| Composite insulators are widely used in high-voltage transmission systems due to their advantages such as light weight,high strength,good anti fouling performance and convenient operation and maintenance.At present,the icing problem of composite insulators has not been effectively solved.As a green sustainable passive anti-icing method,photo-thermal coating has become a hot spot of research.However,the study of photo-thermal coatings is still in the phase of optical properties,and it does not explore the physical and chemical properties of insulators,and the discussion on the application of photo-thermal coatings to composite insulators of transmission lines is relatively rare.Therefore,it is of great theoretical and practical value to explore the use of photo-thermal coating and clean energy to solve the icing problem of composite insulators.In this paper,the preparation method of photo-thermal coatings was first proposed,and three kinds of spinel type composite metal oxides were selected to make the photo-thermal coatings with different absorbance pigments and different pigments,and the optical properties and related properties of different photo-thermal coatings were measured.On this basis,a model is established to simulate the icing and ice melting process of composite insulators coated with different photo-thermal coatings under different environmental conditions.Finally,the simulation results are verified by the ice coating and ice melting test,and the best formulation of the photo-thermal coating is determined.The main work and achievements of this paper are as follows:?1?A method for preparing photo-thermal coatings was proposed.In contrast to different light-absorbing substances,Fe,Mn,Cu,Ni,and Cr transition metal elements were selected,and FeMnCuO4,FeNiCuO4,and CuMnCrO4 spinel-type complex metal oxide powders were prepared by a co-precipitation method.Based on RTV silicone rubber,TEOS as crosslinking agent and DBTD as catalyst,a photo-thermal coating containing different pigments and absorbance pigments was prepared.The optical properties and related properties of the photo-thermal coating are measured.The measurement results show that the photo-thermal coating has good photo-thermal properties,hydrophobicity,migration and self cleaning coefficient,and its volume resistivity and relative dielectric constant meet the required insulation requirements.?2?The heat exchange process of photo-thermal composite insulators under icing condition is analyzed.FXBW4-10/100 composite insulators were selected to calculate the critical ice protection power required after coating the photo-thermal coating.The critical solar power density required for ice prevention is obtained and compared with the sunlight illumination under the ice covered weather in winter in China,the anti icing effect of the photo-thermal coating is analyzed.The calculation results show that the photo-thermal coating can not prevent the formation of icing under the environment of icing.?3?COMSOL finite element software was used to simulate the influence of ambient temperature,solar light intensity,type of absorbable pigment and pigment base on the surface temperature rise of composite insulators coated with photo-thermal coating.The results show that the temperature rise rate of ambient temperature,solar light intensity and pigment base ratio is positively correlated with the temperature rise rate of the photo-thermal coating,and the temperature rise rate of the photo-thermal coating with the absorption pigment of FeMnCuO4 is the highest in the case of the same pigment base ratio.?4?In the artificial climate chamber,the insulator icing and ice melting tests were carried out on composite insulators coated with different photo-thermal coatings.The effects of environmental temperature,solar light intensity,type of absorbable pigment and pigment base ratio on the anti/melting ice effect of composite insulators coated with photo-thermal coatings were studied.The test results show that the photo-thermal coating has a certain mitigation effect on the formation of ice coating at the beginning of ice coating,the absorbable pigment is FeMnCuO4,the photo-thermal coating with the pigment base ratio of 40%is the best.With the increase of ice coating time,the photo-thermal coating loses its anti icing effect;The environment temperature,solar light intensity and pigment base ratio are positively related to the melting ice effect of the photo-thermal coating.The low environmental temperature and the light and heat intensity of the coating are weak,the absorbable pigment is FeMnCuO4,and the photo-thermal coating with the pigment base ratio of 40%is the best.Therefore,it is the best formula for the photo-thermal coating. |
PDF Full Text Request