A control method for a photovoltaic storage microgrid grid-connected power generation system

Abstract

The invention discloses a control method for a grid-connected power generation system of an optical storage microgrid. According to the method, a photovoltaic power generation power supply is connected with a direct-current (DC) bus through a boost converter, and an energy storage module is connected with the DC bus through a bidirectional DC-DC converter; a DC side of a DC-AC (Alternating Current) grid-connected inverter is connected with the DC bus, and an AC side of the DC-AC grid-connected inverter passes through a filtering inductor and then is connected with a power grid and a load respectively; the photovoltaic power generation power supply is subjected to maximum power tracking control and constant-voltage control respectively through a boost converter control strategy according to the charging state of the energy storage module, the output power of the photovoltaic power generation power supply, the voltage drop conditions of grid connected points and the reactive power demand set value of the power grid, the charging and discharging of the energy storage module are controlled through a bidirectional DC-DC converter control strategy, and the voltage of the grid connected points is stabilized through a DC-AC grid-connected inverter control strategy. The method disclosed by the invention has the advantages that the stable grid connection of the optical storage microgrid is guaranteed, and the quality of electric power of the power grid is improved; the multi-functionalization of the grid-connected inverter is realized, and the cost is reduced; the new energy absorption capacity of the power grid is enhanced, so as to meet the demands of the power grid.

Description

Technical field: [0001] The invention belongs to the technical field of distributed power generation, and in particular relates to a control method for an optical storage microgrid grid-connected power generation system. Background technique [0002] At present, the proportion of photovoltaic power generation in the distribution network is increasing, and its independent grid-connected operation will definitely have a great impact on the power quality of the distribution network, which is not conducive to the stable operation of the grid. The grid-connected operation of the photovoltaic storage microgrid can smooth the output of photovoltaic power generation, stabilize the voltage, frequency and phase of the photovoltaic storage microgrid, and reduce the phenomenon of photovoltaic power generation curtailment. [0003] In the optical storage microgrid, the circuit structure of the microgrid inverter is the same as that of power quality control devices such as DSTACOM, DVR, a...

AI Technical Summary

Problems solved by technology

[0003] In the optical storage microgrid, the circuit structure of the microgrid inverter is the same as that of power quality control devices such as DSTACOM, DVR, and APF. However, in most practical applications, the function of the microgrid inverter is too single, resulting in relatively large Waste, and the control method is relatively simple, especially in complex working conditions, the switching is very uncontrollable

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