New open-loop drive technology 'comes close to closed-loop'

摘要

CONTROL TECHNIQUES has devised a new method of open-loop control which, it claims, comes as close as possible to closed-loop control, without needing encoder feedback. The technique, called Rotor Flux Control (RFC), is now being incorporated as standard into the company's flagship Unidrive SP range. CT says that RFC will be a particular advantage for applications requiring a combination of dynamic performance, stability, speed accuracy, and low noise levels, without using encoders. It adds that RFC has advantages over rival technologies, such as ABB's Direct Torque Control (DTC).