用于宽频带脉冲测量的平板电容传感器设计

Design of Flat Capacitive Sensor for Wideband Pulse Measurement

为了克服小尺寸平板类电容分压器测量频带普遍较窄的缺点,设计了一种包含积分器和阻抗变换器的平板电容传感器。该平板电容传感器采用直径100 mm的小尺寸同轴型结构,平板探头与引出电缆连接段隐藏在"凸"字形屏蔽腔体内,可以有效降低自身电感与外界干扰。电缆引出端连接所设计的积分器和阻抗变换器,进行对信号的还原以及对下限截止频率的优化。经过试验标定与数据分析,该平板电容传感器具有10 Hz^150 MHz的测量频带,能满足陡前沿和长波尾的波形测量。

In order to overcome the shortcomings that the measuring bandwidth of small size flat capacitive divider is generally narrow, we introduce a flat capacitive sensor contains integrator and impedance converter. The flat capacitive sensor adopts small coaxial structure of which diameter is 100 mm. And the connecting segment between the flat probe and the outgoing cable hides in the shielding cavity which is convex. This could reduce the self-inductance and the interference effectively. The outgoing cable connects to the designed integrator and impedance converter, restoring the signal and optimizing the low-cut-off frequency. Through the experiment and the data analysis, the bandwidth of the flat capacitive sensor is 10 Hz-150 MHz, and it can be used for measuring the steep front pulse and long tail pulse.