This paper presents the results of simulation tests of a unique hybrid-excited permanent magnet machine operating in in different working regimes. The common feature of analyzed machine is a presence of magnetic barriers in the rotor structure. Structurally, this machine combines the advantages of the PMa-SynRM machine (Permanent Magnet-assisted Synchronous Machine) and a wound synchronous machine. The paper presents, among other results, the voltage and torque characteristics as a function of the current in the stator and the additional DC control coil. Selected results of experimental studies are also shown.

The paper presents 3D-FEA results of electromagnetic torque characteristics of a Field Control Axial Flux Permanent Magnet Machine (FCAFPMM) obtained for different pole shapes. The influence of the angular span of iron and permanent magnet poles on the cogging torque performance has been analysed at different excitations of an additional stator winding.

Purpose This paper aims to present the project of a permanent magnet synchronous machine which can be used as generator in the vertical axis wind turbine. Design/methodology/approach In the study, finite element analysis was used to perform simulation research of electrical machines. Based on the simulation studies, an experimental model was built. The paper presents also selected experimental results. Findings During the research, it was found that the radial arrangement of the permanent magnets is more favorable than the tangential one for the selected structure of the generator with permanent magnets. Research limitations/implications During the experimental research, a problem was encountered involving the correct control of the constructed generator at low rotational speeds. Practical implications The proposed solution can be used in low-speed vertical axis wind turbines. Social implications The presented research fits the global trend toward the use of alternative and renewable energy sources. Originality/value The paper presents new simulation studies of two low-speed generator topologies. The results for the radial and tangential arrangement of the permanent magnets in the rotor were verified. Based on this research, an experimental prototype of a generator for a slow-speed vertical axis wind turbine was built.

This paper presents the design and research results of a claw pole machine with hybrid excitation. This machine is excited by permanent magnets and an electromagnetic coil. Both excitation sources are located in the rotor of the machine. Additionally, the rotor is made of a laminated core. This approach facilitates the process of its construction and enables the implementation of even very complicated structure of the rotor, which would be difficult in case of making the rotor from a one piece of material. This paper presents the construction as well as the results of simulation and experimental tests of the machine prototype. The tests showed that the proposed machine has the ability to adjust the voltage in a wide range. Such as a feature could be used, for example, to increase the speed of motor operation in case of an electric vehicle application, but also to regulate the voltage in wind turbines which generators operate at varying rotor speeds resulting from changing wind speed.

The paper presents results of simulation tests of a hybrid excited permanent magnet machine operating in various states. The common feature of this machine is the presence of magnetic barriers in the rotor structure. Structurally, this machine combines the advantages of the PMa-SynRM machine (Permanent Magnet assisted Synchronous Machine) and a wound synchronous machine. The paper presents the voltage and torque characteristics for different values of the current in the stator and the DC control coil. Selected results of experimental studies are also shown.