Dc Modules In Bipv System Research And Implementation

Along with the social and economic development, human demand for energy ismore and more intense, while the traditional fossil fuel, it faces with the exhaustion andenvironmental pollution at any time, so looking for alternative energy has become theurgent matter. Solar energy as the one kind of new energy，which is inexhaustible,pollution-free and clean, become the inevitable focus that each country pays keyattention. This paper selects the hot research issue-Building Integrated Photovoltaicsystem (BIPV)-to study, analyzing the topology structure of BIPV system, which isbased on the dc model, comparing the maximum power point tracking algorithm andchoosing the suitable dc transform circuit for dc module, and finally making theexperimental demonstration for corresponding technological features.BIPV system has a variety of topology types, which have different characteristicsand advantages. Among them the centralized, AC module type and DC module type arethe most widely used structure forms. Through the comparative analysis found that dcmodule with concentrated inverter type has the out weight advantages, such as energytransmission efficiency, failure match performance and expansion ability, it is verysuitable for the BIPV system.Because the solar cell is a nonlinear source, and its output characteristics will beinfluenced by the outside environment, so its output power will also changecontinuously, which needs to adopt the MPPT technology, guaranteeing that solar arraysoutput power in maximum degree. This paper makes a comparison for several mostcommonly used power tracing methods and detailed analysis for various controlalgorithm. Based on the feature of modular DC BIPV system, a MPPT process ofCVT-INC is selected for this system.For DC module as the most critical part of the modular DC BIPV system,whoseperformance will affect the efficiency, reliability, volume and power capability of thewhole system directly, so the DC module is given a emphatic analysis. First, severalkinds of DC/DC converter are compared in structure topology and characteristic, andgiven introduces to characteristics of DC/DC converter for the photovoltaic system. Then, several full-bridge DC/DC converter topology are provided，and determined animproved ZVZCS phase-shifted full bridge DC/DC converter as the topology of DCmodule to meet the requirements of the BIPV system. Finally, the working principle ofthis topology and soft-switching conditions are introduced.Based on the above comparative analysis, the DC module prototype is maded,experimental verification of the technical solution adopted. Experimental resultsdemonstrate the techniques used in this article.