WIRELESS POWER TRANSMISSION FOR SOLAR POWER SATELLITE. OUT LINE. 1.Executive Summary. 2.SPS System. 3.Recent Technologies and research Antenna and Transmitters- Beam Control, Target Detection, Propagation Receivers and Rectifiers 4.Efficiency.
WIRELESS POWER TRANSMISSION FOR SOLAR POWER SATELLITE
3.Recent Technologies and research
Antenna and Transmitters-
Beam Control, Target Detection, Propagation
Receivers and Rectifiers
5.Radio Science Influences and Effect of SPS.
- Communication System.
- WPT System.
Typical WPT is point – point power transmission.
Famous taper method.
suppression of side lobe
To increase the power transmission efficiency.
Area of Significant Concern
Area of Significant Benefit
SOLAR POWER SATELLITE SYSTEM
It consists of mainly three segment.
1. Solar energy collector
2. DC to Microwave converter
3. Large Antenna Array.
RECENT TECHNOLOGIES AND RESEARCHES
1. ANTENNAS AND TRANSMITTER
Antennas for Microwave Power Transmission
All antennas can be applied for both the MPT system and communication system
We have to use a phased array antenna for the MPT from/to moving Transmitter/receiver.
Recent Technologies for Transmitters
Generation of Microwave
Need higher efficient generator/amplifier.
Highly efficient beam collection on rectenna array.
Higher stabilized and accurate phase and
Amplitude of microwave when we use phased
array system for the MPT.
Microwave Generator/Amplifier option for MPT
1.Microwave Tube (Cooker-type Magnetron)
Generate and amplify high power microwave (over kW) with a high voltage (over kV) imposed.
Unstable freq/Uncontrollable phase.
It generate low power micro wave with a low voltage
It is easy to control a phase and amplitude
Especially F class amplifier is expected as high efficient amplifier for the MPT system.
Distinguished from the ordinary use of the microwave technology
Pureness in spectrum
Efficient power generation and high efficient detector in a small and light fashion
Precise beam control
Compare the weight by power-weight ratio.
2.BEAM CONTROL, TARGET DETECTION, PROPAGATION
Recent Technologies of Retro directive Beam Control
2.Van Atta Array
3.Phase conjugate Ckt.
VAN ATTA ARRAY
PHASE CONJUGATE CIRCUIT
There are another method for the target detection is “Software Retro directive”.
Computer is usually used for the software retro directive.
3. RECEIVERS AND RECTIFIERS
Cyclotron Wave Converter
1.RF-DC Conversion Efficiency.
2.Beam Collection Efficiency.
3.DC-RF Conversion Efficiency.
1. RF-DC Conversion Efficiency.
Efficiency of Rectenna – 80%
Decline of the Efficiency is caused by
-Array connection loss
-Change of connected load
-Trouble of the rectenna
-Any losses on the system(DC/AC conversion, cable)
(a) Efficiency of 2.4 GHz Rectenna
(a) Efficiency of 5.8 GHz Rectenna
2. Beam collection Efficiency
Beam collection efficiency depends .
- transmitter and receiver aperture areas.
- wavelength, and the separation distance between
the two antennas
Efficiency – 89%
Decline Efficiency caused by
-Amplitude Error on a Phase Array.
The rise of the side lobe decreases antenna gain and beam collection efficiency.
3. DC-RF conversion Efficiency.
We do not have to steer a micro-wave beam electrically.
If we need to steer (Guide or control).
We use phase shifter without grating lobes.
Power loss of the phase shifter is 4-6dB. - To solve this problem we use low power amplifier after high loss phase shifter without grating lobes.