Large dc current is typically measured by an open-loop sensor without a magnetic core. The widely used configuration uses a differential magnetic sensor inserted into the busbar hole or a differential magnetic sensor placed on the upper and lower surfaces of the busbar. The use of a differential sensor has the advantage of being resistant to external magnetic fields. In this article, a new differential ultra-small magnetic sensor with the size of 23.2 mm $\times16.5$ mm $\times7.2$ mm is designed. The sensor is based on tunneling magnetoresistance (TMR) and is placed on the upper surface edge of the busbar. The supply voltage is 5 V, the rated current measurement range is ±150 A, and the peak current measurement range is ±250 A, corresponding to 2.5 ± 2 V output at ±250 A dc peak current. The relative accuracy is less than ±1% at 25 °C and is less than ±2% over the full temperature range from −40 °C to 105 °C.

中文翻译：

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新型小体积高精度 TMR 母线直流电流传感器

大直流电流通常由没有磁芯的开环传感器测量。广泛使用的配置使用插入母线孔的差动磁传感器或放置在母线上下表面的差动磁传感器。使用差动传感器具有抵抗外部磁场的优点。在本文中，一种尺寸为 23.2 mm 的新型差分超小型磁传感器 $\times16.5$ 毫米 $\times7.2$ 毫米设计。传感器基于隧道磁阻 (TMR) 并放置在母线的上表面边缘。电源电压为 5 V，额定电流测量范围为 ±150 A，峰值电流测量范围为 ±250 A，对应于 ±250 A 直流峰值电流下的 2.5 ± 2 V 输出。相对精度在 25 °C 时小于 ±1%，在 -40 °C 至 105 °C 的整个温度范围内小于 ±2%。