Hardware design of electrostatic levitation accelerometer control system

Abstract

Abstract The electrostatic levitation accelerometer is a high-precision inertial instrument for measuring small displacement and acceleration, and it plays a very important role in global gravity field measurement, space gravitational wave detection, and other space missions as a key payload for satellites. It can realize the measurement of three-axis linear acceleration and three-axis angular acceleration. The open loop is unstable, and the control system needs to control six degrees of freedom at the same time so that the test mass can be stably suspended in the center position of the capacitive pole plate. For the demand of multi-channel simultaneous control of electrostatic levitation accelerometer, this paper designs an eight-channel digital control system hardware circuit with DSP as the core and FPGA as the co-processor, which can realize the data acquisition and feedback control of six degrees of freedom, writes the driver using hardware description language (Verilog), and simulates and analyzes the driver timing by the timing simulation software Modelsim. Finally, the hardware circuit was tested for the onboard drive. The results show that the system can work normally, the average sampling error of ADC is 0.00198 V, and the output error of DAC is 0.004 V, which is small enough to meet the system requirements.