Phase-Shifted Full-Bridge DC–DC Converter With High Efficiency and High Power Density Using Center-Tapped Clamp Circuit for Battery Charging in Electric Vehicles

Multiphase machines have some distinct merits, including the high power density, high torque density, high efficiency and low torque ripple, etc. which can be beneficial for many industrial applications. This paper presents four different types of six-phase outer-rotor permanent-magnet (PM) brushless machines for electric vehicles (EVs), which include the inserted PM (IPM) type, surface PM (SPM) type, PM flux-switching (PMFS) type, and PM vernier (PMV) type. First, the design criteria and operation principle are compared and discussed. Then, their key characteristics are addressed and analyzed by using the finite element method (FEM). The results show that the PMV type is quite suitable for the direct-drive application for EVs with its high torque density and efficiency. Also, the IPM type is suitable for the indirect-drive application for EVs with its high power density and efficiency.

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High Efficiency and High Power Density Interleaved DC-DC Converter for Electric Vehicles

2019 22nd International Conference on Electrical Machines and Systems (ICEMS) ◽

10.1109/icems.2019.8922149 ◽

2019 ◽

Author(s):

Zimo Yuan ◽

Jinxin Wang ◽

Xue Yuan ◽

Qianfan Zhang

Keyword(s):

Power Density ◽

Electric Vehicles ◽

High Power ◽

High Efficiency ◽

High Power Density

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Near-field thermophotovoltaics for efficient heat to electricity conversion at high power density

Nature Communications ◽

10.1038/s41467-021-24587-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Rohith Mittapally ◽

Byungjun Lee ◽

Linxiao Zhu ◽

Amin Reihani ◽

Ju Won Lim ◽

...

Keyword(s):

Power Density ◽

High Power ◽

High Efficiency ◽

Near Field ◽

Electrical Power ◽

Photovoltaic Cells ◽

High Power Density ◽

Pv Cell ◽

Electrical Power Output ◽

Power Densities

AbstractThermophotovoltaic approaches that take advantage of near-field evanescent modes are being actively explored due to their potential for high-power density and high-efficiency energy conversion. However, progress towards functional near-field thermophotovoltaic devices has been limited by challenges in creating thermally robust planar emitters and photovoltaic cells designed for near-field thermal radiation. Here, we demonstrate record power densities of ~5 kW/m2 at an efficiency of 6.8%, where the efficiency of the system is defined as the ratio of the electrical power output of the PV cell to the radiative heat transfer from the emitter to the PV cell. This was accomplished by developing novel emitter devices that can sustain temperatures as high as 1270 K and positioning them into the near-field (<100 nm) of custom-fabricated InGaAs-based thin film photovoltaic cells. In addition to demonstrating efficient heat-to-electricity conversion at high power density, we report the performance of thermophotovoltaic devices across a range of emitter temperatures (~800 K–1270 K) and gap sizes (70 nm–7 µm). The methods and insights achieved in this work represent a critical step towards understanding the fundamental principles of harvesting thermal energy in the near-field.

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