| Solar cells are capable of absorbing approximately 80%of the solar irradiance,depending on the photovoltaic effect of the panel material,where a certain proportion of the radiation is converted into electrical energy.However,the remaining energy can dangerously increase the temperature of the silicon junction in the battery package,resulting in performance degradation.It is generally believed that the temperature rise of solar cells is one of the most critical issues for severely reducing and shortening battery life,so thermal management of photovoltaic modules during operation is essential.It is generally believed that a hybrid solar power system design capable of generating electrical energy while utilizing waste heat is the most promising solution to the above problems.In this paper,a solar temperature difference power generation system using heat pipe heat conduction and bismuth telluride material as thermoelectric generator is studied.The system is an integrated structure of photovoltaic cells and temperature difference batteries.The temperature difference battery consists of two identical integrated temperature difference power generation structures.In series,the thermoelectric battery uses the thermal energy of the photovoltaic cell to generate electricity,and the design aims to improve the thermal management of the photovoltaic module and improve the utilization of solar energy.Bi2Te3 is the most commonly used thermoelectric material with the highest thermoelectric value at room temperature.In this paper,an integrated thermoelectric power generation structure is designed by using small ingot P-type and N-type Bi2Te3materials.The structure consists of multiple pairs of thermocouples.In series,a temperature difference of 10°C at normal temperature can generate a voltage of about154 mV.In view of the excellent thermal conductivity and uniform temperature characteristics of the heat pipe,the heat pipe in this paper is used to continuously transfer the heat source of the photovoltaic cell to the thermoelectric power generation structure for power generation,and use the solar thermal energy to generate electricity while cooling the photovoltaic cell.It was found that after 30 minutes of irradiation in the light intensity range of 95.6 W/m2 to 266.2 W/m2,the photovoltaic cells in the structure were more independent than the photovoltaic cells,and the upper surface temperature dropped by 7°C10.7°C,and the lower surface temperature dropped.8.6°C12.4°C,while the efficiency of photovoltaic cells has also increased by 0.43%0.5%,which shows the importance of heat pipe in the structure for the performance and safety of photovoltaic cells.In order to study the performance of solar thermal power generation system,the test platform of the system was designed and a series of tests were carried out.The system was irradiated for 30 min under 5 different light intensities such as 95.6W/m2,134.6W/m2,175.4W/m2,223.2W/m2,266.2W/m2,and the maximum power of the temperature difference battery in the system was 2.18mW,2.55mW,2.62mW,2.80mW,3.32mW,compared with independent photovoltaic cells,the efficiency of the system is 1.39%,1.22%,1.03%,0.93%,1.01%,respectively.Considering that the output of the photovoltaic cell and the temperature difference battery in the system does not match,the conversion output circuit of the system is designed to convert two different output voltages to the same common voltage output,so that the system can be more easily applied to practical situations.This circuit stabilizes the system output at 1.8V,but the system energy is slightly lost. |
PDF Full Text Request