for outdoor applications by providing suitable ingress protection like IP68. The thermoplastic body provides for low weight, less number of fins for efficient thermal management and eco-safe disposal in addition to all other performance capabilities.

In the proposed housing embodiment, the die cast aluminium or extruded plate aluminium housing is embedded in thermo plastic exterior. The housing comprises a thermoplastic layer over die-cast aluminium housing structure or the extruded plate type housing structure. The combined housing design facilitates higher productivity and efficient thermal management in ventilating the heat developed inside into the ambient to keep the LED junction temperatures within LED operational limits and ensure long life preferably 50000 hours for LED light sources.

The light supporting housing contains one or more LED PCB together with optical lenses which are forming an integrally formed sheet architecture. The LED PCBs with the integral optical lenses are assembled in said light supporting housing in modular manner for desired illumination. The LED PCBs are disposed in one side of the light supporting housing spaced apart from each other to integrate operational gap between two consecutive LED PCBs for dissipation of the heat form the LEDs while operating and reducing overall weight of the light supporting housing. The light supporting housing also comprises surface fins on the opposite side of the LED PCBs to facilitate the heat dissipation. The number of the LED PCBs in the light supporting housing is determined to get the desired illumination by involving the single light supporting housing.

High end – Embedded aluminium in thermo plastics:

In this embodiment, the housing (Figure ref 2) is directed to work for the range of 30- 200W. Pressure die-cast process is used to produce two or three types of light supporting housing housings (to accommodate no. of LED PCBs as desired - one, two or three), the job coming out of the mould can be accordingly selected. The housing as shown in fig 2 can have one, two or three provisions for assembling the LED PCBs with integral lens for secondary optics. The top view 101 shows that the surface is spread out with as many gaps and fins as possible to drive away the heat and hence the thermal issue is addressed for the higher wattages targeted. The LED PCBs are shown as 2X5 matrix 107, but they can be designed for any size to meet the specifications. The overall weight of the housing is also significantly reduced due to reduced overall dimensions as well as the no. of gaps built in. The production process is simple and hence higher productivity is achieved. After the housing is fabricated the only component to be assembled is the MCPCB with LEDs and the integral lens 108 over that. The Electronics including LED Driver / Power Supply and Embedded systems 109 are housed in the compartment next to the LED PCB section. Reduced weight of the luminaire housing helps in reducing the strain of the luminaire on the pole arm, hence the new luminaires can be safely fitted onto the existing old poles for replacements.

The invention makes use of the thermo plastic technology to improve the housing designs of the LED Luminaires by embedding the Die-cast aluminium or extruded plate type aluminium housings within a thermo plastic exterior to take advantage of the characteristics of light weight and effective thermal management of the thermo plastics.

Low end – thermo plastics:
In this embodiment, it is a miniaturised version ( Fig 3) with a compact, portable type of light which can be used for low end applications, between 12 to 30 Watts. The housing 202 is made of bio-degradable thermo plastic and of light weight, the surface is smooth and does not result in accidental cuts or injuries while handling. The top surface 201 is having large number of fins 203 for thermal management. The material comes in its native colour and hence no powder coating required for finish.
The light weight body with adjustable fixing clamp 208, can be easily retrofitted into the existing old brackets / pole arms of any size, without straining them with their weight. Transportation and installation also are easily carried out.

An earlier model of Thermo plastics technology is discussed in prior art (Patent pending - 849/KOL/2010) for use in conjunction with a bulb for indoor applications. In the present invention the housing for outdoor street light applications deploys an improved biodegradable thermo plastics technology with suitable IP ratings of 66 / 67.

Modular Architecture:
In this embodiment a thermoplastic module (Figure ref 4) is designed for 20-40 W and as many such modules as are required may be integrated in a single frame. The thermoplastic 302 body provides for low weight, number of fins 303 for efficient thermal management and safe disposal in addition to all other performance capabilities.

LEDs
Presently single white LEDs are used with wattages of 1-2W. The LED technology is offering superior lumen per watt light output and the packaging technology is allowing for more number of LEDs to be accommodated in a single package enabling higher wattage devices and in turn, higher wattage luminaires to be realised within the space available in the housing. This custom integrated LED packaging facility is deployed in the present invention whereby the chip cost is significantly reduced and the economies in production can be translated into more lumens per rupee or dollar.

LED Drivers
A proprietary technology has been (Patent pending - 6202/CHE/2013 ) used to utilise rectified AC in place of rectified & filtered DC power supplies for use in LED bulbs. The same technology is extended to realize higher wattage street light luminaires also. The higher wattage requirements for street lights are met with multiple LED segments and rectified AC drivers - in the form of multiple bulbs configuration. The rectified AC operation results in elimination of magnetic in the filter circuits, which implies inductors and capacitors, hence reduced number of components, thereby increased reliability and reduction in component costs.

Surge Protection Mechanism
The street lights are equipped with surge protection electronics at the luminaire level and also at the field level to take care of wide fluctuations in the input voltages and also accidental high voltage spikes. In addition, surge protection equipment to protect the luminaire from high voltage surges, accidental 11KV transmission wire drops, improper earthings etc is provided in the field at the rate of 1 unit for a row of multiple lights. It is not necessary to provide one-to-one (per pole) and one-to-many (per many poles) is adequate and economical to take care of such power conditions prevailing in our country.

Reference is next invited from the accompanying figures 4 and 5 which show the external and internal schematic illustration of the present Centralised Control & Monitoring Systems (CCMS) for Smart Grid Applications. The present CCMS is adapted to be used in street lighting applications and primarily meant for any one or more from 1) Energy Savings, 2) Energy Optimisation, 3) Health Monitoring of the Street Lights for repair and replacement purposes, 4) Tracking of Electrical Parameters for the safety of the lighting devices and 5) Alerting the concerned authorities in the event of any abnormal developments in the line conditions.

CCMS facilitates automatic on/off functions to ensure switching-on and switch-off functions of the street lighting system based on either ambient conditions or scheduled time frames. The system can also effect automatic dimming in a programmed way at prescribed times or in a prescribed profile. These functions are aimed at ensuring energy savings and energy optimization. CCMS will also capture all the metering data from the consumer points.

The system is adapted to monitor the functioning of each individual street light and diagnose the device condition enabling the maintenance agency to take quick corrective action. The system is also adapted to monitor the electrical parameters associated with the street lighting system to get warned well in time for situations warranting preventive and corrective measures.
CCMS is designed for reporting the observations to multiple recipients as per stipulations. Targeted recipients, in respect of street lighting complexes, can be municipal authorities, supplier of the lighting systems, maintenance agency, the concerned DISCOM and relevant regulatory authorities.

The CCMS is contemplated in all street lighting solutions as a basic and captive in-built feature. The same can also be adopted for the emerging smart grid applications in the street lighting projects.

Conclusion

The bio-degradable thermo plastics technology is explored to reduce the weight of the luminaires at the same time improving the thermal conductivity to take away the heat developed within the housing into the environment. The Aluminium die-cast model or the extruded plate type of housings with limitations on the higher wattage applications are suitably embedded into the thermo plastics with reduced sizes of the metal.

LED street lights are vital components in the demand side management of the power sector. They provide energy efficient lighting solutions for outdoors in both urban or rural environments. Grid based lighting solutions with energy efficiency features are sought after to save grid power as it implies that the power saved is equivalent to twice the power generated. It is also expected to help to bridge the demand supply gap between power generation and utilisation. There is a thrust on energy savings by municipalities and local bodies. In order to implement an energy management system to this effect, power distribution agencies are contemplating state-of-art technology solutions to streamline right and proper utilisation of power and at the same time, eliminate inefficient and improper use of electricity. This is being manifested through what is termed as smart grid application.

LED Lights are characterised by high initial cost, but the sizable savings realisable through reduced power consumption, very long life, minimal or no maintenance / replacement expenditure for about as many as 8 years after installation – are tempting the municipalities and local bodies to seriously consider proposals for change over to LED lights. Energy Saving Companies (ESCO) are envisaging to take up these projects for initial funding and recovery over several years with assured returns from the energy savings. The Energy distribution companies are relieved of the operational and maintenance activity and are shifting their focus onto energy management. To this effect, they are deploying state-of-art techniques and tools called ‘Smart Grid environment’. It is now the task for the LED Street Light vendors to make their products more efficient and feature rich to function in such an environment and demonstrate their worth.

The present invention seeks to augment the design / manufacture of LED street lights with features to enable them graduate to a 'smart-grid-ready' status for deployment in those applications or environments, specifically to operate in the Indian power situations. These lighting solutions are expected to greatly help the lighting infrastructure in India in terms of manufacturability, economy, safety, maintainability, automation, energy saving and eco-friendliness.
,CLAIMS:WE CLAIM:

1. A light emitting diode (LED) based lighting fixture for outdoor applications comprising

a light supporting housing for containing one or more LED PCB together with optical lenses forming an integrally formed sheet architecture;

The said supporting housing being a thermo plastic housing of the LED Luminaires by embedding the Die-cast aluminium or extruded plate type aluminium housings within a thermo plastic exterior to take advantage of the characteristics of light weight and effective thermal management of the thermo plastics

said LED PCBs with the integral optical lenses are assembled in said light supporting housing in modular manner for variable illumination and disposed in one side of the light supporting housing spaced apart from each other with operational gap between two consecutive LED PCBs favouring dissipation of the heat form the LEDs while operating involving integral solid shaped light weighted heat dissipating light supporting housing.

2. The LED based lighting fixture for outdoor applications as claimed in claim 1, wherein the light supporting housing comprises surface fins on the opposite side of the LED PCBs to facilitate the heat dissipation.

3. The LED based lighting fixture for outdoor applications as claimed in anyone of the claim 1 or 2, wherein electronics including LED driver /power supply and embedded systems are housed in a compartment in the housing next to the LED PCB section.

4. The LED based lighting fixture for outdoor applications as claimed in anyone of claims 1 to 3, wherein number of the said LED PCBs in the light supporting housing is determined to get the desired illumination by involving the single light supporting housing.

5. The LED based lighting fixture for outdoor applications as claimed in anyone of claims 1 to 4, wherein the housing is essentially formed by involving thermo plastics for use in lighting applications, to improve the housing designs of the LED Luminaires by embedding the Die-cast aluminium or extruded plate type aluminium housings within a thermo plastic exterior to take advantage of the characteristics of light weight and effective thermal management of the thermo plastics.

6. The LED based lighting fixture for outdoor applications as claimed in anyone of claims 1 to 5, wherein the housings comprises a thermoplastic layer over die-cast aluminium housings or the extruded plate type housing structure for facilitating higher productivity and thermal management in ventilating the heat developed inside into the ambient to keep the LED junction temperatures within LED operational limits and ensure long life preferably 50000 hours for LED light sources.

7. The LED based lighting fixture for outdoor applications as claimed in anyone of claims 1 to 6, wherein housings thermoplastic formulation essentially contains lactic acid having characteristics of biodegradability, proper thermal resistance and mouldablility into rigid solid shape to accommodate the LED PCB assembled with other components.

8. The LED based lighting fixture for outdoor applications as claimed in anyone of claims 1 to 7, wherein the housing is light weighted and comprises adjustable fixing clamp for easily retrofitting in any existing bracket/ pole arms of any size without straining them with weight.

9. The LED based lighting fixture for outdoor applications as claimed in anyone of claims 1 to 8, comprises a centralized Control & Monitoring systems for using in street lighting applications and facilitating one or more from (i) energy savings, (ii) energy optimization, (iii) health monitoring of the street lights for repair and replacement purposes, (iv) tracking of electrical parameters for safety of the LEDs and (v) alerting concerned recipients in event of any abnormal developments in line conditions.

10. The LED based lighting fixture for outdoor applications as claimed in anyone of claims 1 to 9, wherein the CCMS facilitates automatic on/off functions to ensure switching-on and switch-off functions of the street lighting system based on either ambient conditions or scheduled time frames and also enabling automatic dimming in a programmed way at prescribed times or in a prescribed profile to ensure energy savings and energy optimization.