Huawei has entered the PV inverter industry since 2013, and pioneered the technology of connecting two strings with one MPPT without using fuses, which has reduced a lot of costs for the later operation and maintenance of the PV industry. Since then, newly developed inverters have basically been designed according to this idea.

　　Before 2020, the component current is below 12.5A. In 2021, as the 182 and 210 size PV modules gradually occupy the mainstream, the module current will rise sharply, and the limitation of connecting two strings with one MPPT will come out.

　　(1) The current of a single string is fixed. If the current of the component increases, it is necessary to develop a new inverter to adapt to the new component, which will inevitably lead to an increase in cost.

　　(2) The need for fuses is based on the fact that the component power is below 300W and the short-circuit current of component is below 12.5A. According to EC62548 "Design Requirements for PV Arrays", if the short-circuit current of the module exceeds 15A, overcurrent protection devices must be configured. However, the short-circuit current of the new high-power components will basically exceed 15A, so it is not suitable for high-power components. In fact, for 600W+ modules, if two circuits are connected in parallel, it is equivalent to 4 circuits of 300W modules in parallel. If there is no overcurrent protection device, when a short-circuit fault occurs in the system, the energy of other strings cannot be prevented from flowing to the short-circuit point, which may cause damage to the components and cables, and even cause a fire.

　　In fact, there is a newly developed electrical structure that can adapt to the diversity of components, that is, one MPPT connects 4 strings. This structure can adapt to the crystalline silicon modules on the market.

　　Modules below 400W, current below 11A, one MPPT connected to 4 strings, can fit 156.75, 158.75 silicon wafer size modules;

　　400~550W modules, the current is above 11A, below 13.5A, one MPPT is connected to 3 strings, which can be suitable for 166 and 210 silicon wafer size modules.

　　Above 550W, the current is above 15A, one MPPT is connected to 2 strings, which is suitable for 182 silicon chip size components. If one MPPT has 50A current, it is connected to two strings, one string is 25A, and it can be adapted to 800W components in the future. . The life cycle of this model will also be very long.

　　At present, there is no 200kW+ inverter with this electrical structure on the market, so for all inverter manufacturers, who can be the first to mass-produce, who will take the initiative in the market and become the market leader.

　　Lithium-ion battery (LIB) has become the main energy storage solution in modern social life. Among them, lithium iron phosphate batteries are a perfect replacement for lead-acid batteries, and they are the first choice for grid-connected peak shaving, off-grid energy storage, PV energy storage, UPS, data center and other industries.

　　Solar power generation system with lithium battery energy storage system is a very promising clean energy.