Low-resolution and low-cost position sensor implementation for permanent magnet synchronous motor driver

Permanent magnet synchronous motors (PMSM) are recently getting involved in many usage areas such as industrial, robotic, home and office applications due to the fact that they have several advantages like fast dynamic response, low size, high efficiency, high power density and more reliability. Since PMSMs require rotor position information for phase current commutation, a position encoder is used on the rotor. Unfortunately, position sensor increases the size and cost of the driver system. In this study, a simple low cost position sensor based on photomicrosensor is proposed to replace the position encoder. A driver system for 12 poles PMSM with developed position sensor was set up and tested under different speed and load conditions. The experimental results proved that the PMSM driver is able to deliver sinusoidal currents to stator phase windings along with demonstrating the effectiveness of the proposed sensor.