On January 5, China launched the heaviest and most technical high-orbit satellite, the practice 20, which successfully arrived at its intended job. The satellite is the first pilot satellite of the Dongfanghong-5 satellite public platform (hereinafter referred to as Dong5 platform) developed by the Fifth Hospital of China Aerospace Science and Technology Group.
Li feng, chief designer of the fifth institute's practice 20 satellite, said that the satellite had now completed the shift of orbit, verified the main key technologies of the east five platform, and the first flight of the east five platform was successful. Follow-up on-orbit testing and validation will continue.
The reporter learned from the practice 20 satellite flight control test team of the Fifth Hospital that the satellite has completed a series of high-difficult movements in nine days since its launch on December 27,2019, and carried out a series of new technology in-orbit test verification, and achieved important test results. Includes:
China's largest area, the most complex expansion of the solar wing, completed the \"one expansion\" and \"two-dimensional expansion\" action. Real 20 has a giant solar wing 10 metres wider than the wingspan of a Boeing 737. As the first \"taut-string\" solar wing in China, the weight of the electromechanical part decreased from 1:1 to 1:2 in the previous model, and the mechanical and electrical weight ratio was the lowest in history. Such a huge, lightweight solar wing is also unusual in its way.
The satellite didn't need much energy at the beginning of its orbit, so the solar wing was \"unfolding at one time \", expanding only a fraction. About a week after the space flight, the satellite reached a geostationary orbit about 36000 km above the ground, and the solar wing also implemented a \"two-dimensional expansion \", all of which greatly increased its area.
Practice satellite 20 to complete 7 orbit changes. Before reaching geostationary orbit, the satellite underwent seven orbital maneuvers. The main role of the orbit maneuver is the chemical propulsion system, whose most important task is to replace the launch vehicle and use the high-performance chemical propulsion system to send the satellite to its intended working orbit. Track maneuvering is a comprehensive assessment of the main performance of the chemical propulsion system. In these seven track maneuvers, the chemical propulsion system performs well.
Follow-up, the practice of satellite 20 electric propulsion system, will take the baton, to help the satellite precise \"stay\" in the fixed position. The chemical propulsion system will be \"second-tier\" and will top when needed.
vector adjustment mechanism unlocked successfully. On january 4, the practice satellite 20 successfully completed the first operation of the biaxial vector regulating mechanism in orbit, and the four mechanisms were successfully unlocked and turned to the target angle with high precision, which laid a solid foundation for the successful ignition of the subsequent electric propulsion system.
Vector regulating mechanism is a key product to realize the maximum effect of satellite electric propulsion system, which can adjust the direction of engine thrust. Since then, the electrical propulsion system has ignited in accordance with the satellite mission plan, and will continue to carry out position-keeping and momentum-wheel unloading missions throughout the lifetime of the satellite, ensuring that the satellite remains in place.
the laser terminal is unlocked successfully in orbit. On january 4, the practice 20 satellite laser terminal in orbit unlocked successfully, immediately carried out a wide range of rotating mechanism function inspection, the product is in good condition. The product will carry out a series of experiments such as high-speed coherent laser communication, further accumulate engineering data of satellite laser communication link, lay a technical foundation for the subsequent development of higher-speed laser communication load, and meet the needs of high-speed inter-satellite and inter-satellite information transmission.
The East Fifth Platform is a new generation large-scale geostationary orbit satellite platform developed independently in China. According to the design indicators, the take-off weight of satellites based on the East Five Platform can reach 8 to 9 tons, and the load carrying capacity can reach to tons; the whole star power is over 28 kilowatts, and the load power is 18 kilowatts; the heat dissipation capacity of the load compartment is 9 kilowatts; and the design life is 16 years.
More importantly, the platform can meet the needs of different functional satellite development, and can be widely used in high-orbit communication, microwave remote sensing, optical remote sensing, space science exploration, scientific testing, in-orbit services and other fields, is a rare multi-adaptive platform in the world space field.
Academician Zhou Zhicheng, chief engineer of the Fifth Hospital, commander-in-chief of the practice 20 satellite and commander-in-chief of the East Fifth Platform, introduced that compared with the main products in active service in China, the East Third and East Fourth Platforms, the East Fifth Platforms have a leapfrogging in key performance indexes such as weight, power and life, which will fill the gap of large-scale satellite platform spectrum in China and meet the needs of large-capacity satellite applications in the next 20 years.
In addition, the East five platform also innovates the design idea, realizes the intelligent independent operation management, thus effectively enhances the satellite's good use, the ease of use; through the compartment modular design and the digital development pattern, greatly shortens the development cycle, effectively enhances the design production efficiency. The single-machine localization rate of the platform reaches 100%, which will be a powerful traction for the development of space equipment in China.
Reporters learned that the practice of satellite 20 will carry out practical on-orbit testing work to further verify the key technologies of the platform. (Hong Kong, Hong Kong)