The grid connected photovoltaic power generation system consists of a photovoltaic cell array, a controller, and a grid connected inverter, which directly feeds electrical energy into the public grid through the grid connected inverter. By directly inputting electrical energy into the power grid, there is no need to configure batteries, which saves the process of battery energy storage and release, reduces energy loss, saves space occupied, system investment and maintenance, and reduces costs; On the other hand, the power generation capacity can be large and can ensure the reliability of the power supply for electrical equipment. However, due to the parallel connection between the inverter output and the power grid, it is necessary to maintain the consistency of electrical characteristics such as voltage, phase, and frequency between the two sets of power sources, otherwise it will cause mutual charging and discharging between the two sets of power sources, causing internal friction and instability of the entire power system.

1.并網光伏發電系統幾種形式

1. Several forms of grid connected photovoltaic power generation system

并網光伏發電系統是目前發展為迅速的太陽能光伏發電應用方式，隨著光伏建筑一體化的飛速發展，各種各樣的并網光伏發電系統都得到了廣泛的應用。并網光伏發電系統包括如下幾種形式：

Grid connected photovoltaic power generation system is currently the fastest developing application of solar photovoltaic power generation. With the rapid development of photovoltaic building integration, various grid connected photovoltaic power generation systems have been widely used. The grid connected photovoltaic power generation system includes the following forms:

①純并網光伏發電系統。

① Pure grid connected photovoltaic power generation system.

②具有UPS功能的并網光伏發電系統。

② A grid connected photovoltaic power generation system with UPS function.

③并網光伏發電混合系統。

③ Grid connected photovoltaic power generation hybrid system.

2.并網光伏發電系統優點

2. Advantages of grid connected photovoltaic power generation system

太陽能并網光伏發電系統通過把太陽能轉化為電能，不經過蓄電池儲能，直接通過并網逆變器，把電能并入電網。太陽能并網光伏發電系統代表了太陽能光伏發電系統的發展方向，是21世紀具吸引力的能源利用技術。與離網太陽能光伏發電系統相比，并網光伏發電系統具有以下優點：

The solar grid connected photovoltaic power generation system converts solar energy into electrical energy, without storage batteries, and directly integrates electrical energy into the grid through grid connected inverters. The solar grid connected photovoltaic power generation system represents the development direction of solar photovoltaic power generation systems and is the most attractive energy utilization technology in the 21st century. Compared with off grid solar photovoltaic power generation systems, grid connected photovoltaic power generation systems have the following advantages:

①利用清潔干凈、可再生的太陽能發電，不耗用不可再生資源，使用中無溫室氣體和污染物排放，與生態環境和諧，符合經濟社會可持續發展戰略。

① Utilizing clean and renewable solar power generation, without consuming non renewable resources, without greenhouse gas and pollutant emissions during use, is in harmony with the ecological environment, and is in line with the sustainable development strategy of the economy and society.

②所發電能饋入電網，以電網為儲能裝置，省掉蓄電池，比離網太陽能光伏發電系統的建設投資可減少35％～45％，從而使發電成本大為降低。省掉蓄電池并可提高系統的平均無故障時間和蓄電池的二次污染。

② The generated energy is fed into the power grid and used as an energy storage device, eliminating the need for batteries. Compared to the construction investment of off grid solar photovoltaic power generation systems, the investment can be reduced by 35% to 45%, thereby greatly reducing the cost of power generation. Eliminating batteries can improve the average time between failures of the system and the secondary pollution of batteries.

③在設計中使太陽能電池組件與建筑物完美結合，既可發電又能作為建筑材料和裝飾材料，使物質資源充分利用發揮多種功能，不但有利于降低建設費用，并且還使建筑物科技含量提高。

③ In the design, the perfect combination of solar cell modules with buildings can generate electricity and serve as building materials and decorative materials, fully utilizing material resources and exerting various functions. This not only helps to reduce construction costs, but also improves the technological content of buildings.

④分布式建設，就近就地分散發供電，并入和退出電網靈活，既有利于增強電力系統抵御自然災害的能力，又有利于改善電力系統的負載平衡，并可降低輸電線路損耗。

④ Distributed construction, with locally distributed power generation and supply, and flexible integration and exit from the power grid, not only enhances the ability of the power system to withstand natural disasters, but also improves the load balance of the power system and reduces transmission line losses.

⑤可起調峰作用。并網光伏發電系統是世界各發達在光伏應用領域競相發展的熱點和重點，是世界太陽能光伏發電的主流發展趨勢，市場巨大，前景廣闊。

⑤ It can play a peak shaving role. Grid connected photovoltaic power generation system is a hot and key development topic in the photovoltaic application field in developed countries around the world, and it is the mainstream development trend of solar photovoltaic power generation in the world. The market is huge and the prospects are broad.