Joachim Böcker

Learn More
A problem encountered with electrically driven vehicles are resonances in the drive train caused by elasticity and gear play. Disadvantageous effects caused by this are noticeable vibrations and highmechanical stresses due to torque oscillations. The oscillations can be damped using a control structure consisting of a nonlinear observer to estimate the(More)
The switching frequency of an inverter under direct torque control is mainly decided by the fluxand torque-controller output switching counts. It is known that, with fixed hysteresis bands, the switching frequency varies as the operating point changes. It is possible, however, to keep the switching frequency constant by the adaptation of hysteresis bands.(More)
A test track of 530 m length for linear motor driven railway vehicles in scale of 1:2.5 was built at the University of Paderborn in 2002. A doubly-fed long stator linear motor does not only drive the vehicles, but offers the opportunity of a contactless energy transmission into the vehicle’s on-board supply system, too. In this pape, the motion control(More)
Molecular Dynamics (MD) computer simulation studies are reported for a system consisting of two model membranes in contact with an aqueous solution. The influence of the membrane on the adjacent liquid is of main interest in the present study. It is therefore attempted to make the system sufficiently large to encompass the entire region between bulk liquid(More)
We present a new concept for online multiobjective optimization and its application to the optimization of the operating point assignment for a doubly-fed linear motor. This problem leads to a time-dependent multiobjective optimization problem. In contrast to classical optimization where the aim is to find the (global) minimum of a single function, we want(More)
This paper presents a 1MW, 12-pulse thyristor rectifier with passive filter and DSTATCOM for low voltage, high current industrial dc loads. The considered process act (electrically) as a current controlled, variable voltage load. Moreover the load characteristic varies extensively with number of hours of operation. Variable compensation capabilities are(More)
An energy supply system based on a hybrid energy storage unit combined of batteries and ultracapacitors for a railway vehicle is studied. In order to optimize the energy supply system architecture and to manage the energy distribution the power electronic converters connecting ultracapacitors, batteries and the DC-link are investigated together with control(More)
Model predictive control (MPC) offers a variety of advantages compared to conventional control methods. The problem with MPCs is the high computational cost and the associated long control cycle time. This makes the use of MPCs unattractive for processes with small time constants, as in permanent magnet synchronous motors with interior magnets (IPMSM) for(More)