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This article seeks to present the simple and easy to manufacture design of a permanent magnet generator based on coreless windings. An example is shown of basic calculations based on an equivalent magnetic circuit. Finally, a description of a 20 kW prototype of PMSG is presented based on rectangular magnets which contains mechanical design and experimental results.

The analysis presents flux dependence using several parameters such as: magnet's grade and size in comparison with coil and air‐gap dimensions. The second part of the article concentrates on simulation results of Finite Element Method analysis (FEM) that clearly shows the flux distribution for different magnet shapes – trapezoidal and rectangular.

The presented topology of the machine has several advantages, e.g. there is no starting and cogging torque which is very important especially for wind power systems because of the start up point of the turbine. Moreover, it is cheap and easy to manufacture because of ironless technology in stator. The generator can be produced in the range of single watts up to hundreds of kilo watts of power in multi disk operation.

The ironless technology applied to the stator, results in the need for using stronger magnets in comparison with a classic iron‐core permanent magnet machine.

This axial‐flux machine seems to be very interesting for low speed power generation systems such as wind and water turbines. Cost effective permanent magnet generator can be used for local power generation (e.g. heating). The generator can also be connected to the main grid through a special grid‐tie‐inverter.

The article presents the simple and rarely presented topology and describes a few methods of optimisation of the parameters to achieve maximum power.

This paper presents control strategy of VSC connected to the unbalanced grid in stationary coordinates system. The algorithm shown in the paper can be applied to typical inverter to reduce or even eliminate oscillation of DC‐link voltage under unbalanced operation. That has a direct influence on constant flow of p component of power which is essential for drives system for reducing torque ripples.

The presented strategy of control assumes that orientation of grid voltage and line current vectors hodographs have to be opposite. Mathematical analysis and simulation has been done. Laboratory tests on low power has also been carried out.

This method leads to fixed p component of power flow and fixed DC bus voltage. The presented idea of control may cause reduction of voltages asymmetry in three‐phase network with significant impedance (local grid, microgrid, isolated grid).

For 50 Hz power system, the presented control strategy has at least 5 ms response time because calculations are based on current and 5 ms delayed values of grid voltage. The paper presents only a simple steady state laboratory test that has been done in low scale of voltage and current.

The paper shows an example of implementation of the method with simple dead‐beat current controller based on DSP microprocessor. The algorithm can be easy applied in a DC/AC converter for elimination DC‐link oscillations under unbalanced working conditions.

Control methods presented in many other papers always provide sinusoidal, symmetrical three‐phase currents irrespective of grid voltage symmetry. The presented idea of control causes reduction of DC‐Link voltage and p, q components of power oscillations due to grid voltage asymmetry.