【摘要】 磁悬浮球作为质量块实现惯性式振动测量,测量磁悬浮球与测振系统壳体的相对位移即可得到被测振动体的振动参数。由于磁悬浮球不与任何物体接触、无机械摩擦、无机械间隙误差,与传统惯性式振动测量方法相比具有灵敏度高、测量上限频率高,直接输出振动位移信号,通过微加工技术可实现体积小等优点,控制电路还可提供各类所需阻尼函数,但低于10 H z测量频率时需加大测试装置尺寸。在构建磁悬浮球模型及控制系统的基础上,通过对系统的结构和运行参数分析,推导了磁悬浮测振系统动力学方程,并将其等效成表征质量-弹簧测振系统的常系数二阶微分方程,使等效阻尼系数和刚度系数与质量-弹簧系统的参数有一定的对应关系。通过标准激振器产生不同的振动信号,测量结果验证了该方法正确。测试系统灵敏度:986 mV/g,测量频率范围:20 H z~5 kH z。该方法无需粘贴传感器、性价比高、操作方便。更多还原

【Abstract】 The magnetic-suspending ball as a mass block constitutes inertia vibration measurement instrument.As long as we measured the displacement parameter between the magnetic-suspending ball and the cage of the instrument,the vibration parameter of the measured object can be acquired.Because the magnetic-suspending ball has not any contact with any other objects and works without mechanical friction and mechanical gap error,the method has more advantages than the traditional inertia vibration measurement method,for example,higher sensitive,wider frequency respond,vibration displacement signals output,small.The control circuit can also furnish damping function needed.Based on the construction of magnetic-suspension ball model and its control system,under exoteric vibration,the systematic dynamical equation is deduced according to the parameters of construction and operation.The result is consistent with the constant coefficient second order differential equation of mass-spring vibration measuring system,and its equivalent damping coefficient and rigidity coefficient have a certain corresponding relation with mass-spring system parameters.A stander vibration exciter is used to make different vibration signals.The experimental results acquired by the magnetic-suspending ball vibration measuring system shows that the method is correct.The measurement system sensitivity: 986 mV/g,measuring frequency range: 20 Hz～5 kHz.The method has not any stuck sensor,has higher performance to price ratio,and operation is simple.更多还原