Simulation and rapid control prototyping of DC powered universal motors speed control: Towards an efficient operation in future DC homes

Abstract

Universal motors are widely used in household appliances. When traditionally powered by AC, current harmonics are created which cause overheating of the windings and electromagnetic compatibility problems affecting the lifespan of the motor. Considering the remarkable comeback of DC power and its prospects in the electrification of homes, this paper proposes a control strategy for universal motors powered by DC using the rapid control prototyping feature offered by the dSPACE MicroAutoBox. A PI controller is designed using dominant-pole compensation method. The control strategy is simulated in Matlab/Simulink, then implemented in the MicroAutoBox via the Real-Time Interface. The simulation results are compared with those acquired by implementation through a laboratory test bench built around the MicroAutoBox and a dual full-bridge driver. The experimental results show that the designed PI controller managed to eliminate the static error and increased significantly the system dynamic performance by 26.5% in simulation and by 23.5% in practice. The robustness of the proposed control strategy against randomized load disturbances is proved by experimental tests. Furthermore, a significant improvement in power quality is reported.

Keywords

• Digital signal processor
• Universal motor
• Speed control
• Hardware architecture
• PI controller
• dSPACE MicroAutoBox