@inproceedings{HoellthalerHaglKennel2019, author = {H{\"o}llthaler, Julia and Hagl, Rainer and Kennel, Ralph}, title = {Bandwidth Improvements for Current Control Loops with a 100 kHz PWM Frequency and GaN Power Semiconductors}, series = {2019 58th Annual Conference of the Society of Instrument and Control Engineers of Japan (SICE), Hiroshima, Japan}, booktitle = {2019 58th Annual Conference of the Society of Instrument and Control Engineers of Japan (SICE), Hiroshima, Japan}, year = {2019}, abstract = {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.}, language = {en} } @inproceedings{HoellthalerHaglKennel2019, author = {H{\"o}llthaler, Julia and Hagl, Rainer and Kennel, Ralph}, title = {Bandwidth Improvements of Linear Direct Drives with a 100 kHz PWM-Frequency}, series = {2019 12th International Symposium on Linear Drives for Industry Applications (LDIA), Neuchatel, Switzerland}, booktitle = {2019 12th International Symposium on Linear Drives for Industry Applications (LDIA), Neuchatel, Switzerland}, year = {2019}, abstract = {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.}, language = {en} } @inproceedings{HoellthalerHaglKennel2020, author = {H{\"o}llthaler, Julia and Hagl, Rainer and Kennel, Ralph}, title = {Influence of the PWM Frequency on Dynamic and Position Stability of Servo Drives}, series = {25th International Symposium on Power Electronics, Electrical Drives, Automation and Motion (SPEEDAM), Virtual Meeting}, booktitle = {25th International Symposium on Power Electronics, Electrical Drives, Automation and Motion (SPEEDAM), Virtual Meeting}, year = {2020}, abstract = {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".}, language = {en} } @inproceedings{HoeltlKneisslVersen2021, author = {H{\"o}ltl, Stefan and Kneißl, Matthias and Versen, Martin}, title = {Parallel Delta-Sigma ADC modulation for performance increase of position sensors in industrial applications}, series = {2021 IEEE Sensors Applications Symposium (SAS)}, booktitle = {2021 IEEE Sensors Applications Symposium (SAS)}, doi = {10.1109/SAS51076.2021.9530099}, pages = {1 -- 5}, year = {2021}, abstract = {A parallel design concept of Delta-Sigma modulators that optimizes the resolution and the bandwidth for a highly dynamic position control in industrial applications. The idea is realized on a printed circuit board and tested by using a comprehensive measurement setup. The effective number of bits is increased by 2.5 bits at a fixed frequency. For a constant resolution, the design approach allows smaller filter lengths and a decrease of the delay by 25\%.}, language = {en} }