【XWBOO Market Analysis】 Space engineering is a great feat of human beings, and it also affects the development of a country in politics, military affairs, economy, science and technology, so it is regarded as a significant project of far-reaching significance in most countries. In many projects of space engineering, artificial satellite is a very special existence.
Man-made satellite is a device that is built by man through science and technology and launched into space with the aid of space vehicle such as rocket. This device basically moves in accordance with the laws of celestial mechanics, but there are many things to consider in the actual operation, such as solar radiation, solar drag, atmospheric drag, gravitational attraction of other galaxies, and so on. As a result, the design and construction process is very complex, and there are many problems to be solved. Among them, the problem of energy is one of the most difficult problems of artificial satellite at present.
Artificial satellites usually have certain functions, so they can be generally divided into three categories: Scientific satellites, technological test satellites and application satellites, all of which are equipped with instruments for exploration, research and communication. As well as protection against external interference. This also makes the satellite in the operation process, needs to solve these equipment's power supply demand. Fortunately, the emergence of photovoltaic technology has successfully solved this problem.
Most satellites in space today are powered by photovoltaic cells, and light in the universe is better than near Earth. But could photovoltaic cells work better in the universe? The answer is no. In fact, damage to the photovoltaic cells from the cosmic environment directly affects the life of the satellite.
Although sufficient illumination can give a photovoltaic panel a better environment for power generation, and the temperature environment of the universe can effectively avoid damage to the panel due to high temperatures, But there is another factor in the universe that affects photovoltaic cells - radiation. Without the protection of the atmosphere, certain types of radiation can directly damage photovoltaic devices exposed to orbit, reducing their performance and reducing their lifetime.
The specific reasons are more complicated to describe. Put simply, when a photovoltaic cell absorbs light, energy is transferred to negatively charged electrons in the photovoltaic material. And generates a current through the photovoltaic during the release of the charge carriers. Some radiation in the universe causes atoms to shift, limiting the lifetime of carriers, and damaging photovoltaic cells, which become less and less efficient in long-term use.
So is there any way to avoid or mitigate this negative effect from radiation? In fact, the idea is very simple, as long as the photovoltaic cell thin on it. As the photovoltaic cell becomes thinner, the transport path of charge carriers becomes shorter, the effect of atomic displacement becomes smaller, and the lifetime of the photovoltaic cell is naturally extended.
In fact, however, it is not easy to make photovoltaic cells thin, which involves a difficult problem of power generation efficiency. Just recently, scientists at the University of Cambridge in the UK have come up with a design for a radiation-resistant photovoltaic cell. The photovoltaic cell is characterized by an ultra-thin layer of light-absorbing material, which can better cope with radiation damage and improve satellite performance.
The cell is known to involve a two-part design, an on-chip design made by stacking several substances in layers, and a design involving a silver mirror to enhance light absorption. And since there is less demand for ultrathin battery cover slips to run for long periods of time, there are significant advantages in other resources such as load costs.
(Source: Daily Science and Technology Daily)
Original title: Making photovoltaic cells thinner to make satellites last longer
