Research on Temperature Compensation Method for CRAFT Dot Matrix Hall High Current Sensor

To meet the measurement needs of high current in the comprehensive research facility for fusion technology (CRAFT) power supply, a non-magnetic core direct measurement dot matrix Hall high current sensor has been developed. Hall elements have high sensitivity and wide measurement linear range characteristics, making them suitable for high current measurement occasions. As a semiconductor component, the resistivity, mobility, and carrier concentration of its semiconductor material are all functions of temperature, which can cause changes in parameters such as Hall potential, sensitivity coefficient, and internal resistance with temperature, thereby affecting the sensor’s measurement accuracy. Therefore, the temperature compensation method must be taken to ensure signal measurement accuracy. The traditional constant voltage source input compensation method ignores the internal resistance of the constant voltage source. The constant current source input compensation method ignores the quadratic term of temperature change. Both of them are incomplete compensations. This article proposes a constant current source dual compensation method based on two compensation methods. The constant current source dual compensation method can further improve the temperature characteristics of the sensor and enhance the adaptability of the dot matrix Hall current sensor to the environment. According to the simulation and on-site experimental results, the proposed constant current source dual compensation method can effectively reduce the influence of temperature on the parameter error of Hall elements, thereby significantly improving the sensor’s measurement accuracy.