The Indian Space Research Organisation (ISRO) is gearing up to demonstrate the use of an indigenously built electric propulsion system on a satellite later this year.
The system, featuring a 300 millinewton (mN) thruster, will be demonstrated on board a Technology Demonstration Satellite (TDS-01) that is expected to be launched in the second half of 2024, V. Narayanan, Director of Liquid Propulsion Systems Centre (LPSC), the lead ISRO centre working on the technology, told The Hindu.
Chemical propellants now
Functions such as orbital raising and station-keeping once the satellite is in orbit will be performed using electric propulsion, Manju S. Nair, Project Director, LPSC, said. At present, ISRO satellites employ chemical propellants for such operations.
The space agency has been working on electric propulsion so as to cut down dependence on chemical propellants. What makes the upcoming mission special is that the propulsion system has been fully developed in India. In 2017, ISRO demonstrated an electric propulsion system equipped with an 18 mN thruster aboard the GSAT-9 satellite. But in that instance, the thruster was imported while the power processing units were developed in-house by ISRO.
The new system promises 300 mN thrust and a specific impulse of around 2000 seconds with 5kW electric power supply, Dr. Nair said. The thruster works by generation of plasma, thereby generating the required thrust. The LPSC has so far completed approximately 500 hours of tests on the system and the final tests are under way.
A comparison
Compared to chemical propellants, electric propulsion is more efficient and gives you a lighter satellite for the same payload capacity. The specific impulse is five to six times higher than that of chemical propulsion.
“Which means, we can bring down the satellite mass. For example, for a 5,000-kg communication satellite which has a 900-1,000 kg ‘useful payload,’ we can bring down the total mass of the satellite to about 3,500 kg,” Dr. Narayanan said.
The 300mN thruster used for this electric propulsion system was on display at the Vikram Sarabhai Space Centre (VSSC) on Wednesday in connection with the ‘SemiconIndia 2024: Future Design’ summit. TDS-01 is scheduled to be launched aboard a Polar Satellite Launch Vehicle (PSLV) mission.
