Method for maintaining voltage division curve dynamic droop control of micro-grid bus in energy storage link

Abstract

The invention relates to the technical field of energy storage system droop control of a DC micro-grid, in particular to a method for maintaining voltage division curve dynamic droop control of a micro-grid bus in an energy storage link. The method comprises dividing the energy storage link into a system stable non-working zone, an energy storage charging / discharging control blind zone, and an energy storage charging / discharge dynamic droop control zone; for the energy storage charging / discharge dynamic droop control zone, using battery SOC-based and virtual impedance dynamic droop control; for the energy storage charging / discharging control blind zone, determining curve droop control of an exponential function according to the coordinates of the intersection point and the function derivability of the energy storage charging / discharging control blind zone and the energy storage charging / discharge dynamic droop control zone. The control method designs and determines the control flow ofthe energy storage link in combination with the two characteristic working zones, expands the control range of the energy storage link, fundamentally solves the power distribution of the energy storage link, enables the output power finally to tend to be equal, compensates for a voltage drop difference caused by the droop control, makes the system operate stably.

Description

technical field [0001] The invention belongs to the technical field of droop control of an energy storage system of a DC microgrid, and in particular relates to a dynamic droop control method for maintaining a microgrid bus voltage partition curve in an energy storage link. Background technique [0002] As the proportion of renewable energy in the modern power system continues to increase, scholars have proposed the concept of a microgrid to achieve efficient control of various forms of renewable energy in the region. At present, there are DC micro-grid, AC micro-grid and AC-DC hybrid micro-grid, among which photovoltaic and wind power are the most widely used. The use of new renewable green energy can alleviate the current energy crisis. Renewable energy such as photovoltaic power generation has attracted more and more attention, and energy storage technology is an indispensable part of photovoltaic power generation, so advanced energy storage technology is in It is a key ...

AI Technical Summary

Problems solved by technology

However, when the voltage change value is relatively small relative to the adjustment range of the bidirectional DC / AC inverter and is not within the adjustment control range of the bidirectional DC / AC inverter; when the relative adjustment range of the energy storage link is relatively large and is not within the adjustment range of the energy storage link, there is The control blind zone cannot satisfy the smooth control of DC side bus voltage stability under various circumstances

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