Research On The Ionized Field And Instulator Pollution Of HVDC Transmission Lines Under Haze Weather

The areas where haze activities are higher are also with limited transmission linecorridors and large power load. The performance of overhead transmission lines isunder threat of the haze. The haze particulates around the HVDC transmission lines willbe charged due to the ionized field and the charged haze particulates will affect thecorona and electric field of in the vicinity of HVDC transmission lines. In addition, themovements of the haze particulates will change because of the electric field and theinsulators’ pollution characteristics could be affected.The UHVDC transmission lines will be extended across China. The research of theinfluence of haze on the ionized field and the effect of charged haze particulates oncontamination of transmission equipment are very necessary, especially for those areawith air pollution index goes into300μg/m3(serious pollution) or500μg/m3(hazardous pollution). This paper focus on the influence of the haze on the ionized fieldand contamination of HVDC transmission lines. Firstly, an improved Meshless Methodwhich is more suitable for dealing with ionized field problems has been proposed.Secondly, the charging process of haze particulates and numerical model of ionizedfield in presence of haze has been studied. Based on the numerical model construct bythe improved MLPG method, the distributions of the ground level ionized field inpresence of haze with different temperature has been discussed. At last, the movementcharacteristics of the charged haze particulates in the ionized field has been studied, andthe influence of haze on the contamination of insulator has been studied by experiment.The main innovative points of this thesis are shown as follows:(1) An improved MLPG (Meshless Local Petrov-Galerkin) method is proposed inthis thesis. The improved method uses the RPIMp (radial basis function with additionalpolynomial basis) shape functions and self-adjusted local sub-domain sto overcomethe shortcoming of regular MLPG method. This makes the improved MLPG methodvery easy to deal with irregular or complex geometries. The improved MLPG methodhas been used to calculate the ionized of HVDC transmission lines, the results show thatthe improved MLPG can obtain accurate results in the ionized field problem.(2) Based on the charging process of haze particulates and influence mechanism ofhaze on ionized field, the governing equation of ionized in presence of haze are given inthis thesis. The improved MLPG method are used for the construction of the numerical model, the distribution of the ground level ionized field in presence of haze withdifferent temperature are discussed. The results show that, the haze will increase theground level total electric field, and the maximum value get higher with the pollutionlevel of haze increasing. The calculation results indicated that the ground level electricfield becomes stronger if the haze with higher temperature.(3) The movement characteristics of the charged haze particulates in the ionizedfield has been studied. The charge polarity of charged haze particulates and theinfluence of haze on the contamination of insulator has been studied by experiment.Based on the movement of the charged haze particulates in ionized field and thedynamic commination accumulating of the haze particulate on the HVDC insulator, theinfluence of haze weather on the insulator contamination are given in this thesis.