This paper proposes a novel hybrid multilevel converter with DC fault-blocking capability, i.e., the neutral-point clamped hybrid multilevel converter(NHMC).By employing two types of unipolar full-bridge submodules al...This paper proposes a novel hybrid multilevel converter with DC fault-blocking capability, i.e., the neutral-point clamped hybrid multilevel converter(NHMC).By employing two types of unipolar full-bridge submodules along with director switches, which are composed of seriesconnected insulated-gate bipolar transistors, the NHMC combines the features and advantages of the neutral-point clamped converter and the modular multilevel converter.The basic topology, operating principles, modulation scheme, and energy-balancing scheme of the NHMC are presented. The DC fault-blocking capability of the NHMC is investigated. The number of power electronic devices used by the NHMC is calculated and compared with other multilevel converters, showing that the proposed NHMC can be an economical and feasible option for medium-voltage DC transmission with overhead lines. Simulation results demonstrate the features and operating scheme of the proposed NHMC.展开更多
In this paper, we present the combination of drain field plate （FP） and Schottky drain to improve the reverse blocking capability, and investigate the reverse blocking enhancement of drain FP in Schottky-drain AlGaN...In this paper, we present the combination of drain field plate （FP） and Schottky drain to improve the reverse blocking capability, and investigate the reverse blocking enhancement of drain FP in Schottky-drain AlGaN/GaN high-electron mobility transistors （HEMTs）. Drain FP and gate FP were employed in a two-dimensional simulation to improve the reverse blocking voltage （VRB） and the forward blocking voltage （VFB）. The drain-FP length, the gate-FP length and the passivation layer thickness were optimized. VRB and VFB were improved from -67 V and 134 V to -653 V and 868 V respectively after optimization. Simulation results suggest that the combination of drain FP and Schottky drain can enhance the reverse blocking capability significantly.展开更多
A novel 4 μm thickness drift region lateral insulated gate bipolar transistor with a floating n-region （NR- LIGBT） in p-substrate is proposed. Due to the field modulation from the n-region, the vertical blocking ca...A novel 4 μm thickness drift region lateral insulated gate bipolar transistor with a floating n-region （NR- LIGBT） in p-substrate is proposed. Due to the field modulation from the n-region, the vertical blocking capability is enhanced and the breakdown voltage is improved significantly. Low area cost, high current capability and short turn-off time are achieved because of the high average electric field per micron. Simulation results show that the blocking capability of the new LIGBT increases by about 58% when compared with the conventional LIGBT （C-LIGBT） for the same 100 μm drift region length. Furthermore, the turn-off time is shorter than that of the conventional LIGBT for nearly same blocking capability.展开更多
基金supported by Key Science and Technology Project of China Southern Power Grid(Research on Key Technologies and Demonstration Application of Flexible Coordinated Control of Electromagnetic Loop Network in Metropolitan Power Grid with High Load Density,No.GZHKJ00000101)
文摘This paper proposes a novel hybrid multilevel converter with DC fault-blocking capability, i.e., the neutral-point clamped hybrid multilevel converter(NHMC).By employing two types of unipolar full-bridge submodules along with director switches, which are composed of seriesconnected insulated-gate bipolar transistors, the NHMC combines the features and advantages of the neutral-point clamped converter and the modular multilevel converter.The basic topology, operating principles, modulation scheme, and energy-balancing scheme of the NHMC are presented. The DC fault-blocking capability of the NHMC is investigated. The number of power electronic devices used by the NHMC is calculated and compared with other multilevel converters, showing that the proposed NHMC can be an economical and feasible option for medium-voltage DC transmission with overhead lines. Simulation results demonstrate the features and operating scheme of the proposed NHMC.
基金supported by the National Natural Science Foundation of China(Grant Nos.61334002 and 61106106)the Opening Project of Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory,China(Grant No.ZHD201206)
文摘In this paper, we present the combination of drain field plate （FP） and Schottky drain to improve the reverse blocking capability, and investigate the reverse blocking enhancement of drain FP in Schottky-drain AlGaN/GaN high-electron mobility transistors （HEMTs）. Drain FP and gate FP were employed in a two-dimensional simulation to improve the reverse blocking voltage （VRB） and the forward blocking voltage （VFB）. The drain-FP length, the gate-FP length and the passivation layer thickness were optimized. VRB and VFB were improved from -67 V and 134 V to -653 V and 868 V respectively after optimization. Simulation results suggest that the combination of drain FP and Schottky drain can enhance the reverse blocking capability significantly.
基金supported by the National Natural Science Foundation of China(No.61076082)
文摘A novel 4 μm thickness drift region lateral insulated gate bipolar transistor with a floating n-region （NR- LIGBT） in p-substrate is proposed. Due to the field modulation from the n-region, the vertical blocking capability is enhanced and the breakdown voltage is improved significantly. Low area cost, high current capability and short turn-off time are achieved because of the high average electric field per micron. Simulation results show that the blocking capability of the new LIGBT increases by about 58% when compared with the conventional LIGBT （C-LIGBT） for the same 100 μm drift region length. Furthermore, the turn-off time is shorter than that of the conventional LIGBT for nearly same blocking capability.
