根据液浮转子式微陀螺闭环驱动系统对转子转速测量的需求，提出了一种适用于悬浮转子式微陀螺的反电动势转速检测方法。根据楞次定律，永磁转子在附有检测线圈的定子中转动时，会切割磁感线感应出反电动势。对反电动势信号进行分析，即可测得转子的转速。由于检测线圈与驱动线圈共用定子铁芯，这种检测方法在降低定子结构复杂度的同时，也引入了矩形波驱动信号带来的毛刺干扰。干扰信号经过模拟低通滤波器衰减后，通过模数转换器转换为数字信号。该信号通过单片机上运行的过零检测算法处理后，即可得到当前转子的转速。测试结果表明，该转速检测系统在刷新率为4 Hz、转速达到5 000 r/min以上时，测量值的相对误差在0.3%以内，其非线性误差为0.41%,能够满足对悬浮转子式微陀螺转速进行检测的要求。

On the basis of requirements of the closed-loop driving system in a liquid suspended rotor gyroscope for measurement of rotor speeds, a Back-electromotive Force (EMF) rotating speed detection method is proposed for the suspended rotor gyroscope. As induction coils work on Lenz's law, the rotating speed of rotor can be measured by detecting the back-EMF generated by a permanent magnetism (p-m) rotor. Because the detecting coil and driving coil share the same stator core, this method reduces the complexity of the stator, but also introduces a burr interference from the driving rectangular wave. The interference signal is then attenuated by an analog low-pass filter and sampled by an A/D converter. Finally, the rotating speed of rotor can be calculated automatically by using a Micro-controller Unit (MCU) and the zero crossing detection algorithm. The test results show that the relative error of detected value can be within 0.3%, and the nonlinear error is 0.41% when a refresh frequency is 4 Hz and the rotating speed reaches 5 000 r/min. The performance meets the requirement of rotating speed detection.