Method for supplying electricity to alternating current essential load by distributed power source in direct current micro-grid

Abstract

The invention discloses a method for supplying electricity to an alternating current essential load by a distributed power source in a direct current micro-grid. The method is characterized in that an AC / DC bidirectional transducer is arranged, the direct current end of the AC / DC bidirectional transducer is connected to a direct current bus, the alternating current end of the AC / DC bidirectional transducer is connected to an alternating current bus through a switching element set, the alternating current grid connection operating state of the AC / DC bidirectional transducer is achieved through the switching control of the switching element set, or the operating state that the direct current micro-grid directly supplies the electricity to the direct current essential load through the AC / DC bidirectional transducer is achieved. The method effectively solves the problem that coordination control among AC / DC bidirectional transducers and protecting and scheduling control of the direct current micro-grid and a main power grid are hard to match.

Description

Technical field [0001] The invention relates to a method for supplying power to an important AC load when a power system fails, and is particularly suitable for places where medium and small-capacity photovoltaics, wind power sources and energy storage components with high distribution density are interconnected via a DC micro-grid. Background technique [0002] DC microgrid refers to a small, modular and decentralized DC power supply network formed by connecting scattered distributed power generation resources in a certain area. The DC microgrid can be connected to the main grid through an AC / DC two-way converter and is in an AC grid-connected operation state; it can also operate independently and autonomously to maintain power supply to important users. [0003] Current research and engineering demonstrations generally use AC microgrids to maintain power supply to AC important loads. The problem to be solved urgently in this method is: how to realize the energy management betwee...

AI Technical Summary

Problems solved by technology

The problems to be solved urgently in this way are: how to realize the energy management between multiple distributed power sources and loads in the AC microgrid and the coordinated control between each power supply under the condition of no fault, how to solve the isolation and isolation of fault points in the AC microgrid Whether the microgrid can continue to operate stably after the fault point is isolated

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