一款基于18位ADC的高精度三相标准表的设计

针对国内高准确度三相标准电能表稀缺,而进口高准确度表价格又相对昂贵的这样一种状况,设计了一款基于18位ADC的高准确度标准电能表。另外,利用电流互感器的有源补偿技术,使电流采样的线性度和稳定度好;利用电源隔离技术,噪声干扰小,信号稳定;采用低温漂进口箔电阻进行信号取样,长期稳定性好;每个周波1 024点采样,且运用逐点处理方法进行电量计算,数据更新快,实时性好,测量准确度高。综合各方面先进技术和高品质器件,经试验表明,这款三相标准电能表的准确度等级能达到0.01%以内。

Design of high-precision three-phase standard meter based on 18 bits ADC

In view of the situation that high-precision three-phase standard electric energy meter is scarce in our coun-try, while the price of imported high-precision meter is relatively high , so a kind of high-precision standard electric energy meter based on 18 bits of ADC is designed .In addition , the linearity and stability of current sampling become better via the active compensation technique of current transformer;the noise jamming is little and signal is stable via power isolation technique; low-temperature offset inlet foil resistance is adopted for signal sampling , and long-term stability is good;sampling is carried out for 1 024 bits every cycle wave , and point-by-point processing method is ap-plied for electric quantity calculation , thus, fast data updating , good real-time, and high measuring accuracy can be obtained .Combining advanced techniques of various aspects and high-quality devices , as per experiment , the accura-cy class of this type of three-phase standard meter for electric energy can reach as high as within 0.01 class.