The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The following paper presents new fault tolerant converter topology for switched reluctance machines, that features multilevel output along with its advantages. The principle of operation in normal as well as in the fault conditions are described. Previously proposed modulation strategy including DC bus voltage balancing scheme is applied and tested in measurements. Low cost, discrete implementation...
This publication describes an novel fault tolerant converter for switch reluctance machines. It is proposed to take the advantages of multilevel output converter in the normal operation mode and exploit the switching states that are destructive for the conventional NPC topology and use them for fault tolerance. Moreover, simple and yet effective modulation technique has been found, modified and improved...
A new control concept for inverter systems in wind turbines is proposed. Thereby only as many parallel connected inverter units as needed are activated to feed in the momentary generated power into the grid. Each inverter unit is equipped with an individual controller without additional communication between the inverter units. The load dependent activation and deactivation of inverter units is controlled...
A control strategy for HVDC converters in future wide-area multi-terminal HVDC grids is developed. The control strategy is inspired by the dynamic behaviour of common motor-generator-sets used for electromechanical AC-DC conversion in the medium power range. With the new control strategy HVDC converters are on the one hand suitable for distributed control of DC voltage and they also contribute to...
The following publication describes the method used to calculate current waveforms optimized for minimum RMS value of the current and at the same time ripple-free output torque of the transverse flux reluctance machine. Due to the similarities with switched reluctance machines it is also applicable for this type of electric motors. The method described here, requires detailed characteristics of the...
Power generation using renewable resources is replacing conventional generation using steam power plants all over the world. Therefore a new control concept is shown, enabling a wind power station to behave just as like the synchronous generator in a steam power plant providing ancillary services. The main focus is on the provision of instantaneous and primary reserve and the ability to dampen grid...
The ‘Dual’ high voltage direct current (HVDC) transmission system is a new concept for the grid connection of large or several nearby-located offshore wind farms. The Dual HVDC system consists of one line-commutated converter (LCC) and one auxiliary self-commutated voltage source inverter (VSI) at both ends of a point-to-point DC transmission line. The paper begins with an introduction into the operating...
With a new control concept presented in this paper, wind power stations with inverter-coupled synchronous generators (SG-WPS) behave to a great extent like the turbine-generator sets of conventional thermal power plants including the ability of the release of active- and reactive reserve power. This allows every single SG-WPS to improve its contribution to power grid stability. The new control concept...
Wind turbines represent elastically coupled multi-mass systems. Dynamic load changes caused by a gust of wind lead to peaks in the shaft torsion torque and result into high stress for the system. This paper presents an opportunity to integrate a stress minimizing control strategy, which was presented in [7], on wind turbines with doubly fed induction generator (DFIG). To avoid extensive measurements...
Elastically coupled multi-mass systems are a part of many industrial applications, like wind energy plants or drive trains in general. Dynamic load changes often cause peaks in the shaft torsion torque and jerk, resulting in damages to the system. A control strategy to reduce and / or limit this stress was presented in [9], but needed difficult to implement and expensive measurements of the shaft...
Integration of wind power stations in primary control of the grid can be necessary in future. One solution to solve this problem is the emulation of a turbine and a generator such as in conventional power plants. The model is split into two parts: The grid-side inverter is controlled by a model of a separately excited synchronous machine with amortisseur in combination with torque and excitation voltage...
Design of multi-turns concentric saddle windings are required for flux concentrated permanent magnet transverse flux machine, FCPM-TFM in a sector wise configuration. In the segmented construction of FCPM-TFM, saddle coils or concentric type of windings are used to replace the ring coils, which are normally utilised in the conventional layered-phase structures for generating fields' perpendicular...
Flux concentrated permanent magnet transverse flux machine (FCPM-TFM) that is designed to achieve a compact design for in-wheel applications, has been set under test experiments to verify the published investigations that are demonstrated in [1-6] and achieved through many computer simulations via using FLUX3D, a 3D finite element (FE-) package from Cedrat. The study in this paper includes generator...
The magnetic field in flux concentrated permanent magnet transverse flux machines; FCPM-TFM is of a three dimensional, 3D pattern. This will initiate the occurrence of eddy currents in the parts of conducting materials of the stator, rotor, coil conductors and in the PMs as well, where magnetic fields exist in perpendicular direction to their planes, causing an apparent reduction in the efficiency...
Transient finite element analysis of a flux concentrated permanent magnet transverse flux machine (FCPM-TFM) that is designed to be incorporated as in-wheel motor for a mobile platform using FLUX3D, a 3D-finite element (FE-) package from Cedrat with external circuit connections and electromechanical coupling features, is presented in this paper. Two magneto-dynamic studies of transient analysis are...
In direct drive applications TFM have been proposed as a powerful alternative. A working TFG and an appropriate power converter were developed. Transient simulation of the system with relevant disturbance influences is done efficiently. A current control is used to optimize power-feedback into the grid. Measurements show positive results.
Elastically coupled multi-mass systems are found in many industrial applications, like wind energy plants or in robotics. Dynamic load changes often cause peaks in the shaft torsion torque and result in damages to the system. This paper presents a control strategy to reduce the dynamic loads on the drive train and the stress in wind turbines and other multi-mass systems, by directly controlling and...
Tranverse flux machines (TFM) have been proposed as a powerful direct drive alternative. The construction and control of TFM have often proved a problem. In this paper the construction of a working transverse flux generator is presented. Its characteristics are predicted by a detailed FE simulation. Also a current control is designed that compensates unsymmetries and maximizes the power output. Measurements...
Controlling a multi-mass system is a common problem in industrial automation. Varying or even unknown parameters cause the difficulty of the control. A powerful tool in order to control systems with uncertain parameters is a robust Hinfin-control. Unfortunately the complex structure and the mathematical theory prevent known Hinfin controllers from the usage in many industrial applications. In this...
Controlling a multi-mass system is a common problem in industrial automation. Varying or even unknown parameters cause the difficulty of the control. A powerful tool in order to control systems with uncertain parameters is a robust H∞-control. Unfortunately the complex structure and the mathematical theory prevent known H∞ controllers from the usage in many industrial applications. In this work the...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.