PCB空心线圈电流变换器研制

Current-voltage converter based on PCB air-core coil

目前,微机保护装置以及电子式电能表采用的都是传统的带铁心的电流变换器,传统的电流变换器存在磁饱和问题,测量动态范围窄,为此提出了一种PCB空心线圈电流变换器,该PCB空心线圈电流变换器的次级线圈采用了对称设计,最大限度地消除了外界电磁干扰造成的误差;初级线圈可视情况绕制成多匝,并可通过位置的调整改变与次级线圈的耦合程度,从而改变传感头的互感系数。电流变换器制作简单方便,体小质轻,测量频带宽;对制作的样板进行了实验验证,结果表明PCB电流变换器达到了一定的测量精度,在较大的动态范围内具有良好线性度,且响应速度快。

At present,most of microchip-based relay protections and electronic watt-meters adopt the magnetic -core current transducer with narrow dynamic metering range and serious magnetic saturation,for which a PCB-style current-vohage converter is presented. It has four symmetrical secondary spiral coils on the same surface with air-core to eliminate the impacts of outside magnetic field by the greatest degree. Its primary line may have multiple turns if necessary and the position be adjusted to obtain needed mutual inductance. It is small,light and easy to manufacture. A prototype is tested and the results show its high accuracy,good linearity,wide dynamic metering range and quick response.