Bulk Power HVDC transmission schemes over distances of up to 2000 km are currently under planning for various large hydropower stations in India and China. Ultra high dc voltage (UHVDC) up to 800 kV is the preferred dc voltage level for these applications. Currently world-wide existing HVDC schemes are limited to maximum voltage levels of 500 kV to 600 kV. Therefore, the impact of increased ste...

A unified multi-stage power-CMOS-transmission-gate-based quasi-switched-capacitor (QSC) DC-DC converter is proposed to integrate both step-down and step-up modes all in one circuit configuration for low-power applications. In this paper, by using power CMOS transmission gate as a bi-directional switch, the various topologies for step-down and step-up modes can be integrated in the same circuit ...

This paper proposes a multi-stage power generation system suitable for renewable energy sources, which is composed of a DC-DC power converter and a three-phase inverter. The DC-DC power converter is a boost converter to convert the output voltage of the DC source into two voltage sources. The DC-DC converter has two switches operates like a continuous conduction mode. The input current of DC-DC...

The present paper describes the steady-state response and control of power in transmission line equipped with FACTS devices. Detailed simulations are carried out on two-machine systems to illustrate the control features of these devices and their influence to increase power transfer capability and improve system reliability. The DPFC is derived from the unified power-flow controller (UPFC) and ...

This paper introduces the concepts of platformless DC connections of offshore wind turbines. First, the paper describes the possible and preferred wind turbine drivetrain arrangements capable of producing sufficiently high DC voltage. Then, the electrical system designs appropriate for the platformless DC architectures are discussed. After that, the potential economic benefits of direct DC conn...

This paper presents a soft-switching DC-DC boost converter, which can be utilized in renewable energy systems such as photovoltaic array, and wind turbine connections to infinite bus of a big power network, using grid connected inverters. In the proposed topology for the DC-DC boost converter, the main and the auxiliary power switches are turned on and turned off with zero voltage switching (ZV...

Major issues of NBI power supplies are a high-speed switching, regulation and transmission of dc ultra high voltage, and suppression of surge energy input to the beam source at breakdown. A GTO(gate turn off thyristor) inverter type power supply where the control is performed at low voltage ac side was designed for the ITER NB. Based on the remarkable progress of a high power IEGT (injection en...

we report the direct soft chemical synthesis and characterization of a family of face centered cubic (fcc) and partially ordered face centered tetragonal (fct) fept nanoparticles (nps) suitable for biomedical applications. both fcc and partially ordered fct-fept nps are synthesized by employing a simple polyol method. by using polyvinyl pyrolidone (pvp) as a stabilizer in various ratios during ...