Design Of 3 KW Distributed Grid-connected PV System And Comprehensive Benefit Analysis

Along with the advancement of the global energy crisis and energy-saving emission reduction strategies, developing the renewable clean energy has become the inevitable trend of social development, such as solar and wind power. Solar energy is a new kind of green and renewable energy, it has much advantages, for example, large reserves, economics, and clean and green and so on. Therefore, more and more people pay attention to the use of solar energy, and they are focus on the application of solar PV technology. Photovoltaic power generation system has the advantages of environmental protection, low-noise, wide application scope and favored, while distributed photovoltaic power generation by virtue of its unique advantages, has become a new way of energy applications, our nation are also actively promoting the policies to develop the distributed.Based on the understanding of the significance and development of distributed PV, this paper analyzed the advantages of photovoltaic power generation, identified the paper’s projects, designed 3 kW roof grid-connected photovoltaic system, the system which is located in Daiyue District,Tai’an city, Shandong Province. The article introduced the inhabitants distributed PV system components selection and overall design, which is the most important part of the photovoltaic power generation system is the PV modules and inverters. According to the parameters of the selected solar panels and physical models, simulation in MATLAB, analysised the output characteristics of solar cells, obtained photovoltaic cell has a unique maximum power point. Solar cell output characteristics influenced by the external environment factors such as light, temperature, in order to track the maximum power point of solar cells, improve the utilization efficiency of solar cells, always to join in the photovoltaic system controlled by the maximum power point tracking algorithm of DC link of transformation.This paper studied the application in small and medium-sized power grid-connected inverter, under the domestic load and generating capacity, this article choosed high-frequency isolated grid-connected inverter of a company, and the inverter uses a multi-level topologies. This paper introduced the parameter design of inverter, analysis the control strategy of DC/AC inverter circuit theory, and according to the theory of PI control and PR control simulation analysis, concluded that the output current of PR controlled closer to the interconnection requirements.Meanwhile, due to the energy and environmental situation and the country’s support for distributed solar power, residents distributed will be promoted, it will has a profound impact on social development. This paper respectively evaluate the comprehensive benefit of distributed photovoltaic power generation from four aspects, they are economic benefit, technical benefit, society benefit and environment benefit.