Roof Distributed Photovoltaic Power Generation Grid-connected Design And Benefit Analysis

With the rapid development of the global social economy,traditional energy resources are decreasing,and the contradiction between energy and environment is becoming increasingly prominent.The development and utilization of new energy has become a common concern of all countries.The energy consumption in the construction sector accounts for a high proportion of the total energy consumption of the whole society,and the construction industry is the main force for energy conservation and consumption reduction.The development of green buildings is an important direction for the development of China's current construction industry.This paper takes a green building office building photovoltaic power generation system as the research object,starting from the grid-connected converter control strategy and simulation to the actu al engineering design,the following research is carried out:Firstly,the principle and implementation process of photovoltaic power point tracking(MPPT)control are analyzed in depth.Compared with the advantages and disadvantages of traditional MPPT me thods,in order to ensure the tracking speed and accuracy of MPPT,the traditional fixed-step perturbation observation method is used.The improvement is carried out,and the MPPT process is realized by a variable step disturbance observation method.The simulation model is built in Matlab/Simulink to verify the method.Secondly,considering the large-scale new energy buildings connected to the grid,the original equivalent damping and inertia of the power system will be lower,which will worsen the transie nt stability of the power system,using a virtual synchronous generator.,VSG)inverter control strategy provides the necessary damping and inertia for the system.The article deeply analyzes the realization process of VSG,designs the virtual governor an d virtual excitation system,and makes corresponding simulation experiments,indicating that the system can Actively participate in the power system frequency response.Thirdly,a 50.05 kWp rooftop photovoltaic power generation grid-connected system was designed.The system is located in the Chengguan District of Lanzhou City,Gansu Province,and the Gansu Civil Engineering Science Research Institute of Duanjiatan 1188#.The article introduces the selection and control methods of the various components of th e photovoltaic system and the overall design process.Considering that the roof type of the building is flat roof,the roof area is 1158.74 square meters,and there is a roof tank,stairwell,etc.In the case of insufficient roof area,after analysis and c omparison,KC175 GT polysilicon solar panels 13 strings and 22 sets are selected.A total of 286 blocks make up a small grid.The component has an azimuth of 0° and an inclination of 35°.The grid-connected inverter adopts the 10 kW type,the master-slave grid-connected power generation,adopting a master-slave structure.Finally,the power generation of the building was actual measurement.The measured results show that the first year of power generation reached 64.8194 kW,equivalent to 21.26 tons of standar d coal.The completion of the power station meets the requirements for new energy generation in the review of green buildings,and has made great contributions to the energy-saving renovation of the entire building.The results show that over time,the pow er generation is attenuated too fast,exceeding the design expectations.How to stabilize the power generation within a reasonab le attenuation range is the next research direction.