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The global energy crisis has raised environmental concerns, leading governments to invest in renewable energy and address electric vehicle (EV) and hybrid EV (HEV) difficulties. One of the main challenges is the interface between the energy storage system and the DC-link of the three-phase inverter. For this aim, an improved voltage gain bidirectional DC/DC converter based on a voltage multiplier cell (VMC) is proposed in this paper, which acts like a high boost converter when the energy storage system is powering the EV and a buck converter when regenerative braking is required. The proposed bidirectional converter has advantages like low device account, simple structure, reduced switching power losses, high voltage gain, common ground, and increased efficiency. An output voltage of 10 times the input voltage in boost mode is provided by the proposed converter. Also, the proposed converter can generate a voltage 0.26 times lower than the input voltage in buck mode. The operating principle and comparative analysis with other existing converters are presented. Moreover, the efficiency calculation is discussed by assuming the non-ideal parameters. The proposed converter has a maximum efficiency of 97.78%. Finally, a 500 W simulation prototype is implemented in PSIM software to confirm the theoretical analysis. [ABSTRACT FROM AUTHOR]

This paper proposes a new design for line-start operation of synchronous reluctance motors. In the past years, synchronous reluctance motors have been studied by many researchers. Due to high efficiency, they have gained increasing interest because in the synchronous operation, there is limited losses in the rotor. On the other hand, line-start operation of the synchronous reluctance motors is an important challenge that can make this type of the motors popular in many applications. However, line-start operation techniques should not considerably affect the steady-state characteristics of the motor. In the proposed design, the arrangement, size and shape of the rotor conductor bars are designed based on the rotor magnetic circuit difference between induction and reluctance synchronous motors. Complete assessment of the motor parameters are examined using finite element analysis. The proposed structure improves the starting characteristics of the motor. Moreover, power factor of the proposed motor is slightly increased in comparison to that of conventional line-start synchronous reluctance motors. The results obviously show effectiveness of the proposed line-start operation strategy for the synchronous reluctance motors. Finally, experimental verification are also included to confirm the finite element analysis results. [ABSTRACT FROM AUTHOR]

To meet the higher DC link voltage requirement in distributed energy resources (DERs) such as fuel cells (FCs), wind turbines (WTs), and photovoltaic (PV) systems, DC–DC converters are applied. A voltage‐lift (VL) circuit‐based transformer‐less active switched LC‐network (ASLC) converter with a high‐voltage gain is proposed in this paper. Compared to a similar reference converter, the voltage gain of the proposed converter increases efficiently by adding one extra capacitor and diode. The operation of the converter in continuous current mode (CCM) and discontinuous current mode (DCM), the analysis of the steady‐state condition, and comparative analysis with some similar converters are discussed. Moreover, the parasitic elements are assumed to calculate the DC‐voltage gain and the efficiency of the converter accurately. The performance of the proposed step‐up converter is simulated in the PSIM software. A prototype circuit rating of about 20/280 V, 200 W of converter model is designed, and its performance is validated. The experimental outcomes clarify the feasibility of the proposed converter. [ABSTRACT FROM AUTHOR]