Rüdiger Appunn

Electromagnetic Guiding of Vertical Transportation Vehicles: Experimental Evaluation

This paper describes the design of an electromagnetic elevator guiding system. One challenge of this design is the overdetermination of the mechanical system due to its high number of adjustment variables. Force decoupling, transformation from local to global quantities, and simulation results of the entire system are presented. In contrast to former works, a new elevator test bench for the evaluation of the simulation results is introduced. Measurement results validate the design process of both the electromagnetic actuators and feedback control.

Electromagnetic guiding of vertical transportation vehicles: state control of an over-determined system

This paper describes the design of a state controller for an electromagnetic elevator guiding system. One challenge of this design is the over-determination of the mechanical system due to its high number of adjustment variables. Force decoupling, the transformation of local and global quantities, and simulation results of the entire system are presented in this paper.

Development of a small scale magnetically levitated train as demonstrator for undergraduate mechatronics students

At the Institute of Electrical Machines of the RWTH Aachen University, there is a project financed by student fees for the realization of a magnetically levitated train in the scale of 1:50. Undergraduate students are supposed to get the possibility to design and build up a real train which serves as demonstrator for a mechatronic system. This projects strengthens the motivation of students, since a practical demonstration of electromagnetic forces is given in addition to theoretical courses. This paper introduces the major project steps and explains the learning targets for the students. It focuses on analytical magnetic circuit design, numerical field simulation, modeling and control of a multi degree of freedom system, electronic circuit design measurement setups and a first prototype test bench.

Simulation of a high voltage system in a hybrid electrical vehicle

In modern hybrid electrical vehicles (HEV) the electrical system includes different voltage levels. Visualization of the electric quantities such as currents and voltages of a high voltage system under load conditions is presented in this paper. Different strategies of electric component modeling such as machines or power electronics are used for an intensive analysis of the electrical system. Evaluation of the DC-link with respect to transients and feedbacks resulting from operational performance or fault operation is done.

Improved rotor pole geometry of a PMSM for wind turbine applications with multiple high-speed generators

Wind turbines (WTs) are energy conversion systems with a very complex electromechanical structure, consisting of highly interconnected subsystems, which are constantly exposed to dynamic electrical and mechanical stress. In order to improve their technical and economic efficiency, new alternative drive train concepts are being sought. This paper proposes a WT drive train with multiple high-speed generators. Different electrical machines are investigated analytically and the permanent magnet synchronous machine with V-shaped internal magnets (VI-PMSM) is chosen as the most suited topology for this application. A simple MATLAB Simulink model is developed to validate the proposed WT configuration in terms of efficiency gain. Furthermore, the operational behavior of the VI-PMSM is improved by means of sinusoidal rotor field poles.

Design of a Contactless Power Supply for Magnetically Levitated Elevator Systems Integrated into the Guide Rail

A contactless energy transmission system is essential to supply onboard systems of magnetically levitated vehicles without physical contact to the guide rail. This paper introduces a contactless power supply (CPS) where the primary is integrated into the guide rail of an electromagnetic guiding system (MGS). The secondary is mounted onboard the elevator car. The advantages of this system when compared to existing energy transmission systems are the low requirement of construction space and reduced costs.

Contactless power supply for magnetically levitated elevator systems using a SMC hybrid actuator

A contactless power supply (CPS) for the cabin of a magnetically levitated elevator is presented in this paper. In contrast to commercial stand-alone contactless power supply systems, a combined CPS and electromagnetic guiding system (MGS) is introduced. The inductive energy transmission is realized by utilizing the magnetic circuit of an actuator of the linear guiding. With this approach two devices are combined into one unit. The hybrid actuator consists of an omega shaped yoke, fabricated of soft magnetic composites (SMC), with permanent magnets and coils on its lateral arms. A concentrated primary winding is added to the guide rail and a coil wound around the central arm of the omega actuator functions as secondary winding. Hereby a superposition of the MGS flux and the CPS flux emerges in the magnetic circuit of the actuator and the transmission path is established. The proposed system requires less construction space and weight when compared to existing energy transmission systems.

A study of a novel wind turbine concept with power split gearbox

This paper focuses on the design and control of a new concept for wind turbines with a planetary gearbox to realize a power split. This concept, where the generated wind power is split into two parts, is to increase the utilization of the wind power and may be particularly suitable for large scale off-shore wind turbines. In order to reduce the cost of the power electronic devices, a synchronous generator, which is driven by the ring gear, is directly connected to the power grid without electronic converter. A servo drive, which functions as the control actuator is connected to the power grid by a power electronic converter. The speed of the main shaft is controlled to track the optimal tip speed ratio. Meanwhile the speed of the synchronous generator is controlled to stay at the synchronous speed. The minimum rated power of the servo motor, which is also the rated power of the converter, is studied and discussed in this paper. The controller for optimal tip speed ratio and synchronous speed tracking is given.