A microcomputer controlled ICPT power pick-up and its EMC considerations for moving sensor applications

This paper presents a microcomputer controlled inductively coupled power transfer (ICPT) power pick-up circuit for moving sensor applications. The new software based control schemes are compared with the existing analogue ones. The flexibility of using the software over the hardware in changing control variables and control schemes is demonstrated. The required power transfer capacity and the correct operating voltage for the moving sensor are obtained using a new microcomputer controlled power pick-up. Furthermore, EMC (electromagnetic compatibility) concerns of the moving sensors under such a switched mode power supply are investigated. The harmonic spectrums of different control strategies are compared and the PWM (pulse width modulation) control with a fixed fast-switching frequency is found to be a better solution in terms of EMC filtering design. This work is particularly important in designing a contactless power supply system for moving sensor applications.