A temperature compensated power measurement system based on a Hall effect sensor

This paper introduces the use of a Hall effect sensor as the main part of a microcontroller-based power measurement system. The system is designed around 8 bit microcontroller PIC16F84 that performs the acquisition, processing and display of sensor´s data. In order to reduce the undesired influence of the temperature on system´s accuracy, an additional temperature sensor (ON-400 thermistor) and a temperature correction software component are introduced. Referring to the analog to digital conversion of the sensor data, a two-channel pulse-width modulated scheme is implemented based on microcontroller´s digital input-output lines. The instantaneous power is displayed using a LCD display controlled by a Hitachi 44780 controller.