On-Ground Test Method, Technology and Application of Space Electrostatic Accelerometer

Objectives: Satellite gravity measurement is the only direct means to obtain the global gravity field data. As the core payload of satellite gravity measurement, electrostatic accelerometer has the characteristics of high resolution and small measurement range. The lack of performance detection and evaluation means directly limits the development level and application efficiency of space electrostatic accelerometer in China. Methods: To meet the requirements of performance evaluation of high-precision accelerometers, research on ground test methods such as high-voltage suspension, torsion pendulum suspension, drop-tower test and development of the related technologies and devices have been carried out. The functional performance evaluation of high-precision electrostatic accelerometer series products was completed by combining various methods. Results: The high-voltage levitation test method was used to realize the long-term electrostatic suspension control of the test mass. Combined with the high-performance vibration isolation system, the ground test level reached 3×10^-9 m/s²/Hz^1/2 at 0.2 Hz. A torsional pendulum suspension test method was proposed, and the noise floor of the accelerometer reached about 2×10^-11 m/s²/Hz^1/2. And the sixdegree-of-freedom control performance of the accelerometer was tested on the ground based on a vacuum tower drop device with a height of 20 meters. Conclusions: A comprehensive test method system suitable for ground performance evaluation of high-precision space electrostatic accelerometers has been developed, which meets the needs of performance evaluation of high-precision accelerometers in the Chinese gravity satellites and other space missions.