This question appears in Mumbai University > Satellite Communication and Network subject

Marks: 5 M

Year: May 2015

The function of the electrical power system of the satellite is to deliver DC power to all the components of the satellite. For this purpose it contains solar cells and standby batteries.

Solar cells –

• The satellite uses solar cells to generate DC power. The solar panels are used which are arrays of the solar cells connected in series and parallel circuits. The solar panels produce about kilowatts of power to provide it to the subsystems of the satellite.
• The amount of power generated by the solar panels depends on the conversion efficiency of the cell and the intensity of the incident solar radiation on the solar panels.
• The efficiency of the solar panels depends inversely on the temperature of the components and also on the aging and damage caused to the components.
• Also the solar panels are bombarded by particles such as electrons and protons. Therefore the cells are protected by material like fused silica.

Standby batteries –

• A geostationary satellite undergoes eclipse during which it uses standby batteries as it do not get solar power from sun during eclipse.
• The batteries are allowed to discharge till the depth of 0.7 to 0.9 of the full charge.
• The batteries are recharged when the satellite moves out of the eclipse.
• The operation status of the batteries is controlled by the ground commands.

The DC power from the solar panels is conditioned to provide high DC voltage to some components of the satellite like TWT.

Electrical Power Sub-System