Micro-grid control method capable of significantly improving electric energy quality of micro-grid

Abstract

The invention discloses a micro-grid control method capable of significantly improving the electric energy quality of a micro-grid. The method can be realized by an Advanced f-P/V-Q controller. An Advanced f-P Drooping/V-Q Drooping algorithm link, a filter capacitor voltage loop and a filter inductance current loop are comprised. When a micro-grid system is in an island operation mode, through the changes of micro-grid voltage amplitude and frequency, the Advanced f-P/V-Q controller controls a micro-source to respond to the phenomena of the load change of the micro-grid, the output power fluctuation of other micro-sources and the like and to output the active power and the reactive power currently required by the micro-grid system, to stabilize the voltage frequency and amplitude of the micro-grid system, thus the electric energy quality of the micro-grid is significantly improved; and when the system is in a grid-connected mode, the Advanced f-P/V-Q controller automatically responds to the phenomena of the load change of the micro-grid, the output power fluctuation of other micro-sources and the like, and enables the micro-grid system to stably output the set power, and at present the voltage of the micro-grid system varies with the voltage of a distribution grid, thus the electric energy quality requirements of the micro-grid and the distribution grid are satisfied.

Description

Technical field [0001] The invention belongs to the technical field of control of microgrids and power distribution systems containing microgrids, and particularly relates to a microgrid control method that can significantly improve the power quality of the microgrid. Background technique [0002] Energy is the foundation for human survival and development. Electricity, as the cleanest and convenient form of energy, is the lifeblood of the national economy. Traditional primary energy sources such as coal and oil are non-renewable and will eventually be exhausted. Improving energy efficiency, developing new energy, and strengthening the use of renewable energy are the inevitable choices to solve the contradictions between the growing energy demand and energy shortage, energy utilization and environmental protection in the process of rapid economic and social development in my country. [0003] Microgrid is a cutting-edge technology emerging under the background of new energy power ...

AI Technical Summary

Problems solved by technology

When the micro-grid is connected to the distribution network on a large scale, the traditional distribution network will change from a passive receiving end to an active system, which will inevitably bring new problems and new influences to the power quality of the distribution network, including micro-source output. Intermittent changes in power lead to voltage fluctuations, voltage offsets, and frequency offsets; inrush current problems when microgrids and distribution networks are connected to the grid; microgrid reactive power circulation problems; large-scale power electronic devices and nonlinear loads Harmonic problem; three-phase voltage unbalance problem caused by single-phase load

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