In recent years, brushless DC [BLDC] motor control has been gaining traction in markets where improvements in battery life are required, such as cordless power tools. This is largely being driven by demand for increased efficiency, lower noise, and higher reliability. Just a short time ago, BLDC motors used in high performance systems also required software-based microcontrollers to create efficient and quiet commutation. Newer solutions offer options with embedded commutation, offering low noise and efficient drive with no microcontroller or custom software. Sensorless sinusoidal BLDC motor drivers meet these characteristics in simple, single-package solutions that can be up to 70% smaller compared to microcontroller solutions.
Even though the fundamentals of BLDC motor control remain constant, BLDC motor characteristics vary widely across applications. Addressing differing requirements may be the biggest challenge when it comes to developing motion control algorithms. Creating specific software-housed algorithms for each application not only increases R&D expenditures, but also adversely affects time to market.
This paper will focus on the basics of the sensorless control algorithm, the advantages of different sensing techniques, and how the GUI can drive a full-featured sensorless sinusoidal BLDC motor with no software programming required.