State Space Modeling and Simulation of Sensorless Control of Brushless DC Motors Using Instantaneous Rotor Position Tracking

This paper presents a state space modeling, simulation and control of permanent magnet brushless DC motors. By reading the instantaneous position of the rotor as an output of the state space mathematical model, the motor can be controlled without the need for any external sensors or position detection techniques. Simulink is utilized, with the assistance of Matlab, to approach a very flexible, yet reliable simulation. The simulation has two especial features. First of all, it does not exploit any block from SimPowerSystems toolbox to avoid the need for a high performance processor, large space memory and long simulation time. Secondly, the simulation allows for twenty motor specifications to be selected by the user and twenty variables to be monitored at the output. This feature helps verifying the effect of every single entry on the motor performance.