基于Rogowski线圈的数字积分器的研究与设计

Research and design of digital integrator based on Rogowski coil

积分器是影响基于Rogowski线圈电流互感器精度的关键环节。对模拟积分器的温度特性进行了分析,理论分析和实验结果表明其受温度的影响较大。和模拟积分器相比,数字积分器具有更高的精度和稳定性。利用梯形公式进行数字积分,分析与仿真了梯形积分算法对稳态和暂态电流的响应,提出了解决积分中漂移、初值问题的措施。设计了基于STM32F103的数字积分器,并利用新型PCB平面Rogowski线圈电流互感器进行了实验。实验结果验证了设计方法的有效性。

Integrator is the key element of electronic current transducer based on Rogowski coil. The temperature characteristics of analog integrator are analyzed. Both theoretic analysis and experimental data indicate the temperature is its most influencing factor. Digital integrator has better accuracy and higher stability than analog integrator. Trapezoidal formula is applied in digital integral algorithm and its responses to steady and transient currents are analyzed and simulated. Measures to deal with the drift and initialization of digital integrator are proposed. A digital integrator based on STM32F103 is designed and tested with the new-style PCB planar Rogowski coil current transducer. Its validity is proved by experimental data.