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SOLAR POWER SATELLITES
INTRODUCTION
What is SPS ?
Importance of SPS
Difference between gen.satellites & SPS
Background of SPS
Recent NASA efforts
 Fresh look study
SSP concept definition study
SSP exploratory and research technology program
a) System study and analysis
b) SPS research and analysis
c) SPS technology demonstration
General idea of SPS
Location & Constructional features:
a) Geo stationanary orbit
b) SPS are massive .length=10.5km
c) Width=5.3km
d) Avg. area=56 sq.kms, weight=500tons
e) Surface consists of 400 billion solar cells
f) Diameter of transmitting antenna=10km
g) Diameter of receiving antenne=1km
Why SPS should be large?
 Due to the principe of power beaming
What is the principle power beaming?
 Smaller the transmitter array larger the angle of deviation
 High divergent beam covers a large area
Methods to improve the overall efficeincy of WPT system
 The overall efficiency of the WPT system can be improved by
 • Increasing directivity of the antenna array
 • Using dc to ac inverters with higher conversion efficiency
• Using schottky diode with higher ratings
MICROWAVE POWER TRANSMISSION IN SPS
 The microwave transmission system as envisioned by NASA and
 DOE would have had three aspects [5]:
 1. The conversion of direct power from the photovoltaic cells, to
 microwave power on the satellites on geosynchronous orbit above the
 Earth.
 2. The formation and control of microwave beam aimed precisely at fixed
 locations on the Earths surface.
 3. The collection of the microwave energy and its conversion into electrical
 energy at the earth’s surface.