Prof. Dr.-Ing. Prof. Stefan Soter
Contact us:
Rainer-Gruenter-Str. 21
42119 Wuppertal
Room: FH.01.07
Stefan.Soter[at]uni-wuppertal.de
+49 202 439 1950
For requests please contact my Secretary
Personal career
10/1984 to 11/1989 University of Bochum; Degree: Dipl.-Ing. Electrical Engineering
01/1990 to 04/1996 Distance University Hagen Institute Solatec (Prof. Dr.-Ing. D. Hackstein)
01/1994 Doctorate (Dr.-Ing.) in Electrical Engineering
Topic of the dissertation: "System technology for photovoltaically fed asynchronous machines for driving water pumps".
05/1996 to 03/2007 Technical University of Dortmund (Prof. Dr.-Ing. Dr.-Ing. S. Kulig) Chair of Electrical Drives and Mechatronics, formerly Chair of Electrical Machines, Drives and Power Electronics
scientific assistant, senior engineer (from 07/1997), academic councilor (from 03/2001), academic senior councilor (from 03/2004)
since 04/2007 freelance manager of industrial projects in cooperation with the University of Wuppertal, Chair of Electrical Machines and Drives, Prof. Dr.-Ing. Ralph Kennel
04/2005 Offer of the W3 deputy professorship "Power Electronics" of the Helmut-Schmidt-University Hamburg
from 10/2008 Lectureship at the Rheinisch-Westfälische Technische Hochschule Aachen (RWTH) (Prof. Dr.-Ing. Dr. h.c. dr hab. Kay Hameyer) Institute for Electrical Machines. Lecture title: Design and grid operation of wind turbines
10/2008 to 02/2010 W3-professorship for "Electrical Machines and Drives" at the University of Wuppertal, Germany
from 03/2010 W3-Professorship for "Electrical Machines and Drives" of the University of Wuppertal
Lectures
- Fundamentals of Electrical Engineering III
- Controlled electrical drives
- Power electronics
- Wind turbines
Publications
- 57.A. Bartsch, F. Senicar, S. Kratz and S. Soter, "Enhanced FPGA based three level space vector pulse width modulation with active neutral point balancing" in 2013 IEEE Energy Conversion Congress and Exposition, 2013, pp. 1748--1753.
ISBN: 2329-3748
Abstract:
This paper presents an FPGA based implementation of an improved space vector pulse width modulation for neutral point clamped three-level topologies. For this purpose the flatspace modulation calculating the timings is used in combination with an optimized switching pattern to reduce the switching edges to a minimum. Additionally a combination of two methods for balancing the neutral point is developed which are both implemented without adding any additional harmonics to the modulated output. - 56.F. Senicar, A. Bartsch, K. Klitzke and S. Soter, "Improved high bandwidth current controller for FPGA based inverter drives" in 2013 IEEE AFRICON, 2013, pp. 1--6.
ISBN: 2153-0033
Abstract:
This paper presents the improvement of the precision and bandwidth of the current control loop implemented in a field programmable gate array (FPGA) based inverter. By compensating the nonlinear effects of the IGBT power stage with a feed forward control, the current controller is relieved resulting in an output current with less harmonics and a better frequency response. In order to improve the current control loop even further, a current observer, based on a Luenberger observer is implemented. - 55.S. Gruber, B. Krüger and S. Soter, "High force tubular linear actuator with integrated eddy current brake for spring-loaded systems" in 2013 IEEE AFRICON, 2013, pp. 1--5.
ISBN: 2153-0033
Abstract:
In order to meet safety standards in manufacturing industry many production machines are equipped with safety stop functions based on spring-loaded systems. This paper deals with an integrated eddy current brake of a high force tubular permanent magnet linear actuator for hydraulic applications with small actuating pathes. An analytical description of different design criteria for the integrated eddy current brake are shown. The special not rotational symmetrical design of the tubular linear actuator is transferred to a 2D transient FEM simulation model to predict the braking behavior caused by the spring load in case of an emergency stop. Measurements on a test bench are in good agreement with the simulation results and are used to validate the model. - 54.B. Krüger, S. Gruber and S. Soter, "Controlling of medium voltage power-factor of photovoltaic power plants from the low voltage side" in 2013 IEEE Energy Conversion Congress and Exposition, 2013, pp. 569--574.
ISBN: 2329-3748
Abstract:
The effort to make the production of electrical energy much more environmental-friendly, large conventional power plants will be replaced by several smaller regenerative power plants. In order to improve stability and controllability, these smaller power plants are supposed to control the active power, the reactive power and the power factor in the medium voltage grid like conventional power plants. This paper will discuss three different methods to control the medium-voltage power factor from the low voltage side in consideration of parasitic effects from cables and transformers to fulfill the guidelines at the grid connection point. A method with a self-learning-algorithm will be implemented and proven by simulations and measurements on a test bench with inverter and 400 V to 10 kV grid transformer. The self-learning-algorithm will give the opportunity to reach every required power factor at the grid connection point. - 53.A. Uphues, K. Nötzold, R. Wegener, S. Soter and R. Griessel, "Inverter based voltage sag generator with PR-controller", 2012, pp. 1037--1042.
Abstract:
Due to the increasing wind power penetration, grid codes of system operators require low voltage ride through (LVRT) capability for wind turbines (WT). Additionally the WT has to support the power system stability in LVRT cases. To evaluate the LVRT capability of grid connected converter, a voltage sag generator (VSG) is required to emulate grid failures. This paper introduces a three phase programmable inverter based VSG, which is equipped with a cascaded control structure consisting of proportional resonant (PR) current controller and PR voltage controller. The described VSG is able to emulate all required voltage sags, propagated through a delta star connected transformer, very precisely. The control structure has been simulated and tested successfully on a 2MW full power testbench. - 52.A. Bartsch, F. Senicar and S. Soter, "Design of a scalable FPGA based inverter for complex drive systems" in 2012 IEEE International Conference on Industrial Technology, 2012, pp. 1086--1091.
Abstract:
This paper presents the design and implementation of motor control peripherals on a field programmable gate array (FPGA) in conjuction with a microcontroller, forming a powerful and flexible computing platform for inverter drives. The implementation of a vector controlled pulse width modulation, an encoder interface and a current measurement unit are described. Furthermore a current control unit is implemented on the FPGA in order to relieve the microcontroller from some high frequency real-time tasks. The FPGA and the microcontroller form a flexible control board which is used for different projects including high speed multi level inverters and four quadrant drive systems. Furthermore multi axes systems can be implement without any performance drawbacks and just a moderately increased effort optimizing the use of an FPGA. - 51.S. Gruber, R. Wegener and S. Soter, "Detent force reduction of a tubular linear drive by using a genetic algorithm and FEM - verification of simulation results" in IECON 2012 - 38th Annual Conference of the IEEE Industrial Electronics Society, 2012, pp. 1731--1736.
Abstract:
In order to meet industrial safety standards in eccentric presses, the detent force caused by the reluctance change between permanent magnet (PM) and stator teeth of the acting high force tubular permanent magnet linear synchronous machines (PMLSM) should be reduced. The detent force is generated by two components: the slot effect which is already decreased by the closing slot technique and proven in [3] and the end effect which will be optimized by using auxiliary poles at the end of the machine. Therefore a special genetic algorithm (GA) is developed which rates the simulation results of the FEM and produces new auxiliary poles. The combined simulation tries to find an optimal size and position for auxiliary poles to reduce the whole detent force. The numerical calculations propose a minimized detent force caused by the located poles, which is independent from the length of the machines (1 to 5 modules). The result will be proven by measurements. - 50.F. Senicar, A. Bartsch, B. Krüger and S. Soter, "Enhanced bandwidth current controller for FPGA based inverter drives - a detailed analysis and implementation" in IECON 2012 - 38th Annual Conference of the IEEE Industrial Electronics Society, 2012, pp. 1775--1780.
Abstract:
This paper presents the optimization of the current control loop implemented in a field programmable gate array (FPGA) based inverter. The bandwidth of the current controller is significantly enhanced by reducing the delay times to its theoretical minimum. The optimizations are at first analyzed on a theoretical basis and afterwards verified on the actual target system. It is discussed, that the optimized current controller can be implemented without any drawbacks in terms of available output voltage. It is shown, that the significant reduction of delay times can be implemented in practice, greatly enhancing the bandwidth of the current controller, thus allowing a much higher controller gain. - 49.A. Uphues, K. Nötzold, R. Wegener and S. Soter, "PR-controller in a 2MW grid side windpower converter" in 2012 IEEE International Conference on Industrial Technology, 2012, pp. 1073--1078.
Abstract:
To regulate the current in grid connected power converters mostly proportional integral (PI) controller in synchronous reference frame are used. To improve their known drawbacks such as complexity of control structure because of the dq-transformation and the poor behavior concerning low order harmonics compensation, proportional resonant (PR) controller gained a large popularity. This paper describes the differences between using PI-controller and PR-controller in a 2MW grid connected power converter for wind turbines. The control theory of PR filters and implementing them as delta based infinite impulse response (IIR) filters in a fixed-point microcontroller is presented. The PR-controller with harmonic compensation has been tested in a 2MW power converter. - 48.C. Junge, T. Ruhland, S. Gruber, R. Wegener and S. Soter, "Controlled input-output-shaft synchronisation by a linear drive actuated hydraulic clutch-brake-combination" in 2011 IEEE AFRICON, 2011, pp. 1--5.
Abstract:
The focus of this paper is the control to accelerate and decelerate a drive shaft exactly with a hydraulic clutch-brake-combination (CBC). The CBC is actuated by a permanent magnet linear synchronous machine (PMLSM) with an integrated hydraulic cylinder. The servo-converter-controlled-PMLSM is able to generate the pressure for the CBC. A superposed control cascade with a pressure control and a special synchronization control is implemented to vary the transmitted torque and therefore the accurate acceleration and deceleration of the drive shaft within a preset angle. This development ensures a controlled synchronization of the input-output shaft by a CBC in a specific point of time within a preset mechanical angle.
