Efficiency enhancement of the servodrives for machine tools using adaptive pulse width modulation

• Applicant: Professor Dr.-Ing. Alexander Verl
• Subject Area: Production Systems, Operations Management, Quality Management and Factory Planning
• Term: since 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 262962563

One of the main energy consumers in production plants are components for motion generation. The servo drives used in modern machine tools generally provide a high level of efficiency. However, considering the frequently changing operating states of the machine, these devices are usually not operated at their optimal working point. In order to reduce the generating losses during unfavorable operating states and improve the economic efficiency, servo drives need to be considered as part of the entire production plant. Such a holistic approach provides the possibility for considerable energy saving in the field of motion generation.Within this project, methods for improving the energy efficiency of servo drives in machine tools will be developed using a self-adaptive adjustment of the PWM frequency. The basic idea is to adjust the PWM frequency to the current operating state of the machine tool without disadvantages in regard to stability, quality or dynamics of the machining process. In operating states with high requirements on the control quality, the operation is carried out with maximum possible PWM frequency and the best possible control parameter set. However, in operating states, in which the requirements are lower, a reduction of the PWM frequency and an automatic adaptation of the control parameters is performed, allowing for a reduction of switching losses in the semiconductors. The consequence of this approach is a significant increase in efficiency and a reduction of the energy cost during production.

• DFG Programme: Research Grants
• Co-Investigator: Dr.-Ing. Armin Lechler