Research On Flushing Characteristics Of Electrified Insulators Under Eccentric Flushing Conditions

With the continuous development of industrial development,electric power has become an indispensable energy source for today’s society,which constitutes the basis of people’s daily life and industrial production,and is also an essential prerequisite for economic development.At the same time,the rapid development of industry and agriculture has led to an increase in the types and density of pollutants in the air.The suspended particles in the air are continuously settled in the externally insulated electrical equipment,which reduces the insulation performance,which is very likely to cause a flash over accident,which seriously affects the normal operation of the power supply.The ever-larger grid scale puts higher demands on the sustainability and reliability of electric power,and it is also important to maintain the maintenance of electrical equipment.Insulators are the most widely used externally insulated electrical components in power supply systems,so it is very important to keep its surface cleaning.1.The composition of the contamination layer attached to the surface of the insulator was analyzed.The main contamination on the insulator was that the particle size was 20μm and the main components were CaSO₄ and SiO₂ particles.Based on the JKR particle adhesion model,the adhesion model of contamination on the insulator wall is simplified.By analyzing and calculating the adsorption and desorption mechanism of the insulator contamination,the critical shear rates required for the rolling desorption and sliding desorption of the contaminated particles are 3860s^-11 and 51710s^-1.When rinsing,the particles are more easily removed by rolling and desorption.2.Fluent is used to simulate the flushing operation of different horizontal deflection angles in three flushing modes:small water,medium water and large water.The critical horizontal deflection angle is analyzed according to the change of the striking force.Through the curve fitting of the simulation results by matlab,the critical horizontal deflection angle under the premise of ensuring the striking force is obtained,and the critical horizontal deflection angle is compared under various working conditions.The critical deflection angle decreases with the increase of the inlet pressure.The rate of change increases as the diameter of the nozzle increases.When the inlet pressure is the same,the critical deflection angle decreases as the diameter of the nozzle increases.The striking force of the water jet on the insulator wall increases as the inlet pressure increases.And as the diameter of the nozzle increases,the rate of increase of the striking force with the inlet pressure also increases.When the inlet pressure is the same,the striking force increases as the diameter of the spout increases.According to the polynomial of the critical horizontal deflection angle with respect to the inlet pressure and the nozzle diameter,the critical deflection angle of the pressure at 1-4 MPa and the nozzle diameter of 3-8 mm can be calculated.When the horizontal deflection angle exceeds the critical flush angle,the striking force drops sharply.In order to ensure the effect of flushing,the horizontal deflection angle should be kept within the critical deflection angle during actual operation.3.Under the small water and medium water flushing mode,the effective flushing area increases with the increase of the inlet pressure,but its growth rate decreases with the increase of pressure.When the inlet pressure is constant,as the horizontal deflection angle increases,the effective flushing area on the lower surface of the insulator shed increases.The reduction of the effective rinsing area on the upper surface of the insulator shed and the inner disc column flushed by the water jet rotary water and the sputtered water increases,thereby causing the total area of the effective rinsing to increase first and then decrease.When the water is rinsed with large water rinsing,the effective rinsing area on the lower surface of the insulator shed will be saturated,resulting in a continuous decrease in the effective rinsing area as the horizontal deflection angle increases.In order to improve the cleaning efficiency of the lower surface of the insulator shed during the rinsing operation,the horizontal deflection angle should be appropriately increased.