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The simulations and experiments for two 400 W low‐speed direct‐drive permanent magnet synchronous generators (PMSGs) installed in a Floating Kuroshio Turbine (FKT) were implemented. The towing tank experiments were carried out at National Taiwan University. A generator can start to harvest current energy at the rotation speed of 30 rpm (corresponding to the current flow rate of 0.36 m/s), and produce the rated power of 400 W at 150 rpm. The speed is very low compared with the published reports. The energy conversion efficiency of the FKT is up to 0.85. The results show that the generated direct current (DC) power is more than 800 W at a flow rate of 1.5 m/s. The power coefficient for the FKT is about 0.4. The energy loss at each stage and the power difference between the testing platform and the towing tank experiment were also analyzed. Moreover, the shape of the FKT is a new design. Compared with other structures, the proposed FKT can easily follow the direction of the ocean current and the depth of the FKT can be adjustable; when it doesn't operate, it will float on the surface so that it is easy for maintenance. [ABSTRACT FROM AUTHOR]

This work demonstrates a trench isolated lateral double-implanted MOSFET (LDMOS) on Si-face in 4H-silicon carbide (SiC). A device $\vphantom {_{\int _{}}}$ where ${L}_{\textit {ch}} = 0.8\,\,\mu \text{m}$ and ${L}_{d} = 12\,\,\mu \text{m}$ shows an ${R}_{ \mathrm{\scriptscriptstyle ON},\text {sp}}$ of 22.9 $\text{m}\Omega $ cm2 at a ${V}_{\text {GS}}$ of 20 V and a breakdown voltage (BV) of 1100 V, corresponding to a high BV2/ ${R}_{ \mathrm{\scriptscriptstyle ON},\text {sp}}$ of 55.5 MW/cm2. Devices that have different ${L}_{\text {ch}}$ , ${L}_{\text {JFET}}$ , ${L}_{d}$ , and P-top dose values are measured in order to investigate the effects of geometry on the static performance. Operations at 150 °C are measured to evaluate the temperature performance. Gate charge waveforms are also measured in order to include the switching performance in the evaluation. The ${R}_{ \mathrm{\scriptscriptstyle ON}} \times {Q}_{G}$ and ${R}_{ \mathrm{\scriptscriptstyle ON}} \times {Q}_{\text {GD}}$ values are calculated as 17.7 and $9.0~\Omega $ nC, respectively, which are promising for power-integrated circuit applications. [ABSTRACT FROM AUTHOR]