非线性校正在数字矢量化LCR中的运用

Application of nonlinear correction method in digitized LCR

针对数字矢量化LCR放大调理电路的非线性影响,而导致激励输出的不准确问题,提出了一种针对矢量LCR放大电路的非线性校正模型方法。该方法能在频率、幅值方向进行两维校正,通过校正达到降低放大电路非线性的影响,提高激励输出的准确度的目的。为了验证设计方法的有效性,以某LCR为校正平台,进行方法模型验证,试验结果表明,利用该方法得到很好的幅值输出控制精度：在低频条件下,基本可控制在1%以下,很好地验证了提出方法的可行性;在高频条件下,因电路中引入寄生阻抗,如寄生电容、寄生电感,容易引起误差,但基本也在1%以内,由此说明该方法的有效性。

Aiming at the nonlinear effect of digital LCR amplification and conditioning circuit,which leads to the inaccurate problem of excitation output,a nonlinear correction model method for vector LCR amplifier circuit was proposed.This method could be corrected in the frequency and amplitude direction,and improved the accuracy of the excitation output by reducing the nonlinearity influence of amplifier circuit.In order to verify the effectiveness of the design method,a LCR calibration platform was used to test,the result show that using this method to get a good accuracy of amplitude output control：in the low frequency conditions,the basic control can be less than 1%,agood way to verify the feasibility of the proposed method;and in the high-frequency conditions,due to the introduction of parasitic impedance in the circuit,such as parasitic capacitance,parasitic inductance,easily lead to errors,but basically within 1%,it indicated the effectiveness of the method.