Energy storage interface converter control method capable of suppressing micro-grid bus voltage fluctuation

Abstract

The invention relates to an energy storage interface converter control method capable of inhibiting micro-grid bus voltage fluctuation, greatly reduces the system operation time as a simplified current prediction model target function is used, and enables a control circuit to be convenient to achieve. The method is characterized in that a droop coefficient in the control circuit is adjusted according to a bus voltage change rate, the bus voltage change can be more visually reflected, moreover, under the action of model current prediction control, even if unplanned isolated island operation ordistributed energy intermittent operation occurs, voltage fluctuation can still be well suppressed, a bus voltage drop value is reduced, the dynamic response is improved, voltage sensitive load shedding operation is avoided, and operation reliability of the direct-current microgrid is remarkably improved.

Description

technical field [0001] The invention relates to a control technology of a converter, in particular to a control method of an energy storage interface converter capable of suppressing voltage fluctuations of a microgrid bus. Background technique [0002] Facing the severe situation of non-renewable energy depletion and environmental problems, the technology of connecting distributed energy such as wind energy and light energy to the grid through power electronic converters has gradually attracted attention. Due to its simple structure and higher efficiency, the DC microgrid has prominent advantages in the grid-connection of distributed energy sources. However, the DC microgrid is easily affected by disturbance conditions and intermittent operation of distributed energy sources, which will cause the quality of output power to decline. Voltage-sensitive loads will also be greatly affected during operation. Although energy storage devices can suppress voltage fluctuations at pr...

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Problems solved by technology

[0003] The present invention aims at suppressing the voltage fluctuation of the DC micro-grid bus, and proposes a control method for the energy storage interface converter that can suppress the voltage fluctuation of the micro-grid bus, and the outer loop is based on the DC bus voltage change rate adaptive variable coefficient drooping control circuit , the inner loop is based on the model-predicted current control circuit. When the bus voltage fluctuates, the circuit can realize the release and absorption of the energy storage unit more quickly to resist the fluctuation of the DC bus voltage and ensure the stable operation of the DC microgrid. , significantly improving its operational reliability

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