Miniaturization of Inertial Magnetoelectric Vibration Velocity Sensor with High Frequency Response at Low Frequency Band

The frequency response of the inertial magnetoelectric vibration velocity sensor is limited in the low frequency range due to the character of second order high pass filter of the structure. For better performance in the low frequency range, the traditional method is to increase the initial mass of the sensor which will increase the size and weight tremendously. This paper presents a frequency-selected compensation network to improve the performance of the frequency response at low frequency band, keeping the sensor in small size and light weight. The frequency-selected network, which is composed of amplifiers, resisters and capacitances, is connected to the output port of the sensor in cascade without any modification of the sensor’s structure. After compensation, the frequency band of the sensor is flattened and the frequency response still has the character of second order high pass filter while the resonant frequency decreases from 10Hz to about 0.9Hz. The experimental results have shown that the sensor after been compensated has good performance in the low frequency range.