高精度冲击波测试压电适配器的研究

Research on the Piezoelectric Conditioner for High-Precision Shock Wave Tests

针对当前冲击波测试数据峰值和比冲量不一致的问题,从传感器及其适配电路入手,研究了适配器电路的传递函数。由冲击波经验公式构造冲击波正压激励信号,分析了冲击波超压信号特征参数受压电适配器高低通截止频率的影响。结果表明,压电适配电路中高通截止频率f_(H)≤0.09 Hz,低通截止频率f_(L)≥150 kHz时,冲击波峰值误差、正压持续时间误差和比冲量误差均小于2%.按该参数设计的电路经信号发生器模拟冲击波信号测试验证了分析的正确性。分析结果为冲击波测试适配电路设计提供了依据。

To address the problem of inconsistency between peak and specific impulse of shock wave test data,we start from the sensor and its adaptive circuit to study the transfer function of the adaptor circuit.The signal constructed by the empirical formula was used as the excitation signal to analyze the effects of different band pass cut-off frequencies of piezoelectric conditioner on characteristic parameters of shock wave.The results show that the overpressure peak error,specific impulse error and positive voltage duration time error are less than 2%when the high-pass cutoff frequency of the piezoelectric conditioner is less than 0.09 Hz and the low-pass cutoff frequency is more than 150 kHz.The circuit designed according to the parameters has been effectively verified by the programmed signal generator which simulates the shock wave signal test.The analysis results provide a basis for the design of shock wave test adaptation circuit.