Method for improving adaptability of distributed photovoltaics to AC/DC hybrid microgrid

Abstract

The invention provides a method for improving adaptability of distributed photovoltaics to an AC / DC hybrid microgrid. The method includes the steps of determining double closed loop control parametersof a distributed photovoltaic grid-connected system under a strong power grid condition, the double closed loop control parameters including a proportional control factor of a PI controller, an integral control factor of the PI controller and a capacitance current feedback factor; realizing virtual shunt impedance based on output impedance under a weak power grid condition; and determining valueranges of the parameters and shunt inductance of a phase lag link after system compensation. The method provided by the invention ensures that the system can stably run under the strong power grid condition, and at the same time, can satisfy requirements of a stable state and a transient state; and improves adaptability of the system to a weak power grid, i.e., through double closed loop parametersetting under the strong power grid condition, the method provided by the invention ensures grid connection performance under the strong power grid condition, and a method of lag link compensation and shunt inductance after adoption of virtual shunt impedance is employed to improve adaptability of the system to the weak power grid.

Description

technical field [0001] The invention relates to a method for improving adaptability of a microgrid. In particular, it relates to a method for improving the adaptability of distributed photovoltaics to an AC / DC hybrid microgrid. Background technique [0002] With the continuous advancement of my country's industrial process, energy depletion and environmental pollution have gradually become the main factors that curb the progress of modern industry. New energy technologies represented by photovoltaics and wind turbines have gradually entered people's field of vision and gradually occupied an increasing role in my country's energy structure. proportion. The characteristics of distributed photovoltaics, such as self-use and adaptation to local conditions, have developed rapidly in my country. As a key interface between distributed photovoltaics and AC / DC hybrid microgrids, the performance of grid-connected inverters has a decisive impact on the grid-connected performance of di...

AI Technical Summary

Problems solved by technology

In this case, the total harmonic distortion (total harmonic distortion, THD) and power factor (power factor, PF) of the grid-connected current of the distributed photovoltaic grid-connected system that has been tuned and operated well under the condition of a strong grid may no longer be Meet the requirements of relevant grid-connected standards

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