Mittuniversitetet

In this thesis, the electromagnetic design of high current measurement based on the Hall sensor is studied. The multiphase (22 phases) winding in a low-voltage (48V) high power density motor has large currents, small internal spaces, and a complex coupling magnetic field. In this case, a small volume, high precision device is necessary for the winding current measurement.  Based on the Hall effect principle, the interference resistance and nonlinearity of circular array differential and open-loop differential Hall sensors are analyzed and compared. The finite element modelling and simulation is used to study the influence of the adjacent current-carrying copper pipe on the sensor's accuracy. The interference of the skin effect on the sensor is analyzed at different frequencies. The comparison results show that the differential circular array sensor fits the current measurement requirement of small-volume and high current AC motors. A 1 kA differential circular array Hall sensor is designed and proofed. The 1 kA test platform is assembled, which tests the sensor accuracy, temperature drift and response delay. The result shows that the Hall sensor has good thermal stability, low response delay, and the low frequency accuracy is 0.0879%. This design can provide a reference for the design of high-precision, small-size, and wide-range current sensors.