Key words: photovoltaic inverter 1500V photovoltaic power station

With the advent of affordable Internet, cost reduction, efficiency improvement and intelligent upgrading have become an urgent need of the photovoltaic industry. As the key equipment of photovoltaic power generation, the inverter, stimulated by favorable policies, constantly updates and iterates the technology and becomes the "engine" driving the affordable era. According to IHS 'latest forecast, more than 11 million photovoltaic inverters will be shipped worldwide in 2019 alone, most of which will be connected to software platforms and controlled by inverter companies. At the same time, the new development situation also puts forward higher requirements for the power level, voltage level, capacitance ratio and overload capacity of the inverter, which makes the development of inverter technology and market enter a new stage.

So, in the distributed photovoltaic, household photovoltaic, photovoltaic energy storage, photovoltaic heating, no subsidy projects, intelligent photovoltaic, and many other trends, what new trends will appear in the inverter industry? What new reshuffles and consolidation will take place? How can digital and intelligent upgrade of inverter bring function expansion? How does the new trend lead to the reintegration of inverter technology route? What new business opportunities and business models will emerge from these changes? This paper analyzes seven trends of inverter development, hoping to help readers to learn and understand.

The series inverter becomes the main stream

With the development of technology and market, the global inverter market presents a new development pattern. Due to the advantages of more flexible system design, lower loss in case of failure and lower life cycle maintenance cost, the series inverter has been widely used worldwide. In 2017, the shipment volume of the centralized inverter exceeded that of the centralized inverter for the first time. According to the report of GTM Research, in 2017, the total shipments of three-phase series inverters in the world exceeded 46GW, with a year-on-year growth of 49%, nearly 4GW higher than the centralized inverter. Group type inverter exceeds centralized type for the first time, share increases continuously.

In 2018, the photovoltaic inverter market is still dominated by centralized inverters and series inverters, while micro and distributed inverters account for a small proportion. With the rapid increase of the distributed photovoltaic market and the increase of the proportion of series inverters in centralized photovoltaic power stations, the market proportion of series inverters reaches 60.4%.Compared with centralized inverter, distributed photovoltaic inverter improves MPPT control effect, and has lower construction cost compared with serial inverter solution. Therefore, the market share shows a trend of increasing year by year.

1500V has become the mainstream of the industry

According to a report by the authoritative research institution IHS Market, the global scale of 1,500v photovoltaic power stations will exceed 100GW in the next two years. Compared with the traditional 1000V system, the 1500V system has a higher voltage level and a longer string length, greatly reducing the equipment cost, cable cost and construction cost. At the same time, the generation capacity is improved, and the BOS cost per watt is reduced by at least 5 cents, which is the best choice for the current design scheme of unsubsidized and low-subsidized national photovoltaic projects.

With the increase of 1500V system in the global pv market, the shipment of 1500V inverter is rising with the tide. According to the IHS report, 40% of the world's pv market excluding China in 2017 was 1500V for three-phase inverters. In 2018, this proportion has increased to 62%, surpassing 1000V across the board.IHS projects that the 1500V three-phase inverter share will continue to grow to 74% in 2019 and soar to 84% in 2020.

Digital, intelligent upgrade aiming at intelligent iot

In recent years, both domestic and foreign mainstream pv inverter suppliers have simultaneously targeted the intelligent iot field, successively developed new intelligent software technology platforms, and constructed digital services to create new revenue sources.

The key function of the inverter is to convert solar energy into electricity so that the power grid can be used. In the past, solar inverters were thought to be independent and not connected to each other. In the new digital energy world, however, software platforms are unlocking parts of equipment that were once isolated and separated.

Several international solar inverter suppliers have developed their own proprietary iot software platforms to sell solar, energy storage hardware and digital services to commercial chains, large utilities and other non-traditional customers, extending their reach to thousands of independent owners.

AI technology will also gradually be integrated into pv, including smart IV technology which is now being successfully applied on a large scale. Photovoltaic system will be inverter as the core, digital, intelligent and continue to improve. While comprehensively improving the power generation and operation and maintenance efficiency, it sets up the ultimate platform for future comprehensive energy services.

The inverter epitaxial extension function covers the core function

Photovoltaic inverter will add more and more energy management functions in the process of going digital and intelligent. First, photovoltaic energy storage management function. The importance of energy storage for large-scale grid-connected photovoltaic and other new energy is self-evident. The application of optical storage system further drives the inverter to evolve to the power station energy management center. Second, the safety management function. Dc pull arc detection, group