Testing motion controllers robustness by emulating electrical and mechanical parameter variations of motor drives

The manuscript extends the method of testing the motion controllers' robustness by emulating uncertainties and disturbances, caused by real loads and mechanical and electrical parameter variations to multiloop motor drives. Such a contribution is important since multiloop drives are widely used in the industrial environment. The proposed technique requires neither connecting physical load nor actually changing any parameter of the electric drive under test. The microprocessor of the motor drive itself creates the effect of the load torque and parameter variations by applying equivalent feed-forward commands to the corresponding loop controller using digital signal processing software. As a result, the electric drive is virtually perturbed, and the controllers' behavior resembles the performance of a really perturbed drive controllers. The present method, which can be related to a class of Hardware-in-the-Loop Simulations, can be used to test the implementation of robust control algorithms or at didactic purposes using motion control kits found on the market. Simulations and experimental results validate the proposed algorithm, applied to a Brushless DC motor drive, demonstrating an excellent agreement.