Electronic commutation control system and control method for variable-capacitance electrostatic motor

Abstract

The invention relates to an electronic commutation control system of a variable-capacitance electrostatic motor. The electronic commutation control system comprises a rotation speed / rotation angle detecting unit, a micro controller and an output amplifying unit. The invention also provides an electronic commutation control method of a variable-capacitance electrostatic motor. The method includes the following steps that: S1, driving voltage is applied, and a rotor starts rotating at a ti time point, and the rotation speed / rotation angle detecting unit is utilized to only provide one path of rotation speed signals of the rotor; S2, the micro controller is utilized to capture the rising edge of the rotation speed signals of the rotor, and a time point at this moment is recorded as ti+1, and a rotation speed signal cycle Ti can be expressed by the equation that Ti=t(i+1)-ti, wherein i is an integer, and a rotation speed coefficient ks is set to belongs to (0, 1], and ks*Ti / 3 is set to be pulse width required by driving voltage at a next cycle; S3, the output amplifying unit is utilized to output three-phase driving voltage signals; and S4, S2 and S3 are repeated, and therefore, high-speed synchronous rotation of the rotor can be realized.

Description

technical field [0001] The invention relates to an electronic commutation control system and a control method of a variable capacitance electrostatic motor. Background technique [0002] The silicon micro-static levitation motor is processed by the MEMS bulk silicon process, and is stably suspended in the geometric center of the vacuum electrode cavity by using the electrostatic support system, which can effectively avoid contact, friction and wear, and has the advantages of high working stability and long service life. And, when the motor speed works to 10 4 It can be used as a high-precision and high-resolution two-degree-of-freedom rate gyroscope when it is above rpm. The variable capacitance electrostatic motor is a synchronous motor, when the micro motor works at 10 -1 When the vacuum condition is Pa or lower, the residual gas damping is very small, and the phase stability margin of the rotation control loop is extremely low, which will easily cause the motor to lose ...

AI Technical Summary

Problems solved by technology

The variable capacitance electrostatic motor is a synchronous motor, when the micro motor works at 10 -1 Under the vacuum condition of Pa or lower, the residual gas damping is very small, and the phase stability margin of the rotation control loop is extremely low, which may easily cause the motor to lose step and fail to work normally.

In addition, in the process of driving the micro-motor to rotate, the disturbance torque caused by temperature and air pressure changes, processing error and electrostatic bearing force coupling inside the motor will directly affect the synchronous rotation of the motor.

The traditional open-loop commutation control method does not require the current position information of the rotor, and the motor control scheme is simple, but in order to avoid the motor out of step during the acceleration process, it usually takes a long acceleration time; on the other hand, when the disturbance torque is large, It is easy to cause the rotor rotation and the stator drive pulse to be out of sync, and the motor cannot run stably for a long time

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