Application-oriented design of mechatronic drive trains

The scope of this paper is to establish a method to analyze, design and test mechatronic drive trains based on the application requirements concerning efficiency and energy consumption. The considered drive train consists of frequency inverter, electric motor and gearbox. A standard three phase two-level inverter with two different machine control strategies (constant torque angle CTA and maximum torque per Ampere MTPA) and two different PWM logics (third harmonic injection method and space vector modulation) is considered. As type of the electric machine the permanent magnet synchronous motor (PMSM) with surface mounted magnets or interior magnets is chosen. Additionally, spur, bevel worm and planetary gearboxes can be modeled with this approach. To determine the efficiency a basic model for all components is developed to calculate the respective losses. Finally, an optimization tool is introduced to increase the energy efficiency of an application load cycle by determining the optimal gear ratio for a given frequency inverter and electric motor combination. Finally, the model is used in a case study to calculate the optimal gear ratio by using different types of gearboxes.