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The paper describes two main approaches of periodic control under variable frequency conditions: frequency adaptive multioscillatory control (FAMOSC) and fractional delay repetitive control (FDRC). The methods are applied in the control system of a grid-tie converter to increase the quality of phase currents in case of distorted grid voltages. The paper compares structures, performance and implementation of FAMOSC, FDRC and the conventional approach of repetitive and multioscillatory control. Performances of the control systems are illustrated with experiments on a laboratory test bench. The article describes tuning process of FDRC and FAMOSC with the usage of Particle Swarm Optimization algorithm. A detailed analyse and research of the techniques in terms of computational complexity is presented. Practical hints for implementation and resource optimization of both techniques on DSP are included. For FAMOSC a fast implementation of prewarping is proposed.

One of the main problems of switched reluctance motor are torque ripple, vibrations and high acoustic noise which decrease user comfort and cause faster machine and drive system wear out. In this paper a new approach for torque ripple minimization is presented, which is based on modified multi-oscillatory controller.

This paper aims to analyze process of Variable Reluctance Generator stator core radial vibrations development. Frequency structure of generated vibrations strongly depends on rotor speed, generator load and adopted technique of phase current limitations. Qualitative change of vibration frequency structure could be associated with particular state of operation of mechanically coupled system (generator and turbine). Significant increase of rotor angular velocity variations associated with rotating mass (coupled rotors) free oscillations is correlated with maximum amplitude of developed vibrations acceleration. Interesting phenomenon is appearance of vibrations that present chaotic behavior.

Vibrations of high speed SRM design focused on possible highest efficiency and low torque ripples both in motoring and generating mode of operation are investigated. The main constructional nodes that are source of vibrations are identified based on comparison of time sequences of motor frame displacement acceleration with total and phase motor current. Vibration analysis is the second stage of design process that suggest possible additional changes in stator and rotor geometry and controller operation that minimizes detrimental vibro-acoustic phenomenon.

The results of four phase switched reluctance motor tests were presented in this paper. Torque versus speed characteristics were executed for different control parameters. The energy converter designed to this motor allows to control phase current and switching angles independently. The experimental results show that the shape of the mechanical characteristics heavily depends of the switching angles and maximum phase current. It has been found through tests, that efficiency characteristics of the drive can be improved by the right adjustment of the switching angles, even in the low load conditions.