一种宽量程高精度绝缘电阻测量仪设计

为实现宽量程高精度的绝缘电阻测量，提出一种将积分静电计与比例电阻法相结合的具自校正功能的高阻测量方法。首先，根据不同量程高阻测量的主要误差特点，按被测电流大小选择不同的测量模式实现在10^5-10^9Ω范围内的高精度测量；其次，针对微电流条件下的超高阻测量，研究一种具误差抑制功能的高阻检测算法，抑制由于测量系统固有泄漏电流和由于分布参数引起的非线性干扰电流造成的误差，有效地将微电流测量下限扩展到0．1pA，实现在1000V高压激励下对高达10MQ元件的测量。实验结果表明，系统在10^5-10^9Ω范围内测量准确度小于-0．5％，相对测量不确定度（包含因子k=2）小于0．04％，在10^9-10^12Ω范围内测量准确度小于4-1％，相对测量不确定度（拓2）小于0．2％，在10^12-10^15Ω范围内测量准确度小于±5％，相对测量不确定度（妊2）小于0．6％。其整体性能已接近国际先进水平。

Design of high precision IR meter with broad range

Abstract： To realize the measurement of high precision insulation resistance（IR） with broad range, a high resistance measuring method with self-correction function is proposed, which is composed of integral electrometer and proportion resistance. Firstly, the mode is selected in range from 10^5 to 10^16Ω according to the error characteristic of different high resistance range. Secondly, a weak current test algorithm with error suppression is also put forward, which can expand the low current measurement limit to 0. lpA and greatly decrease the error produced by the inherit leakage current in system loop and the nonlinear interference current due to the distribution parameters. Thus, the IR components up to 10^16Ωcan be measured under 1000V stimulation. The experimental results show that the relative error is less than ±0.5% with rela- tive uncertainty （k=2） less than 0.04% in 10^5-10^9Ω, the relative error is lower than ±1% with relative uncertainty （k=2） less than 0.2% in 109~1012~2, and the relative error is less than ±5% with relative uncertainty （k=2） less than 0.6% in 10^12-10^15Ω. The measurement performance is close to the international advanced level.