Method, device and system for measuring mechanical beam rigidity of capacitive MEMS accelerometer

The invention relates to a method, a device and a system for measuring a mechanical beam rigidity of a capacitive MEMS (Micro-Electro-Mechanical System) accelerometer. The method comprises: applying apreload voltage to the accelerometer, wherein the preload voltage comprises a first preload voltage and a second preload voltage; acquiring a first voltage change amount output by the accelerometer at the first preload voltage when the acceleration experienced by the accelerometer changes, and acquiring a second voltage change amount output by the accelerometer at the second preload voltage whenthe acceleration experienced by the accelerometer changes; and obtaining the mechanical beam rigidity of the accelerometer according to a first electrostatic negative rigidity of the first preload voltage, a second electrostatic negative rigidity of the second preload voltage, the first voltage change amount and the second voltage change amount. According to the method, the device and the system for measuring the mechanical beam rigidity of the capacitive MEMS accelerometer, the influence of the parameters, of the traditional measuring technology, such as displacement capacitance conversion coefficient, inertial mass block quality, etc., on the measurement precision when measuring the mechanical beam rigidity can be avoided, so that the measurement precision of the mechanical beam rigidityof the accelerometer is improved.