The popularity of the solar photovoltaic market has driven the development of the solar inverter industry. Generally speaking, solar inverters are divided into three types: centralized inverters, string inverters, and micro inverters.
Centralized inverters, which converge first and then invert, are mainly suitable for large centralized power plants with uniform illumination. Due to its low cost, it is mainly used in large-scale centralized photovoltaic power stations such as large factories with uniform sunlight and desert power stations.
String inverters are used for inverting and then converging, mainly for small and medium-sized rooftops, small ground power plants, and other scenarios. The application scenarios are more diverse, and can be applied to various types of power stations, such as centralized power stations, distributed power stations, and rooftop power stations, with a slightly higher price than centralized power stations.
Micro inverters are directly inverted and connected to the grid, mainly suitable for household and small distributed scenarios. Generally, the power is below 1kw, mainly applicable to distributed household and small distributed industrial and commercial rooftop power stations, but the price is high, and it is difficult to maintain in case of failure.
Low cost leadership
The inverter industry before 2010 did not belong to China. As the most important photovoltaic market, Europe accounted for more than 60% of the global new photovoltaic installed capacity each year between 2004 and 2011. As a major electrical power, SMA, a photovoltaic giant, first developed photovoltaic inverters in 1987, and introduced the first commercial series inverter and centralized inverter, leading the industry by relying on technical advantages.
The global market is almost monopolized by European companies, and among the top 10 photovoltaic inverter shipments, except for three North American companies, the rest are from Europe. Five European companies, SMA, KACO, Fronius, Ingeteam, and Siemens alone, account for 70% of the market share. The market share of SMA companies has reached 44%, equivalent to half of the photovoltaic inverter market.
At a time when photovoltaic development is in full swing in Europe, China’s photovoltaic development is still in its infancy: the lack of technological research and development achievements has become the biggest factor restricting development. As we all know, photovoltaic inverters connect the photovoltaic array and the power grid, which can convert the DC power generated by the system into AC power required for life through power electronic conversion technology, and can be called the heart of the entire photovoltaic system.
As the “brain” of photovoltaic power generation systems, its production and manufacturing combine power system design technology, semiconductor technology, power electronics technology, microcomputer technology, software algorithm programming technology, etc. In a highly sophisticated industry that requires a high degree of technical cooperation to complete, inverters are more like leaders deploying other components with their brains, and their every move will directly affect the overall trend of photovoltaic systems.
Its conversion efficiency and reliability have also become the main indicators to judge the performance of the inverter. As long as the power becomes high, it can mean low loss, which is one of the important breakthroughs in reducing the cost of electricity per kilowatt hour for photovoltaic projects. In December 2003, Sungrow Power introduced China’s first 10kW photovoltaic grid connected inverter with independent intellectual property rights, making a significant step forward in conversion efficiency and thus breaking foreign monopolies.
Optical storage integration is an inevitable trend
The traditional grid-connected photovoltaic inverter can only perform one-way conversion from DC to AC power, and only generates electricity during the day. The power generated can also be affected by the weather, which has unpredictable issues. However, the energy storage inverter integrates the functions of photovoltaic grid-connected power generation and energy storage power stations, storing electric energy when it is abundant, and inverting the stored electric energy when it is insufficient to output it to the grid, balancing the power consumption differences between day and night and different seasons, It plays a role in peak shaving and valley filling.
The energy storage inverter and grid connected inverter have the same technology. Although the protection circuit and buffer circuit are different, the hardware platform and topology structure are similar, so the cost reduction path is basically consistent with the photovoltaic inverter.
In the short term, the demand for energy storage and installation is mainly driven by the policy side, and affected by the constraints on absorption space and electricity volatility, various governments have accelerated the introduction of a series of relevant policies to encourage the energy storage market. Some provinces and cities in China have even mandated the allocation and storage of new energy.
In the long run, the integration of optical and storage is an inevitable trend, and policies should first promote the allocation and storage of new energy. In theory, in a situation where photovoltaic power is completely supplied, it is necessary to configure 1:3 to 1:5 energy storage to achieve uninterrupted power supply. Optical storage integration is expected to become a future clean energy solution.
Post time: Mar-24-2023