A mixed-signal co-simulation environment for brushless DC motors

The well-known electromechanical motor model applied to permanent magnet motors relies on several simplifications which seriously limit its ability to rigorously model state-of-the-art sensor-less drives. Two distinctive assumptions made in its derivation are that saturation effects imposed by the magnetic core are neglected and that the motor is assumed to be non-salient. As a consequence, modern position detection methods used in standstill or during start-up in sensor-less control systems cannot be simulated, verified, or optimized with such a model. The overcome these drawbacks, we significantly extend the classical motor model by incorporating nonlinearities caused by saturation effects in the core. It this contribution, we report on this novel model and demonstrate its applicability for correct verification of sensor-less control methods using reactance measurements for angular rotor position detection.