Servo control of solenoid actuators using augmented feedback linearization

摘要

Solenoids are commonly used in fuel injection systems, in process automation, medical systems, etc. They have numerous advantages: they are fast, reliable, compact and produce a high force output, making them a competitive replacement option for purely mechanical actuators and pneumatic control valves. However, their coil inductance and electromagnetic force vary non-linearly as a function of position and controlling their position can be a significant challenge - conventional PI, PD, PID controllers fall short of providing acceptable performance. This work aims at developing a servo control scheme for the solenoid using an Augmented Feedback Linearization (AFL) based approach. The AFL controller includes classical current regulation, a reduced-order feedback linearization and error integration. The control scheme is formulated and a multirate state feedback motion controller is designed to achieve closed loop position regulation. The control algorithm is verified using experimental results and shows superior performance over classical control techniques.