A Busbar Current Sensor With Frequency Compensation

Abstract

DC/AC yokeless galvanically insulated electric current sensors are required for applications, e.g., in automotive and aerospace engineering, where size, weight, and/or price are strictly limited. A busbar current sensor with differential fluxgate in the hole has 1000 A range and 10 mA resolution. Using an asymmetric shape, we achieved a frequency error below ±3% up to 1 kHz, while keeping high temperature stability and low sensitivity to mechanical misalignments. The 2.5 mA/°C maximum dc drift is four times better than when using an AMR sensor and 1000 times better than when using a Hall sensor. The sensor linearity error is below 0.1%.

Testing and application of an integrated fluxgate sensor DRV425

“…Several interesting applications of the DRV425 integrated fluxgate were presented by its manufacturer (Texas Instruments) and other authors [5][6][7][8]. USB interfaced probe with the DRV425 sensor was built to make the development of new applications easier, faster and more effective.…”

“…Typical fluxgates are bulky, very expensive and power consuming devices [1]. Newly developed miniaturized and integrated fluxgate sensor DRV425 [2][3][4] opens new area of possibilities in the application of fluxgates [5][6][7][8]. The dimensions of the sensor are 4 × 4 × 0.8 mm and power consumption is < 30 mW (if operated continuously).…”

Flexible-substrate Fluxgate Current Sensor Based on MEMS Technology

“…Therefore, a measurement method involving a sensor chip inside a busbar provides a practical solution in which the distance between two sensors can be adjusted to expand the measurement range and improve the measurement accuracy because of the use of multiple sensors. (28)(29)(30) In addition to the traditional current clamp sensor, which can form an open magnetic circuit, a flexible sensor can form a closed loop because it can be bent into a perfect ring. The most popular flexible current sensor is the Rogowski coil, which enables easy online measurement and is insensitive to external interference and the surrounding tested conductor but requires accurate winding.…”

Rectangular Array Electric Current Transducer with Integrated Fluxgate Sensors

“…The other problem is strong frequency dependence due to the non-uniform current distribution caused by the eddy currents in the solid bar. In [7] the busbar with modified shape to improve the frequency characteristics is shown. A similar busbar sensor with a range of 300 A is described in [8].…”