The Journal of Engineering (May 2019)
Fast compensation of DC bus voltage drops using modular multilevel converters
Abstract
For a DC grid using modular multi-level converters (MMCs) fast control of the DC bus is an important requirement. A control design is presented where a sudden DC voltage drop is compensated without any influence on the AC side. Using a suitable pattern in the MMC internal circular currents, the DC current can be adjusted and the MMC can be brought to a new steady state with symmetrised arm energies within few milliseconds.
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