This paper proposes a methodology for shape optimization of the starting cage of a line start permanent magnet synchronous motor motor with the aim to improve its synchronization performance. The parameters of the machine are established from a field-circuit model, where the magnetic field is simulated using a finite element method (FEM). A strategy for evaluating machine parameters exploiting parallel computing is proposed. To facilitate the use of FEM package, bespoke procedures have been developed and model parameterization applied with the aid of the scripting language Visual Basic. A particle swarm algorithm has been adapted for design optimization purposes. The proposed strategy has been verified via test simulations.

Purpose: The purpose of this paper is to elaborate upon the mathematical model of coupled electromagnetic, fluid dynamic and motion phenomena that will allow for investigation of the magnetic hysteresis influence on the axial symmetry magnetorheological fluid (MRF) clutch operation.Design/methodology/approach: To solve the partial differential equations describing magnetic vector and fluid velocity potential distributions in axial symmetry MRF electromechanical transducers the finite‐element methods have been applied. To solve model equations in the time domain, the time stepping method have been adopted. To introduce magnetic hysteresis phenomenon to presented approach the Jiles‐Atherton model have been applied. The physical properties of MRFs have been modeled by means of the Bingham model. Owing to high nonlinearity of the considered problem to solve obtained matrix equations systems the iterative Newton‐Raphson combined with the block over relaxation method have been applied.Findings: The proposed model of coupled phenomena and the elaborated algorithm for solving the nonlinear model equations can be successfully applied in the analysis of transients in the MRF transducers taking fluid dynamics and magnetic hysteresis into account. Comparison of the measured and calculated clutch characteristics proves the model accuracy. Moreover, it has been shown that the residual magnetic flux density of the ferromagnetic core has significant impact on both to yield stresses forming in MRFs as well as the torque in disengagement clutch operation.Originality/value: Development of the method for analysis of transients electromagnetic and fluid flow phenomena in MRF transducers taking magnetic hysteresis, electric circuits and motion into account. The presented approach is universal and can be successfully applied in other types of MRF electromechanical transducers such as clutch, brakes, rotary and linear dampers.

This paper presents the contemporary problems of polymer waste recycling, mainly recycling cables from end-of-life vehicles. The authors developed a new material based on mixed polymer waste (ASR) modified with a ductile polymer, mainly recycled low-density polyethylene (rLDPE), to produce moisture-resistant boards with beneficial mechanical properties. The ASR-based compositions without and with homogenization process—including physical, chemical, and shear-assisted compatibilization—were successfully applied and verified by evaluating final recycled product properties. The results showed that recycled polyethylene (rLDPE) was effective as a modifier increasing tensile modulus and flexural strength compare to an ASR mixture. It was found that the adding 5 wt % of polyethylene-grafted maleic anhydride (PE-g-MAH) as a compatibilizer to the ASR mixture significantly increases the homogenization of the components in the ASR matrix. The optimal solution for management cable waste is the manufacture of ASR composites with homogenization using an internal mixer the adding 20 wt % of rLDPE and 5 wt % of PE-g-MAH to the mixed plastics cable waste. The results obtained demonstrate that the hot-pressing with the pre-blending with rLDPE and compatibilizer of the ASR based waste provides a high gain in mechanical and usage properties, enabling the circular economy of plastics from automotive cables.

This study deals with the impact of squirrel cage design on the synchronisation of the line start permanent magnet synchronous motor (LSPMSM). The numerical model of the machine is based on the finite element method. Special attention is paid to the analysis of the synchronisation process during the start‐up process for high inertia loads. The results for two different designs of squirrel cage are presented and discussed. The strategy for the optimisation of the cage shape of the LSPMSM has been proposed and validated by numerical examples.

The work presented here describes the first results of an effective method of assessing the quality of electrostatic separation of mixtures of polymer materials. The motivation for the research was to find an effective method of mechanical separation of plastic materials and a quick assessment of the effectiveness of the method itself. The proposed method is based on the application of a dedicated vision system developed for needs of research on electrostatic separation. The effectiveness of the elaborated system has been demonstrated by evaluating the quality of the separation of mixtures of poly (methyl methacrylate) (PMMA) and polystyrene (PS). The obtained results show that the developed vision system can be successfully employed in the research on plastic separation, providing a fast and accurate method of assessing the purity and effectiveness of the separation process.

This paper deals with the torque ripple minimization method based on the modulation of the phase currents of the permanent-magnet synchronous motor (PMSM) drive. The shape of the supply current waveforms reducing the torque ripple of the machine considered was determined on the basis of finite element analysis (FEA). In the proposed approach, the machine is supplied by a six-leg inverter in order to allow for the injection of zero sequence current harmonics. Two test PMSMs with fractional-slot concentrated windings (FSCW) and surface-mounted permanent magnets (SPMs) have been examined as a case study problem. Wide-range fractional analyses were performed using developed numerical models of the electromagnetic field distribution in the considered machines. The results obtained show that the level of torque ripple in FSCW PMSMs can be effectively reduced by the modulation of the phase currents under the six-leg inverter supply.