Design Of 50 MWp Photovoltaic Power Station In Qianan County

As technology advances,the rate of energy consumption is gradually accelerating.While fossil fuels are becoming increasingly scarce,the development of renewable energy is currently the world’s top priority.Solar energy,as a clean energy source,has be en vigorously developed by governments of various countries.China has only formally entered the photovoltaic industry since the 1970s,and after five decades of development,the cumulative installed capacity of China now ranks first in the world for six consecutive years.In response to the national call,This paper takes a 50 MWp centralized grid-connected PV plant in the Qian’an area as the research object to design the electrical aspects.This paper first analyzes the sunshine resources,meteorological environment and geology of Qian’an area,and determines that the site is suitable for building a photovoltaic power station based on the above conditions.The average annual solar radiation in the selected area is about5090.5 MJ/m~2,which is a solar resource-rich area.The land is mostly saline and sandy,which is suitable for building large centralized grid-connected photovoltaic power stations.According to the local grid demand in Qian’an area,the installed capacity of the built power plant was determined to be 50 MWp.Secondly,PVsyst software was used to simulate the local insolation environment to determine the maximum radiation and the highest power generation efficiency when the PV panels were installed at 43°fixed.Polycrystalline silicon cells w ith a cell capacity of255 Wp were selected as PV modules,and the panels were installed at a distance of 6.8 m from north to south based on the insolation angle in Qian’an County,as calculated.The series and parallel connection scheme of PV array adopts the form of 22 pieces of 255 Wp PV modules as a string.Finally,the electrical primary and secondary design of the PV plant was carried out.66 k V main wiring was adopted in the form of single busbar wiring,and 35 k V main wiring was adopted in the form of single busbar segmentation wiring.The main transformer is an on-load regulator with a rated capacity of 1000 k VA,and the short-circuit level of electrical equipment is designed at31.5 k A.Suitable grid-connected controller,photovoltaic inverter,sink box and secondary equipment group cabinet and other related electrical equipment are selected,and lightning protection and grounding and other protective measures are designed.To protect the power station equipment,design and plan the monitoring syste m,communication system and control system of the power station.Analyze the principle of relay protection devices and the configuration of electrical measurement and transformers.Introduce the electrical secondary equipment grouping cabinet and arrangement.Regarding secondary wiring,the article focuses on the configuration of electrical measurement and transformers for PV power plants.The construction of this project is completed and is now delivered.Based on the actual power generation and access data in 2020,it is clear that the design of the electrical aspects of this PV power plant meets the grid connection requirements of the power grid in Qian’an County.This power plant has improved the energy structure of Qian’an area after accessing and can play a part of technical reference for future PV power plant design work.