Power optimizer helps solar photovoltaic cells improve efficiency

With the development of renewable energy, the application of solar photovoltaic power generation is becoming more and more widespread. However, the existing solar photovoltaic system architecture is very susceptible to the actual operating environment. For example, if a large tree is planted next to a house, the shade, fallen leaves, various debris and bird droppings that fall from time to time will block the solar panels and gradually reduce the total power generation of the photovoltaic system. For a solar photovoltaic power generation system, as long as a few panels are shaded or shaded by leaves, the power generation of the entire system will drop significantly. Specifically, as long as 10% of the solar panel area is covered, the total power generation of the system will drop by 50%. In addition, although the newly installed solar photovoltaic system will not have the problem of panel mismatch, as time goes by, the panels will continue to age, and imbalances will inevitably occur within the solar system.

Power Optimizer

The SolarMagic power optimizer launched by National Semiconductor makes full use of the company's analog power management chip technology. Even if the solar photovoltaic power generation system is subject to actual operating environments such as shadows, debris and aging of solar panels, this power optimizer can still reduce the decline in power generation. In a solar array using power optimizer technology and distributed MPPT, each panel is connected to a power optimizer device. The power optimizers perform dual tracking: on the one hand, they track the best local MPP; on the other hand, they convert the input voltage/current into different output voltage/current to maximize energy transmission in the system. The power optimizers communicate with each other in an indirect way. They have cognitive and self-organizing capabilities, can detect their own current and voltage environment and adjust themselves until the entire row reaches the optimal value, while reaching the local optimization point at the panel level. At the same time, the power optimizer architecture is perfectly compatible with existing multi-level inverters, which will make them run more efficiently because the bus voltage can be kept higher and more constant. Power optimizers are not limited to improving the performance of DC/DC converters. They can handle both excess and reduced energy situations, which means that panel mismatches caused by reflected excess light can be handled just as various shadows are handled; similarly, this means that power optimizers have the ability to respond to power changes by adding panels to a row (making the row produce more power) or removing one or two panels from a row (thus reducing power). Field tests have shown that SolarMagic chips can recover more than 57% of lost power generation. With SolarMagic technology, users can easily upgrade their solar systems after years of installation, significantly increasing the power generation of photovoltaic systems.

In March 2009, National Semiconductor helped optimize the performance of a solar cell system in an apartment building in Oakland, California, by adding SolarMagic power optimizers to about one-third of the panels in the photovoltaic system, which had a total of 204 solar panels, to improve its performance. After the project was completed, the total power generation of the system increased by 22.6%.

In addition to reducing the decline in the power generation of photovoltaic systems, SolarMagic technology is also highly flexible, giving photovoltaic system retailers more room to play when conceiving new system designs. In order to ensure that the configuration of solar panels and the power generation of the system are not affected by shadows, system design engineers have always had to reduce the size of solar panels and ignore the aesthetics of the appearance design. The entire design process is extremely time-consuming and costly. If SolarMagic technology is used, system engineers can not only improve the power generation efficiency of the PV system, but also beautify the appearance design more flexibly, for example: choose panels of different lengths, match panels of different brands together, and even use solar panels of irregular shapes.

By recovering the power generation loss caused by actual environmental factors, the launch of SolarMagic technology has made it possible to install photovoltaic systems in more places. Many places that were considered unsuitable for installing photovoltaic systems can now use solar energy with the help of SolarMagic technology. In other words, the practicality of SolarMagic technology has greatly expanded the potential market for solar energy systems.

Existing photovoltaic systems have many potential reliability problems such as overvoltage. The SolarMagic chip can adjust the power fed from the solar panel to the inverter, solving problems such as overvoltage, thereby maintaining the stability of the solar system for a long time. In addition, since the DC/AC conversion function is directly controlled by the central control, the entire conversion process can maintain the highest efficiency within the specified voltage range. In other words, even if the number of solar panels is not increased, SolarMagic technology can still further increase the power generation of the system.