24-01-2013, 04:45 PM
BEAMED POWER TRANSMISSION FROM SOLAR POWER SATELLITES
[attachment=48358]
INTRODUCTION
The desire of the modern man for more and more amenities and sophistication led to the unscrupulous exploitation of natural treasure. Though nature has provided abundant source of resources. It is not unlimited. Hence the exhaustion of the natural resources is eminent. The only exception to this is sunlight.
Scientist who had understood the naked truth had thought of exploiting the solar energy and started experimenting in this direction even from 1970. But the progress was very slow. Much headway is yet to be made in this direction. However as the impotents source of non-conventional energy and due to the limited source of conventional energy emphasis has given for the better utilization of solar energy.
But the application of solar cell, photovoltaic cell etc, we are able to concert only a small percentage of solar energy into electrical energy. But by using beamed power transmission from solar power satellite we can envisage a higher percentage of conversion. By beamed power transmission, we can extend the present system of two dimensional transmission network to three dimensional, if does not have any environmental problem as well.
SOLAR POWER SATELLITE
The solar power satellite concept would place solar power plants in an above the earth where they could convert sunlight to electricity and beam the ground based receiving station. The satellite would be placed in sow called geostationary or earth synchronous orbit. 24 hour orbit that is thus synchronous with earth rotation. so the satellite placed their will stay stationary overhead from earths receiving antenna
The solar power satellite will consist of a large number of solar cells mounted on a frame of steel reinforced lunarcrete. the solar cell produces electricity from sun with no moving part. the only moving part of the satellite is the transmitter antenna, which slowly tracks the ground based rectenna while solar array keeps facing the sun. each transmitter antenna is connected to solar array by two sotary joints with slip rings.
Because solar panels generate low voltage dc, super conducting transmission line is used for transmission to microwave beamer instead of conventional copper conductors. operating super conducting transmission line at low voltage reduces the chance of voltage breakdown.
The vision is to generate a large Solar Power Satellite (SPS) system for space applications. In contrast to classical designs of solar power stations, the solar energy collected by the SPS system will not be beamed to the Earth's surface, but used to provide for the required electrical and/or propulsive power for vehicles in Earth orbit (LEO, MEO and GEO) and/or deep space vehicles. Transmission of the energy to these space vehicles is foreseen thought either beamed microwave or laser power at a power level that can substantially rise above todays power levels up to e.g. 20-50 kW per space vehicle (e.g. for a
telecommunications satellite in GEO). This power is received by a relatively low mass microwave or laser collection and rectifying system on board of the satellite.
Solar Power in Space
Although solar energy is abundant in the inner solar system, collecting enough of it to provide electricity for a large population of humans is a non-trivial matter. The most comprehensive studies of large-scale solar power generation in space were conducted over two decades ago. Legend has it that the concept of Solar Power Satellites was first envisioned by Dr. Peter Glaser as he sat in an early-1970's gas line. At the time there was an Arab oil
embargo, an energy crisis, and global concern about increasing use and decreasing availability of energy. People sometimes waited hours in lines at the few stations that had not run out of gas, sitting in cars that got 15 miles per gallon and had a range around 200 miles. There was plenty of time to think.
The idea of using solar cells to generate electricity in space was nothing new. Communications satellites had been doing that for years. Indeed, the most distinguishing characteristics of most Earth-orbiting satellites, even today, are their arrangements of solar cells. A common configuration is a cylindrical shape with the entire exterior covered in purplish-blue solar cells. Non-cylindrical satellites have large "wings" covered with solar panels. The crewed laboratories Skylab, Mir, and International Space Station all had or have large solar cell arrays that generate power for the satellites' use.
TRANSMITTING ANTENNA
The transmitting antennas are large active electronically steerable phased array. These arrays are composed of radiation module that consists of a high gain phased locked magnetron and directional amplifier that supplies microwave power to slotted waveguide array.
The antenna must have the ability to match the transmission line (source impedance) and load (atmosphere 377). If impedance match is correct, the energy being transferred will be radiated into the atmosphere.
An antenna is used to convert high frequency current into electromagnetic waves. It must have the ability to transfer energy alternatively from electrostatic to electromagnetic.
A co axial cable is used to connect the microwave source to a waveguide adaptor. The adaptor is connected to a ferrite circulator, which protects the microwave source from reflected power.
A phase shifter is used to produce a difference in shift between the radiation modules. Even though total difference in shift between radiation modules may be great, only a low power level phase shifter of 360o is needed in each module. Phase reference at each module is adjusted to some integral multiple of 360o relative to the source of reference.
The slotted waveguide antenna consists of 8 waveguide section with 8 slots on each section. These 64 slots radiate power uniformly through space to antenna in ground.
FREE SPACE TRANSMISSION
There is no economic burden for the transmission through space. The transmitting and receiving apertures are needed for transmission. The size and expense of this aperture has a direct relationship with the wave length that is being used, the distance over which energy is being sent and the desired efficiency of transmission.
[attachment=48358]
INTRODUCTION
The desire of the modern man for more and more amenities and sophistication led to the unscrupulous exploitation of natural treasure. Though nature has provided abundant source of resources. It is not unlimited. Hence the exhaustion of the natural resources is eminent. The only exception to this is sunlight.
Scientist who had understood the naked truth had thought of exploiting the solar energy and started experimenting in this direction even from 1970. But the progress was very slow. Much headway is yet to be made in this direction. However as the impotents source of non-conventional energy and due to the limited source of conventional energy emphasis has given for the better utilization of solar energy.
But the application of solar cell, photovoltaic cell etc, we are able to concert only a small percentage of solar energy into electrical energy. But by using beamed power transmission from solar power satellite we can envisage a higher percentage of conversion. By beamed power transmission, we can extend the present system of two dimensional transmission network to three dimensional, if does not have any environmental problem as well.
SOLAR POWER SATELLITE
The solar power satellite concept would place solar power plants in an above the earth where they could convert sunlight to electricity and beam the ground based receiving station. The satellite would be placed in sow called geostationary or earth synchronous orbit. 24 hour orbit that is thus synchronous with earth rotation. so the satellite placed their will stay stationary overhead from earths receiving antenna
The solar power satellite will consist of a large number of solar cells mounted on a frame of steel reinforced lunarcrete. the solar cell produces electricity from sun with no moving part. the only moving part of the satellite is the transmitter antenna, which slowly tracks the ground based rectenna while solar array keeps facing the sun. each transmitter antenna is connected to solar array by two sotary joints with slip rings.
Because solar panels generate low voltage dc, super conducting transmission line is used for transmission to microwave beamer instead of conventional copper conductors. operating super conducting transmission line at low voltage reduces the chance of voltage breakdown.
The vision is to generate a large Solar Power Satellite (SPS) system for space applications. In contrast to classical designs of solar power stations, the solar energy collected by the SPS system will not be beamed to the Earth's surface, but used to provide for the required electrical and/or propulsive power for vehicles in Earth orbit (LEO, MEO and GEO) and/or deep space vehicles. Transmission of the energy to these space vehicles is foreseen thought either beamed microwave or laser power at a power level that can substantially rise above todays power levels up to e.g. 20-50 kW per space vehicle (e.g. for a
telecommunications satellite in GEO). This power is received by a relatively low mass microwave or laser collection and rectifying system on board of the satellite.
Solar Power in Space
Although solar energy is abundant in the inner solar system, collecting enough of it to provide electricity for a large population of humans is a non-trivial matter. The most comprehensive studies of large-scale solar power generation in space were conducted over two decades ago. Legend has it that the concept of Solar Power Satellites was first envisioned by Dr. Peter Glaser as he sat in an early-1970's gas line. At the time there was an Arab oil
embargo, an energy crisis, and global concern about increasing use and decreasing availability of energy. People sometimes waited hours in lines at the few stations that had not run out of gas, sitting in cars that got 15 miles per gallon and had a range around 200 miles. There was plenty of time to think.
The idea of using solar cells to generate electricity in space was nothing new. Communications satellites had been doing that for years. Indeed, the most distinguishing characteristics of most Earth-orbiting satellites, even today, are their arrangements of solar cells. A common configuration is a cylindrical shape with the entire exterior covered in purplish-blue solar cells. Non-cylindrical satellites have large "wings" covered with solar panels. The crewed laboratories Skylab, Mir, and International Space Station all had or have large solar cell arrays that generate power for the satellites' use.
TRANSMITTING ANTENNA
The transmitting antennas are large active electronically steerable phased array. These arrays are composed of radiation module that consists of a high gain phased locked magnetron and directional amplifier that supplies microwave power to slotted waveguide array.
The antenna must have the ability to match the transmission line (source impedance) and load (atmosphere 377). If impedance match is correct, the energy being transferred will be radiated into the atmosphere.
An antenna is used to convert high frequency current into electromagnetic waves. It must have the ability to transfer energy alternatively from electrostatic to electromagnetic.
A co axial cable is used to connect the microwave source to a waveguide adaptor. The adaptor is connected to a ferrite circulator, which protects the microwave source from reflected power.
A phase shifter is used to produce a difference in shift between the radiation modules. Even though total difference in shift between radiation modules may be great, only a low power level phase shifter of 360o is needed in each module. Phase reference at each module is adjusted to some integral multiple of 360o relative to the source of reference.
The slotted waveguide antenna consists of 8 waveguide section with 8 slots on each section. These 64 slots radiate power uniformly through space to antenna in ground.
FREE SPACE TRANSMISSION
There is no economic burden for the transmission through space. The transmitting and receiving apertures are needed for transmission. The size and expense of this aperture has a direct relationship with the wave length that is being used, the distance over which energy is being sent and the desired efficiency of transmission.