Claims:We claim
1. A solar tractor (18) with an array of solar panels (1) mounted horizontally on the roof of the tractor in such a way that sun rays (20) fall directly fall on the solar panels (1) generating DC current which is fed to the controller (13) which further transfers the current to the tractor motor (15) to run and operate the tractor motor (15) and agricultural implements.
2. Apparatus of claim 1 further comprising where the surplus current is transferred by the Controller to be stored in rechargeable batteries (14).
3. Apparatus of claim 1 further comprising where in the absence of sun rays, current is transferred from stored rechargeable batteries (14) through the controller (13) to the tractor motor (15).
4. Apparatus of claim 1 and 3 further comprising where, when there is deficit current from the PV Panels (1), necessary current is drawn from rechargeable batteries (14) through the controller (13).
5. Apparatus of claim 1 and 3 where current is drawn from stored rechargeable batteries (14) trough the controller (13) to an inverter (16) to run external appliances. , Description:TITLE: - SOLAR TRACTOR

Field of the Invention and use of Invention:-

This invention relates to a Solar Powered Electric Tractor.
ADVANTAGES OF AN SOLAR POWERED ELECTRIC TRACTOR.
1. Better lower end torque, i.e. power.
2. Better delivery of power to the ground and steering control.
3. Lower center of gravity.
4. No fossil fuels required, safer, less harmful to the environment.
5. Less heat, Less noise, less vibration, less moving parts, less maintenance, less offensive smells.
6. Lower cost of maintenance, easier to service, modular subsystems.
7. Electric motors commonly used for powering heavy equipment so maintenance and repair widely available.
8. Free low cost power from the sun, after the cost of the Photo Voltaic “solar cells” and batteries and charge controller are recouped.
9. Tractor batteries can be changed out in a few minutes.
10. Electric Tractor has increased area on board for implements. Three conventional 3-point implements can be operational at the same time.
11. 3-point attachment systems operated with electric servo motors increasing functionality and ease of use. i.e. can lift and adjust bottom two mounting points independently, great for adjusting attachment angle as well as height. Manual adjustments no longer required.
12. Multiple functionality of charging system equipment. Can be used to charge Tractor and or to power the entire home instead.
13. The solar power charging system is same as solar home systems, making parts, installation, and maintenance less expensive and readily available.
14. Power produced for Tractor is available to power devices on the farm anytime or to power the home if grid power is down.
15. Personal solar charging system costs can be delayed. The Tractor can be charged from grid power at a cost savings over petroleum based fueled Tractors. Grid power is a little more efficient producer of power than petroleum based engines when including transportation costs, etc.
16. Weight of batteries is an advantage in Tractors as it increases useful traction. Operational efficiency increased.

The weight of the Tractor is approximately 600 kg. The gear ratio is 4+1. Due to the small size of the Tractor it can be efficiently used to cultivate in small area it can cultivate about 1 (one) acre per hour at a speed of 15 to 20 km per hour. It is very useful for horticulture (Bagayat farming)

Prior Art and problem to be solved

The world is clearly running out of oil and gas, yet most people ignore the coming crisis. Food production and distribution in the industrialized world have become so dependent on petroleum uses, that it's hard to imagine how agriculture will function without this fuel.

Farming Tractors where since the dawn of the human civilization, there have been efforts of humanity to master the land and its utilization regarding the farming and generally the food production. It is widely known that the introduction of the first farming Tractors altered the farming activities and food production as nothing else did before. The dramatic increase of the global population that occurred at the end of the 19th century is partly related to the industrialization of agriculture (farm mechanization). The core of the industrialization of farming is the farming Tractors; they maximized the efficiency of the farming activities by removing human and animal labor from the field, thus minimizing the ratio human labor/land area. Apart from the ease that farm mechanization offered to humanity, it is the cause of connecting the food production with the energy demands.

The most promising option is solar-powered electric Tractors, which offers several advantages over gas diesel-powered Tractors. Electric motors can operate at more than 90 percent efficiency, while combustion engines are less than 15 percent efficient. Electric propulsion is ideally suited to high torque, slow-speed agricultural operations. Electric motors have only one moving part and require little maintenance. Internal combustion engines, on the other hand, have hundreds of moving parts and require a lot of maintenance.

Electric motors don't idle, which saves energy. Plus, while the vehicle is going downhill or braking, an electric motor can become a generator and return energy to the battery. This process, called regenerative braking, further increases the efficiency of electric propulsion and cannot be duplicated using other technologies. Electric-wheel motors eliminate the need for an internal combustion engine, transmission and differential allowing new options in the design of Tractors. Mounting an electric motor in the hub creates a self-propelled wheel that can provide new levels of versatility and visibility.
If an electric Tractor is combined with photovoltaic (PV) charging, whether on the Tractor itself in the form of a solar panel shade canopy or on the roof of a building, no other fuel source is necessary. Unbreakable PV panels and PV roofing that can turn any sunny surface into a power station. Photovoltaic’s provide an ideal energy source for agriculture because the growing season coincides with the availability of solar energy.

Known Solar powered Tractors transfer current generated from PV panels to rechargeable batteries, which in turn provide current to the Tractor motor. Our invention directly transfers current from PV cells to the Controller, which in turn transfer the current to the Tractor Motor (15). Surplus current is stored in the rechargeable battery (14). When needed deficit current is drawn from the power stored in the rechargeable batteries (14).

Objects of the Invention

It has already been proposed a solar operated Tractor

The principal object of this invention is to reduce dependence on fossil fuels, and be safer and less harmful to the environment.
Another object of this invention is to efficiently cultivate small farms.
A further object of this invention is to in the time of grid failure to power entire home.
Another object of this invention is to have better power.
A further object of this invention is to delivery better power to the ground and better steering control.
A further object of this invention is to reduce the gross weight of the Tractor.
Another object of this invention is to lower maintenance cost and easier to service.
A further object of this invention is to generate less heat, less noise, less vibration, less moving parts, less maintenance, less offensive smells, less pollution.
Another object of this invention is to increase the space available on the Tractor for agricultural implements.

Summary of the Invention

In The last century the earth experienced a huge booming of its population. The rate of this growth has been the biggest ever and all major predictions estimate that it will continue. Goods are becoming more and more valuable. After the huge industrial revolution, the next huge step from mankind was to invent new ways of transforming the energy from the sun, into useful energy for all kinds of activities. Practically, the sun will not expire before the end of earth’s life, this fact drives to the assumption that these types of energy sources are considered renewable. Apart from energy, another major good that is fundamental for all societies is food. Agriculture is the science that circulates all activities related to food production. It seems that the future of both goods will find them bonded and especially food production will be directly dependable to the energy. Adding to this, the demand for food production industry will increase and require more energy; hence it will add to the environmental depletion, by releasing CO2 to the atmosphere.

Farming Tractors where since the dawn of the human civilization, there have been efforts of humanity to master the land and its utilization regarding the farming and generally the food production. It is widely known that the introduction of the first farming Tractors altered the farming activities and food production as nothing else did before. The dramatic increase of the global population that occurred at the end of the 19th century is partly related to the industrialization of agriculture (farm mechanization). The core of the industrialization of farming is the farming Tractors; they maximized the efficiency of the farming activities by removing human and animal labor from the field, thus minimizing the ratio human labor/land area. Apart from the ease that farm mechanization offered to humanity, it is the cause of connecting the food production with the energy demands.

Solar photovoltaic panels are one of the major and oldest main role players in electricity generation and they are being developed for over a half century, they generate DC electrical power from the sunlight. The main obstacle with the solar energy is that it is available only during daytime hours, thus to match the demand needs during the 24 hours, the energy must be stored. In order to increase the usage of generated solar energy, which is non-despatchable, energy storage devices are necessary. Batteries are the most widely used energy storage devices. Batteries are storing electrical energy by transforming it into chemical and vice versa when they are releasing it. Batteries and solar panels share a very crucial attribute and that is the DC current of the electrical power.

Our invention relates to a solar powered electric Tractor. The solar energy is captured from the rooftop solar PV panels mounted on the roof of the solar Tractor. The energy is stored directly from the PV panels to the batteries. This energy is used to power the motor for running the Tractor and agricultural implements.

ADVANTAGES OF OUR INVENTION OVER CONVENTIONAL TRACTORS.
17. Better lower end torque, i.e. power.
18. Better delivery of power to the ground and steering control.
19. Lower center of gravity.
20. No fossil fuels required, safer, less harmful to the environment.
21. Less heat, Less noise, less vibration, less moving parts, less maintenance, less offensive smells.
22. Lower cost of maintenance, easier to service, modular subsystems.
23. Electric motors commonly used for powering heavy equipment so maintenance and repair widely available.
24. Free low cost power from the sun, after the cost of the Photo Voltaic “solar cells” and batteries and charge controller are recouped.
25. Tractor batteries can be changed out in a few minutes.
26. Electric Tractor has increased area on board space for implements. Three conventional 3-point implements can be operational at the same time.
27. 3-point attachment systems operated with electric servo motors increasing functionality and ease of use i.e. can lift and adjust bottom two mounting points independently, great for adjusting attachment angle as well as height. Manual adjustments no longer required.
28. Multiple functionality of charging system equipment. Can be used to charge Tractor and or to power the entire home instead.
29. The solar power charging system is same as solar home systems, making parts, installation, and maintenance less expensive and readily available.
30. Power produced for Tractor is available to power devices on the farm anytime or to power the home if grid power is down.
31. There are many efforts being made to move people to solar based systems; home based solar systems, other countries moving to replace grid power from sun power.
32. Personal solar charging system costs can be delayed. The Tractor can be charged from grid power at a cost savings over petroleum based fueled Tractors. Grid power is a little more efficient producer of power than petroleum based engines when including transportation costs, etc.
33. Weight of batteries is an advantage in Tractors as it increases useful traction. Operation is efficiently increased.

The weight of our Tractor is approximately 600 kg. The gear ratio is 4+1. Due to the small size of the Tractor it can be efficiently used to cultivate in small area it can cultivate about 1 (one) acre per hour at a speed of 15 to 20 km per hour. It is very useful for horticulture (Bagayat farming).

Detailed Description of the Invention

As shown in Figure {1} solar rays (20) from the sun fall on an array of PV Cells. Solar panels (1) are mounted horizontally on the roof top of the Tractor. The PV Cells (1) are mounted such that it covers the entire roof of the Tractor. Solar photovoltaic cell [PV cell] (1) which converts visible light into direct current (DC). This DC Current is fed to the controller (13). The controller then transfers the DC Current to the Tractor motor (15). If the Tractor motor (15) does not require the supplied current or surplus current is generated, then, surplus current would be transferred by controller (13) to the rechargeable battery (14).

As shown in figure {3} During normal operations at the time of running the Tractor and using the agriculture implements for operating different agricultural operations, the controller would transfer all the energy received as DC Current from the PV cells (1) to the Tractor motor (15). If the transferred current or current received by the Tractor motor (15) is not sufficient to do the different operations connected with the Tractor motor (15) then deficit power would be drawn from the rechargeable battery (14).

Figure {2}: - In situations when the weather is cloudy or Tractor operations are to be done in the evening or night, i.e. when sun rays are not enough to generate electricity through the PV panels to run the Tractor motor (15) for doing all necessary functions. In such a situation as shown in figure {2}, rechargeable battery (14) would be supplying power to Tractor (15) through the controller (13). Thus, normal operations of the Tractor can also be achieved in the absence of sunrays (20).

Figure {4}:- Our solar Tractor can also be used to supply power to home appliances. As shown in figure {4}, solar rays (20) would be captured by PV panels (1) converted into DC Current. Controller (13) will divert the current to the batteries (14) which in turn would be supplied to the input of the inverter whose output would be connected to the input of residential domestic power (17) to run different home appliances or instruments.

The controller is the primary part which controls the manner in which the power received from the PV panels is to be distributed amongst the rechargeable battery (14) or the Tractor motor (15).

Figure {5}: - Describes the distribution of power when solar energy is available and the Tractor has to be fully operational to complete the different functions. Solar Panels (1) directly feed the power to the controller (13) which in turn transfers the required power to the Tractor motor (15). A situation may arise when the Tractor is stationary or not active, here the Tractor motor (15) would not require any power input, the controller (13) would transfer the power to the rechargeable battery (14).

Figure {6}: - Describes distributions of power when solar energy is not available and the Tractor has to be fully operational to run the different tasks. Energy is supplied to the Tractor motor (15) by the rechargeable battery (14) through the controller (13).

Figure {7}: - Describes distributions of power when solar energy is not available and the Tractor has to be fully operational to run the different tasks. The energy provided from the output of the PV Panels (1) is not enough to fully run the Tractor motor (15) deficit energy is supplied to the Tractor motor (15) by the rechargeable battery (14) through the controller (13).

Figure {8}: - Shows the top view of the Tractor. The PV Panels are horizontally mounted on the top of the Tractor in such a way that they cover the entire body of the Tractor.

Figure {9}: - Shows the left hand side view of the Tractor.

Figure {10}: - Shows the right hand side view of the Tractor.

Figure {11}: - Shows the front view of the Tractor.

Tractor parts such as Solar panel (1), Front Wheel (2), Rear wheel (3), Tractor Bonnet (4), PV panel support Rod (5), Front wheel Axel (7), Rear Wheel Axel (8) and Rear Rod (11) for attaching agricultural implements and cover (12), are shown in figure {9}, {10} and {11}.