Design and test of the electrostatic actuation system of the inertial sensor for space gravitational wave detection

Abstract The electrostatic actuation system is one of core control mechanisms of the inertial sensor for space gravitational wave detection, and its performance directly affects the residual acceleration of the test mass of the inertial sensor on the sensitive axis. Based on analyzing the working principle of the electrostatic actuation system and its performance requirements allocated from mission and spacecraft requirements, this paper presents the detailed analysis, design, and achieved performance of a prototype electrostatic actuation system, which consists of a set of 12-channel electrostatic actuation circuits., It has two working modes: a high-precision mode with a range of ±10 V and a wide-range mode with a range of ±150 V actuation voltage. The important problem of noise coupling between high-voltage devices and low-voltage devices is solved by a power management and output channel switching mechanism on hardware, which is an innovative solution. The test results demonstrate that the output functions of the wide-range and high-precision modes are normal, and the mode-switching process is stable. In the high-precision mode, at 10 V full-scale output, the maximum output DC voltage noise of the 12 channels is 11.8 μV/Hz 1/2 , translating to an amplitude stability of 1.18 ppm/Hz 1/2 .