40.

S. Gruber, C. Junge, R. Wegener and S. Soter, "Reduction of detent force caused by the end effect of a high thrust tubular PMLSM using a genetic algorithm and FEM" in IECON 2010 - 36th Annual Conference of the IEEE Industrial Electronics Society, 2010, pp. 968--973.

Abstract:
In order to meet industrial safety standards in eccentric presses, the detent force of the acting high force tubular permanent magnet linear synchronous machines (PMLSM) should be reduced. The detent force is caused by two components: the slot effect and the end effect. Both effects are based on the reluctance change between permanent magnet (PM) and stator teeth. The slot effect is already optimized by the closing slot technique which is proven by measurements presented in this paper. The main topic is the reduction of detent force 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 (2, 3 or 5 modules).

39.

K. Nötzold, A. Uphues, R. Wegener and S. Soter, "Highly integrated inverter with multiturn encoder and software-based PFC for low cost applications" in 2010 IEEE International Conference on Industrial Technology, 2010, pp. 764--768.

Abstract:
Motor control gets more and more common in fields where it was not applicable a few years ago. The prizes for computing power due to higher integration of the power electronics are going down. Because of this, brush-less DC and permanent magnet synchronous machines capture new markets and replace simple grid connected induction machines. The rising standards for electromagnetic interference (EMI) emissions make a power factor correction (PFC) in a lot of applications necessary. In addition a PFC offers some advantages because of the DC bus regulation. In this paper an inverter with a particularly low prize and a high performance is presented. A software based PFC is integrated into the motor control circuit and a low cost absolute position encoder has been developed. In addition some synergetic effect between motor control and PFC will be shown. The experimental results show the feasibility of the integration of a field orientated control with an integrated PFC in one low cost microcontroller.

38.

F. Senicar, C. Junge, S. Gruber and S. Soter, "Zero sequence current elimination for dual-inverter fed machines with open-end windings" in IECON 2010 - 36th Annual Conference of the IEEE Industrial Electronics Society, 2010, pp. 853--856.

Abstract:
A dual-inverter allows to increase easily the maximum available power of a given inverter. When connecting two equal inverters to a machine with open end windings, the available power will raise by factor $\surd$3. However, the dual inverter also introduces a new degree of freedom for the current, which is the zero component current. The dual inverter is known for developing zero component currents, which have three times the frequency of the fundamental current, and can be of a rather large amplitude. This paper analyses the origin of these zero component currents and shows an example of how to eliminate them. Moreover it shows the possibility to suppress zero component currents by using only software algorithms modifying the current control loop. There is no need for extra components. Moreover there are no drawbacks in the quality of control as well as regarding the maximum available voltage.

37.

A. Bartsch, S. Gruber, R. Wegener and S. Soter, "Testbench for electrical drive systems in hybrid applications" in 2010 IEEE International Conference on Industrial Technology, 2010, pp. 1136--1140.

Abstract:
This paper deals with the development of a test bench for mild hybrid drives used in construction machines. Due to the special conditions under which construction machines are operating this test bench needs to be adapted. Hence the bearing of the electrical drive, which is mounted directly to the internal combustion engine, the temperature control by a cooling circuit and the integration of an appropriate inverter as well as an electrical drive to complete the system are defining the specific requirements of the test bench. These circumstances also affect the measurements and have to be considered during the evaluation of the results.

36.

R. Wegener, S. Gruber and S. Soter, "Development of a low cost embedded diagnosis system for servo controlled drives including data mining technologies" in 2009 IEEE 18th International Symposium on Industrial Electronics (ISIE), 2009, pp. 373--377.

Abstract:
This paper deals with an embedded diagnosis device which improves the reliability of a machine including servo controlled drives by monitoring the system parameters and detecting abnormalities and creeping changes. The detection algorithm is based on data mining technologies, well known in business administration. The presented system consists of a low cost processor board with an SD-card slot for data storage and a field bus connection and is completely independent of the main machine control. The additional benefits are online monitoring possibilities and the storage of the process variables in a high efficient way during the complete lifetime of the machine.

35.

S. Gruber, C. Junge, F. Senicar and S. Soter, "Optimization of a high force tubular linear drive concept with discrete wound coils to fulfill safety standards in industrial applications" in 2009 IEEE Energy Conversion Congress and Exposition, 2009, pp. 2431--2435.

Abstract:
This paper deals with the next step of development of a tubular permanent magnet linear drive concept for industrial applications up to 3000 N thrust force where low cogging forces are required to fulfill safety standards. The presented linear drive concept is designed for easy production and assembly of a few hundred units per year. It can be manufactured on standard production machines because all ferromagnetic parts are made of standard not-laminated steel. This results in a very economic product. Further more the drive concept includes an internal low cost position sensor based on the hall-effect. The different steps of development are proven by measurements of thrust and cogging forces of different prototypes.

34.

C. Junge, F. Senicar, R. Wegener and S. Soter, "Pressure control of a nonlinear system with a linear-PMSM and a standard inverter" in 2009 IEEE International Electric Machines and Drives Conference, 2009, pp. 83--88.

Abstract:
This paper deals with a high dynamic hydraulic pressure control. The pressure is generated by an inverter driven linear drive which applies a force on a hydraulic cylinder. The linear drive has to generate a pressure profile into the hydraulic system and has to keep it at a constant value after reaching the demanded pressure. The controlled system, containing hydraulic oil, dissolved air and overall three spring packs, is showing a highly non-linear characteristic. The control cascade of the inverter is based on a standard position control loop, which is enhanced by a PI based pressure controller, a dynamically adapted position feed-forward and an active anti-windup of the controller in order to provide optimal control behavior of the nonlinear system.

33.

T. Rösmann and S. Soter, "Regenerative Operation of DC-Series Machines in Pitchsystems for Multimegawatt Windturbines" in 2008 IEEE Industry Applications Society Annual Meeting, 2008, pp. 1--7.

Abstract:
Modern windmills and multimegawatt turbines are nearly exclusively equipped with electrical pitchsystems.The pitchsystem itself has to fulfill the following functions: In the case of strong wind conditions during normal operation, the system is responsible to limit the generator torque. On the other hand, the feathering position of the blades is needed to brake down the turbine in stop or emergency situations. In modern windturbines this aerodynamical brake is necessary, because the mechanical brake is designed as a holding brake and is not able to prevent overspeed conditions. The last function described is safety relevant. Because of this, pitch systems are equipped with an backup energy storage. So the blade can be put into feathering position in any case. DC-machines are preferred in pitch systems because of their capability to be supplied directly by the DC-storage unit without any control or powerelectronics. The motor must be designed especially for this battery driven operation because current and speed during emergency battery drive are depending on the mechatronical behaviour of the machine. Actually two different DC machine types are used in pitch systems: DC-series and DC-compound machines. DC- compound machines were introduced because of their natural 4Q operation area. But an actual development allows the regenerative operation also for DC-series machines and makes them very cost attractive for multimegawatt pitchsystems.

32.

S. Soter, "Wind Converters and Farms -- Technologies and Control", Electrical Energy Systems -- University Enterprise Training Partnership, vol. 2008, no. 4, 2008.

31.

R. Wegener, S. Gruber, K. Nötzold and S. Soter, "Optimization of a Low-Cost Position Sensor for a Permanent Magnet Linear Drive" in PCIM Asia 2008, 2008.