Assistant, Karshi engineering-economics institute, Uzbekistan, Karshi
Temperature connection of volt-amper characteristics of solar elements
Almost 100% of the energy we use in our daily lives is solar energy that is modified in one way or another. Coal is a dead plant that lives through photosynthesis. Even if you provide the solar energy that the wood absorbs, In fact, any thermal power plant converts solar energy into electricity, which is stored in the form of coal, oil, gas and other minerals.
Почти 100% энергии, которую мы используем в нашей повседневной жизни, - это солнечная энергия, которая так или иначе видоизменяется. Уголь - это мертвое растение, которое переживает фотосинтез. Даже если вы обеспечиваете солнечную энергию, которую поглощает древесина, на самом деле любая тепловая электростанция преобразует солнечную энергию в электричество, которое хранится в виде угля, нефти, газа и других полезных ископаемых.
Keywords: Solar, energy, silicon, renewable energy germanium, semiconductor.
Ключевые слова: Солнце, энергия, кремний, возобновляемые источники энергии, германий, полупроводник.
Currently, one of the processes in the world to combat global environmental problems is the use of energy sources for renewal. Such sources make good use of the most promising solar energy as an active heat source as well as a photoelectric energy source [1-5].
The electrophysical properties of photoelectric panels are largely determined by the properties of the photocells they contain. In turn, the voltammetric characteristics of solar cells and the power related to VAC (Volt ampere characteristic) depend on the operating temperature of the photocell, so by studying the macroscopic properties of solar cells, the processes occurring in photoelectric panels It is possible to have an idea [1-16].
Figure 1. Device diagram to complete the experimental process
It is known that the volt-ampere characteristic VAC (Volt ampere characteristic) in the illumination of SE (Solar elements) are determined from the following expression.
It is not possible to explain the temperature dependence of the experimentally determined VAC by calculations using VAC. This is because we first need to determine the effect of temperature on the short-circuit current density and saturation current density in (1). It is known that in SE (Solar Elements) illumination, the photocurrent density is zero when the output voltage at VAC is equal to the operating voltage (Usi). Therefore, given U = Usi and jf= 0 in (1), the following equation holds:
It can be seen from this expression that in order to determine the temperature dependence of the short-circuit current density of QE (solar elements)’s, it would be necessary to determine whether their saturation current density and the salting operating voltage are temperature-dependent. In this case, according to the results of experiments for the temperature dependence of the operating voltage, the following expression for this parameter can be obtained by extrapolating T = 0 K empirically:
From this expression, it can be seen that in order to determine the temperature dependence of the short-circuit current density of QE (solar elements), it is necessary to determine their temperature dependence of the saturation current density and the voltage. In this case, according to the experimental results for the temperature dependence of the operating voltage, the following expression for this parameter can be obtained by extrapolating T = 0 K empirically [1-6]:
where Usi0 – To = 300 K daisalt operating voltage, φ is the potential barrier height of SE (solar element), and the temperature dependence of this parameter is the same as the temperature dependence of the band gap of semiconductors [4,5,6,10]:
-- The ambient zone of amorphous semiconductors is the temperature coefficient of energy width, which is in the range of 5 10-4 - 10-5) eV / K. The following expressions are given in the literature for saturation current density:
The numerical value of these parameters for the SE (Solar element) under study cannot be determined directly from VAC. Therefore, we first determine the temperature dependence of the saturation current density in the following figure. Assuming that the saturation current density is jo= j00 when T0 = 300 K, then we get
Substituting (5) for (6), we obtain the following expression for the saturation current density:
Substituting (3), (4) and (7) into (2), we obtain the following equation to relate the short-circuit current density SE (solar element) to temperature:
Let us now turn to the definition of the expression that explains the effect of temperature on VAC in the illumination of SE. Taking into account (7) and (8), we obtain from (1):
The literature shows that the non-ideal coefficient of SE is practically independent of temperature. Therefore, (9) can be used to describe the effect of temperature on sevac.
Figure 2. VAC’s of amorphous silicon-based SEs at temperatures of 214 K and 293 K.1 Experiment and calculation results from formula 2- (9).
As shown in Figure 2, the results of experiments and calculations are consistent at high and low voltages. However, there is a non-significant difference between these results near the VAC Volt Ampere characteristics) effective power points. In our view, at the point of view of VAC (Volt Ampere characteristics), the photocurrent generated in SE (Solar Element) changes strongly relative to the other area of the curve.
It is known that the value of the non-ideal coefficient of a diode determines the nature of the electric current passing through it. It should be noted that in order to match the calculation and experimental results, the value of the non-ideal coefficient of QE VAC had to be selected as follows: n1 =1.0034 at T1 =214K, n2 = 1.0061 at T2 =293K. The difference between n1 and n2 is not so great. Therefore, this difference should be considered within the limits of experimental error.
- Muradov I., Toshmamatov B.M. Kurbanova N.M., Baratova S.R., Temirova L. Development of A Scheme For The Thermal Processing of Solid Household. International Journal of Advanced Research in Science, Engineering and Technology Vol. 6, Issue 9, September 2019, India, PP. 10784 10787.
- Sychov, A., Kharchenko, V., Vasant, P., Uzakov, G. Application of Various Computer Tools for the Optimization of the Heat Pump Heating Systems with Extraction of Low-Grade Heat from Surface Watercourses. Advances in Intelligent Systems and Computing, 2019, 866, PP. 310–319.
- Gulom Norboevich Uzakov, Lola Abdujabborovna Aliyarova, Khayrullo Allamurotovich Davlonov, Bobir Mansurovich Toshmamatov. The use of solar energy in systems of heat-moisture treatment of air of heliogreenhouse. International Journal of Mechanical and Production Engineering Research and Development. 2020/1 №10, PP 3813-3820.
- B.M. Toshmamatov, G.N. Uzakov, S.M. Shomuratova, L.Z Temirova. Calculation of Energy Efficiency of the Solar Installation for the Processing of municipal Solid Waste. International Journal of Advanced Research in Science, Engineering and Technology. 2019/12 PP. 12097-12102.
- Uzakov G.N., Toshmamatov B.M., Kodirov I.N., Shomuratova S.M. On the efficiency of using solar energy for the thermal processing of municipal solid waste. Journal of critical reviews. ISSN- 2394-5125 VOL 7, ISSUE 05, 2020.
- Saydulla Mirzaevich Khujakulov, Gulom Norboevich Uzakov. Research of thermo moisten mode inunderground vegetable storehouses in the conditions of hot-arid climate. European science review. 2017, №11-12. PP-164-166.
- Узаков Г.Н. Исследование тепломассообменных процессов и теплохладоснабжения в плодоовощехранилищах. Краснодар, КубГАУ. 2006.
- A Sychov, V Kharchenko, P Vasant, G Uzakov. Application of various computer tools for the optimization of the heat pump heating systems with extraction of low-grade heat from surface watercourses. International Conference on Intelligent Computing & Optimization. 2018/10/4. PP 310-319.
- Г.Н. Узаков, А.Т. Теймурханов, А.Б. Вардияшвили, Р.А. Захидов. Исследование теплофизических характеристик картофеля при длительном хранении в малом хранилище. Хранение и переработка сельхозсырья. 1999. №2 59-57.
- Khujakulov S.M., Uzakov G.N., Vardiyashvili A.B., Effectiveness of solar heating systems for the regeneration of adsorbents in recessed fruit and vegetable storages. //Applied Solar Energy. – USA, vol.49, № 4. pp. 257-260, 2013.(05.00.00. №4. Scopus CiteScore 2018, IF:0.9).
- Uzakov G.N., Khujakulov S.M., Investigation of the temperature conditions of a solar-air heating installation for systems for the thermal regeneration of adsorbents. // Solar technology. - No. 1.pp. 40-43, 2017, (05.00.00.No. 1).
- Uzakov G.N., Davlonov Kh.A., Holikov K.N., Study of the Influence of the Source Biomass Moisture Content on Pyrolysis Parameters// Applied Solar Energy, Vol. 54, No. 6, pp, 481-484. 2018, (05.00.00; №4. Scopus CiteScore 2018, IF:0.9).
- Toshmamatov B., Davlonov Kh., Rakhmatov O., Toshboev A. Recycling of municipal solid waste using solar energy. IOP Conf. Series: Materials Science and Engineering. 1030 (2021) 012165. doi:10.1088/1757-899X/1030/1/012165.
- Aliyarova L.A., Uzakov G.N., Toshmamatov B.M. The efficiency of using a combined solar plant for the heat and humidity treatment of air. IOP Conf. Series: Earth and Environmental Science. 723 (2021) 052002. doi:10.1088/1755-1315/723/5/052002.
- G N Uzakov, S M Shomuratova and B M Toshmamatov. Study of a solar air heater with a heat exchanger – accumulator. IOP Conf. Series: Earth and Environmental Science. 723 (2021) 052013. doi:10.1088/1755-1315/723/5/052013.
- T A Faiziev and B M Toshmamatov. Mathematical model of heat accumulation in the substrate and ground of a heliogreenhouse. IOP Conf. Series: Earth and Environmental Science. 723 (2021) 032006. doi:10.1088/1755-1315/723/3/032006.