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Abstract

Recently, solar photovoltaic power generation technology isdeveloping quickly, which became one from the world’s fastest developingnew powers. And also the building integrated photovoltaic (BIPV) powergeneration product is a trend for the future, however the PV modules within this systemare easily taught in surrounding structures and trees, which could form apartial shadow, the new place phenomenon may seem once the traditionalcentralized structure and string structure work under this conditions, whichcan seriously modify the existence and conversion efficiency of PV modules.Therefore, this paper takes the Electricity-module-based photovoltaic grid-connected power system that is appropriate for that BIPV system because the research object,and focus the Electricity/Electricity ripper tools topology of Electricity module. MPPT controlstrategy, Electricity/AC grid-connected control strategy thorough.A front-finish Electricity module in line with the flyback ripper tools was created, whichhas the benefits for example simple structure, high current gain, low voltageripple, simple to parallel, electrical isolation between input and output, etc. Andits operation principle was examined at length, the little-signal mathematicalmodel according to condition-space averaging method started, the snubbercircuit of leakage inductance was examined, and also the design approach to thecircuit parameters was handed.In line with the analysis and comparison from the conventional perturbationand observation method and variable step size perturbation and observationmethod, a hysteresis-comparison-based variable-step perturbation andobservation method was suggested, which eliminated power oscillation nearthe maximum power point and power misjudgment by hysteresiscomparison, solved the contradiction between tracking precision and speed byvariable step.A dual-closed-loop grid-connected control strategy made up of DCbus current exterior loop and grid-connected current inner loop wasresearched and style.

A grid-connected inverter system structure of double closed loop control was examined at length, and also the current exterior loop,current inner loop control block diagram and also the design approach to controllerparameters in line with the pole placement method was handed, according to theanalysis of grid-connected inverter mathematical model. So as toenhance the anti-interference ability from the system, the current feedforwardlink has been around since current inner loop, which could completely eliminate theinterference created by the grid current fluctuations. Experimental resultsdemonstrate the practicality from the plan.A Electricity-module-based photovoltaic grid-connected power systemexperimental platform was built, the related hardware and softwarewere designed, and also the experiments were transported out based on the schemeproposed within this paper, the experimental results demonstrate the practicality ofthis proposal plan.

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