High-voltage direct-current power

In Norway and Romania, hydrogen production and export is in direct competition with electricity transmission via high-voltage direct-current lines (HVDC). This solution is particularly attractive because hydropower is a non-fluctuating renewable energy source and does not destabilise the grid, as, for example, wind or solar power do. 

Commercially available regulated high-voltage direct current (d.c.) power supplies are of three types a bench top rack-mount unit with multiple features, a compact modular-type unit with... 

The previous chapters address various aspects of quantitative bond graph-based FDI and system mode identification for systems represented by a hybrid model. This chapter illustrates applications of the presented methods by means of a number of small case studies. The examples chosen are widely used switched power electronic systems. Various kinds of electronic power converters, e.g. buck- or boost converters, or DC to AC converters are used in a variety of applications such as DC power supplies for electronic equipment, battery chargers, motor drives, or high voltage direct current transmission line systems [1]. 

The basic design of the iontophoretic devices is a direct current power source and two electrodes. Platinum is the commonly used material for the electrodes, since it is nontoxic, has high oxidation voltage, slow degradation, and low ion release (Figure 26.1). 

A calutron consists essentially of an intense source of uranium ions, a way to accelerate the ions to high energy within a vacuum system, and a way to collect the uranium-235 and uranium-238 ions after they have moved in separate arcs between the poles of a very large electromagnet. The components at the heart of the system are ion sources, collectors, and high-voltage, regulated direct-current power supplies (Lore, 1973 London, 1961 USDoE, 1980). 

The power supply for the electrolysis cell is usually supplied as a high voltage AC current. It must be rectified to direct current and reduced to the required voltage for the cell. 

For those applications where high efficiency is important, synchronous rectification may be used on the higher current (power) outputs. Synchronous rectifier circuits are much more complicated than the passive 2-leaded rectifier circuits. These are power MOSFE B, which are utilized in the reverse conduction direction where the anti-parallel intrinsic diode conducts. The MOSFET is turned on whenever the rectifier is required to conduct, thus reducing the forward voltage drop to less than O.f V. Synchronous rectifiers can be used only when the diode current flows in the forward direction, that is in continuousmode forward converters. 

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