What is the development trend of solar inverter?

Solar Inverter is the brain and heart of photovoltaic power generation system. In the process of solar photovoltaic power generation, the power generated by photovoltaic array is DC power. However, many loads need AC power. The DC power supply system has great limitations, so it is inconvenient to change the voltage, and the application range of loads is limited. Except for special electric loads, inverters are required to convert DC power into AC power. Photovoltaic inverter is the heart of solar photovoltaic power generation system. It converts the direct current generated by photovoltaic modules into alternating current, which is delivered to local load or power grid, and is a power electronic device with relevant protection functions.

The solar inverter is mainly composed of power module, control circuit board, circuit breaker, filter, reactor, transformer, contactor and cabinet, etc. The production process includes electronic parts pre-processing, whole machine assembly, testing and whole machine packaging, etc. Its development depends on the development of power electronics technology, semiconductor device technology and modern control technology.

For solar inverters, improving the conversion efficiency of power supply is an eternal topic, but when the efficiency of the system is getting higher and higher, nearly 100%, further improvement of efficiency will be accompanied by low cost performance. Therefore, how to maintain a high efficiency and good price competitiveness will be an important topic at present.

Compared with the efforts to improve the efficiency of inverter, how to improve the efficiency of the whole inverter system is gradually becoming another important topic of solar energy system. In a solar array, when the partial shadow of 2%-3% area appears, for the inverter with one MPPT function, the output power of the system at this time will even drop by about 20%. In order to better adapt to the similar situation, it is a very effective method to adopt one-to-one MPPT or multiple MPPT control functions for single or partial solar module.

Because the inverter system is connected to the grid, the leakage of the system to the ground will cause serious safety problems. In addition, in order to improve the efficiency of the system, most solar arrays are connected in series to form a very high DC output voltage. Therefore, it is easy to produce DC arc between electrodes due to abnormal conditions. Because of the high DC voltage, it is very difficult to extinguish arc, and it is very easy to cause fire. With the wide application of solar inverter system, the problem of system security will also be an important part of inverter technology.

In addition, the power system is welcoming the rapid development and popularization of smart grid technology. A large number of new energy power systems such as solar energy are connected to the grid, which brings new technical challenges to the stability of smart grid system. Designing an inverter system compatible with smart grid more quickly, accurately and intelligently will be a necessary condition for the future solar inverter system.

Generally speaking, the development of inverter technology is along with the development of power electronics technology, microelectronics technology and modern control theory. With the passage of time, the inverter technology is developing towards higher frequency, higher power, higher efficiency and smaller volume.