A new dc-dc converter with high voltage gain is proposed in this study. The proposed converter consists of two switches which are turned on and off simultaneously. Additionally, two Switched-Capacitor (SC) cells and one Energy Storage (ES) cell are utilized in the structure of the proposed converter. These result in high voltage gains at low values of the duty cycle. Besides, the voltage stress across the power devices is low and below half of the output voltage. Therefore, the MOSFET switches with low RDS-on and devices with reduced nominal voltage can be used in the proposed converter which in turn reduces the conduction and turn-on losses. The analysis of the voltage and current stresses of the devices is accomplished. The circuit performance is compared with other solutions in the literature in terms of voltage gain and normalized voltage stress of switches and diodes. Eventually, in order to verify the theoretical analysis, the experimental results are provided.

In this paper, a high step-up non-isolated DC-DC converter is proposed to provide high voltage-gain with low voltage-stress on semiconductors. The main feature of the proposed structure is its flexibility in providing constant output voltages with a reasonable range of voltage stress. This flexibility of the voltage-gain is achieved by different combinations of duty cycles. Also, this feature improves the efficiency of the proposed converter. This structure consists of three switches, two inductors, three capacitors and four diodes. In this paper, description of continuous conduction mode (CCM), discontinuous conduction mode (DCM), boundary condition mode (BCM), non-ideal model, and control method are presented. Comparisons between the proposed converter and other related structures show that in this converter, the voltage gain is improved and semiconductors voltage stresses are reduced. In order to verify the mathematical analysis, a 500W laboratory prototype of the proposed converter is built and its experimental results are investigated completely.

This paper aims to propose a new non-isolated step-up multi-port dc-dc converter. The proposed topology is a dual-input dual-output dc-dc converter with different output voltages levels. This makes it possible to be used in hybrid energy systems with different input sources as well as in electric vehicles (EVs) to supply the traction motor and auxiliary loads. The proposed converter is capable of providing high voltage gains with small values of duty cycles and low normalized peak voltage stress (NPVS) across the semiconductor devices. Therefore, the switches with small turn-on resistance and the diodes with a reduced nominal voltage can be used which in turn reduces the switching and conduction losses. The operation principles of the proposed converter are explained and steady-state analysis is carried out. Then, the circuit performance is compared with other related step-up multi-port dc-dc converters in the literature. Eventually, the performance of the proposed converter is validated with experimental results.

To compete with other types of electrical machines as well as other manufacturers, the performance characteristics of axial-flux permanent-magnet (AFPM) machines should be improved. Reduction of the higher harmonic components from the induced back electromotive force is preferred during design process of an electrical machine. To achieve an almost sinusoidal induced phase voltage, a sinusoidal air-gap flux density distribution should be produced. Furthermore, in order to easy startup and also less noisy performance of electrical machines, the cogging torque of the machine should be reduced. In this paper, the surface-mounted AFPM machines equipped with magnets with different outlines are investigated and the machine performances are computed via 3-D finite-element analysis. According to the obtained results, magnets with sinusoidal outline offer better performance characteristics compared with cylindrical and sector-like magnets.