1、 Photovoltaic System Design 1 Introduction After PV workers unremitting efforts, solar cell production technology constantly improve, and increasingly widely used in various fields. Posts and telecommunications in particular, the telecommunications industry in recent years because of the rapid devel
2、opment of communication power requirements have become more sophisticated, so stable and reliable power Solar energy is widely used in communications. And how the various regions of solar radiation conditions, to the design of both economic and reliable photovoltaic power system, which is one of the
3、 many experts and scholars study the long-standing issue, but there are many excellent research results, for the development of Chinas photovoltaic laid a solid foundation. The author of the study at the design methodology of experts found that the design has only considered the self-maintenance of
4、battery time (that is, the longest consecutive rainy days), without taking into account the loss of electric batteries as soon as possible after the recovery time (ie, two sets of the longest continuous rain days, the shortest interval between the days). This problem particularly in the southern Chi
5、na region should pay great attention to the southern region because of our rainy day is long too, and for the convenience of independent photovoltaic power system, because there is no other emergency backup power protection, so this problem should be included in the design considered together. In th
6、is paper, an integrated design method of the previous advantages, combined with the author over the years actually engaged in the design of photovoltaic power systems experience, the introduction of two sets of the longest consecutive rainy days, the shortest interval between the number of days as t
7、he basis for the design of one, and comprehensive consideration of the the impact of solar radiation conditions of the factors that made solar cells, the formula for calculating battery capacity, and related design methods. 2 Many factors affect the design Sun solar cells on the ground square on the
8、 radiation of light spectrum, light intensity by the thickness of the atmosphere (ie air quality), geographic location, the location of the climate and weather, terrain and surface features such as the impact of its energy in one day, January and a year of great change, or even years between the tot
9、al annual amount of radiation There were also large differences. Square solar photoelectric conversion efficiency, by the battery itself, temperature, sunlight intensity and battery voltage fluctuations, which is three in one day will change, so square photovoltaic solar cell conversion efficiency i
10、s also variable. Battery is charging in the float state, with the square of its voltage output and load power consumption changes. Batteries to provide energy is also affected by environmental temperature. Solar energy battery charge and discharge controller made by the electronic components manufac
11、turer, it is also necessary energy, while the use of components of performance, quality, etc. is also related to the size of energy consumption, thus affecting the efficiency of charge. Load of electricity, but also as determined by uses, such as communications relay stations, unmanned weather stati
12、ons and so on, have a fixed power equipment. Some equipment such as a lighthouse, beacon lights, civilian power consumption such as lighting and equipment power consumption are often changing. Therefore, the solar power system design, the need to consider many factors and complex. Characteristics ar
13、e: the data used in most previous statistical data, the statistical data measurement and data selection are important. Designers of the mission are: In the solar cell matrix under the conditions of the environment (that is, the scene of the geographical location, solar radiation, climate, weather, t
14、errain and surface features, etc.), the design of solar cell and battery power system matrix is We should pay attention to economic efficiency, but also to ensure system reliability. Location of a particular energy of solar radiation data to meteorological information provided the basis for the desi
15、gn of solar cells used phalanx. These meteorological data required to check the accumulation of several years or even decades on average. Various regions on the Earth by sunlight and radiation changes in the cycle for the day, 24h. In a square area of solar cells also have the power output 24h of th
16、e cyclical changes in its laws and sun radiation in the region, the changes of the same. However, changes in weather will affect the square of the generating capacity. If you have a few days consecutive rain days, almost square on the power generation should not rely on batteries to power, and batte
17、ry depth of discharge and then need to be added as soon as possible good. Most designers in order to weather the sun to provide a daily total of radiation energy or the annual average sunshine hours as the design of the main data. Each year because of a regional data is not the same as for the sake
18、of reliability should be taken within the last decade of the minimum data. Under the load of electricity consumption, in sunshine and no sunshine when battery power is required. Weather provided by solar power or the total amount of radiation the total sunshine hours on the battery capacity of the s
19、ize of the decision is indispensable data. Phalanx of the solar cell, the load should include all power system devices (except for use but also have a battery and electrical circuits, controllers, etc.) consumption. Matrix components of the output power and the number of series-parallel, and series
20、are required in order to obtain the operating voltage, in parallel are necessary in order to obtain the current work, an appropriate number of components through which the composition of series-parallel connection of solar cells required phalanx. 3 Designed capacity of batteries Solar cell power sup
21、ply system is the battery energy storage devices. And solar cell batteries are usually square matching job at Floating state, with the square of its voltage output and load power consumption changes. Its load capacity than the power required is much greater. Batteries to provide energy is also affec
22、ted by environmental temperature. And solar cells in order to match the job requirements of long life battery and easy maintenance. (1)Battery Selection And be able to support the use of solar cells, many different types of batteries, widely used at present have lead-acid maintenance-free batteries,
23、 ordinary lead-acid batteries and alkaline nickel-cadmium batteries of three. Domestic use are mainly maintenance-free lead-acid batteries, because of its inherent free maintenance of properties and less polluting to the environment characteristics, it is suitable for the performance of reliable pow
24、er systems solar power, especially in unattended workstations. Ordinary lead-acid batteries require regular maintenance because of its larger environmental pollution, so the main suitable for the maintenance of the ability or have the use of low-grade occasions. Although alkaline nickel-cadmium batteries have better low-temperature, over-charge, take-off performance, but because of their higher prices, only applies to more special occasions. (2)Calculation of battery capacity
