Refine
Document Type
- Conference Proceeding (4)
- Doctoral Thesis (1)
Has Fulltext
- no (5)
Is part of the Bibliography
- no (5)
Keywords
- bandwidth (3)
- FPGA (2)
- GaN power semiconductors (2)
- Elektrische Antriebssysteme (1)
- Leistungselektronik (1)
- current control (1)
- hochdynamische Antriebsregelungen (1)
- linear servo drives (1)
- position control (1)
- servo drives (1)
Institute
A calculation method for a robust servo controller design depending on the sampling time and the processing dead time was developed for mechanically stiff drives. With a test stand for high dynamic and high positioning accuracy, the theoretical calculations for the high bandwidth improvements are verified. The test stand includes a voice coil motor and a power electronic with Gallium Nitride (GaN) power semiconductors for switching frequencies of more than 100kHz.
A discrete-time design method for a robust current controller of a servo drive has been developed. It takes the sampling time, the processing dead time and the dynamic behavior of the A/D converter into account. The theoretical calculations are verified using a test stand for high dynamics. The test stand includes a voice coil motor and power electronics with Gallium Nitride (GaN) power semiconductors for switching frequencies of more than 100 kHz. The bandwidth of the current control loop can be improved from typically 1 kHz to 1.5 kHz with insulated-gate bipolar transistor (IGBT) power semiconductors in state-of-the-art motion control systems to 10 kHz and more.
The dynamic behavior and position stability of servo drives are influenced by many parameters. One major influencing parameter is the pulse width modulation (PWM) frequency. With inverters based on wide bandgap semiconductors, the PWM frequency can be increased. This enables a substantial increase in the current control bandwidth. The paper focuses on the influence of the PWM frequency on the dynamics of control loops and position stability, which are derived from theoretical correlations. The theory is verified using a test bench for high dynamic and position stability. The test bench is equipped with a voice coil motor and power electronic with gallium nitride (GaN) power semiconductors for switching frequencies of 100kHz and over. The achieved position stability, measured with a laser-based comparator at the tool center point, is lower than "+-1nm" with a standard deviation of "0.16nm" at a PWM frequency of "f_PWM=100kHz".
In der vorliegenden Arbeit werden die Grenzen eines Miniaturantriebs bezüglich hoher Dynamik bei gleichzeitig hoher Positionsgenauigkeit untersucht. Dabei wird das Gesamtsystem betrachtet und optimiert. Es wird ein vollständig zeitdiskretes Modell erarbeitet und die maximal mögliche Bandbreite bestimmt. Außerdem werden Einflussfaktoren wie Positionsauswertung, Digitalisierung der Rückführgrößen und digitale Pulsweitenmodulation untersucht. Es wird ein Miniaturantrieb aufgebaut, mit dem die hohe Dynamik und eine Positionsstabilität im Subnanometer Bereich nachgewiesen werden kann.