Nowadays, multi-winding transformers are widely used in power systems, especially in traction networks and steel producing companies. The multi-winding transformers have special geometry. They encounter with serious problems and difficulties in design procedure in comparison with conventional two-winding transformers. Considering the importance of windings losses (and the generated heat), the current research firstly focuses on thermal calculations in this type of transformers, also introduces a semi-numerical technique for electromagnetic analysis of split-winding traction system transformer. Combining finite element and analytical methods, the windings losses distribution due to eddy currents is calculated and the modeling results are validated using the experimental results. As shown, the introduced semi-numerical method is a powerful technique for electromagnetic modeling and winding losses calculations in split-winding transformers. Also, the winding losses of the split-winding transformer are discussed and compared to the conventional two-winding transformer results. Finally, the relation between the winding losses and frequency is studied in this paper.

Plastic hinge properties play a crucial role in predicting the nonlinear response of structural elements. The plastic hinge region of reinforced concrete normal beams has been previously studied experimentally and analytically. The main objective of this research is to evaluate the behavior of the plastic hinge region of reinforced concrete deep beams and its comparison with normal beams through finite element simulation. To do so, ten beams contain six deep beams, and four normal beams, under concentrated and uniformly Distributed loading, are investigated. Lengths in the plastic hinge region involving curvature localization, rebar yielding, and concrete crushing zones are studied. The results indicate that the curvature localization zone is not suitable for the prediction of plastic hinge length in reinforced concrete deep beams. Based on the results it can be stated that in simply supported normal beams the concrete crushing zone is focused on the middle span, but in simply supported deep beams by creating a compression strut between loading place and support, the concrete crushing zone spreads along the compression trajectory. The rebar yielding zone of simply supported beams increases as the loading type is changed from the concentrated load at the middle to the uniformly Distributed load.

The aim of this research is to design a controlling loop that eliminates the irregularities in yarn tension during the winding process. In order to achieve this, we employed a relative feedback industrial control system. The yarn tension sensor measures the tension. Its output is analyzed in the automatic controlling unit. This unit adjusts the tension level according to feedback signals, thus adjusting the yarn tension to the desired value. The yarn package wound using this system will additionally experience the least yarn tension variations.

Stator fault detection may be done with different methods. However, If the stator current sensor is to be installed for protection and controlling of an induction motor, signature and FFT analyses are the mostly used for on-line stator fault detection. Also, winding function method is an effective procedure for modeling motors in unbalance conditions. Simulation results with this method are used in this paper for detection of the turn-to-turn, coil-to-coil and phase-to-phase faults. The FFT analysis of line current, interrupting motor power supply; negative sequence currents and R.M.S value of speed are all important criteria for fault diagnosis. Simulation and Experimental results confirm that the FFT analyses and interruption of motor from supply and R.M.S value of the speed are the effective methods for the fault detection. Experimental results are presented to verify the accuracy of the simulation results

In this paper, a new topology of fractional slot concentrated winding double rotor axial flux permanent magnet synchronous motor (FSCW-DRAFPMSM) is introduced. The desired structure consists of a nonslotted stator core and two rotor discs. The pole number of the two rotors is different and these two rotors rotate at different speeds in opposite directions. A sample motor with an output power of 200 Watts is designed with the proposed structure. The two rotors of this sample motor rotate with speeds of 1200 and 857 rpm. The Finite Element Method (FEM) is employed to evaluate the performance of the proposed structure. Some performance characteristics of the case study machine, such as the Back EMF, input power, and electromagnetic torques of two rotors are presented to confirm the correctness of the operation of the proposed structure. In addition, the shifting technique is used to improve the Back EMF waveform of the machine. An analytical formula is proposed for calculating the fundamental component of the Back EMF waveform. The accuracy of the formula is approved by FEM.