Abstract
The aim of this study is to develop an energy-efficient design approach for adjustable-speed induction motor drives used in variable-capacity ventilation systems. For such applications, the use of induction motors tailored to specific operating conditions is essential. Motor optimization based on an efficiency cri-terion was performed using the DIMASDrive software (a specialized induction motor design tool), and the complete drive system was modeled in the MAT-LAB/Simulink environment. Based on the optimization and simulation results, a novel discounted cost criterion evaluated over the full operating speed range of variable-capacity ventilation loads is proposed. The criterion accounts not only for capital costs and energy efficiency, but also for the costs of reactive power and distortion power compensation, thereby reflecting both the energy performance and electromagnetic compatibility of the drive with the supply network—aspects not explicitly addressed in previously reported criteria. Structural and parametric optimization based on the proposed criterion resulted in a 19.5% reduction in the criterion value compared to a design optimized solely by the efficiency criterion, demonstrating the effectiveness and practical relevance of the proposed approach for energy-efficient drive design in ventilation applications.