| The slip-ring is the structure responsible for the transmission of electrical signals and power in the Solar Array Drive Assembly.Its function is realized through the contact sliding between the slip ring in the slip-ring and the electric brush.In the contact friction process,it is inevitable to produce abrasive particles due to friction and wear.The abrasive particles are in contact with electric charge and move under the action of electromagnetic field.The adhesion deposition of the debris particles in some positions of the slip-ring after movement migration may cause electric field distortion,which will induce discharge and affect the normal power transmission of the Solar Array Drive Assembly.In this paper,the electromagnetic field distribution inside the Solar Array Drive Assembly and the movement and migration characteristics of particles with electric abrasive particles are studied by combining experimental research and simulation.The specific research work and conclusions are as follows:?1?Experimental study on the charge status and morphology characteristics of abrasive particles in the slip-ringThrough the detection and observation of abrasive particles samples,the abrasive particles generated in the slip-ring are in the shape of thin sheets,with the overall appearance of loose accumulation,mainly from the electric brush part of the slip-ring.At the same time,the electrification of abrasive particles was investigated by using the experimental device of parallel plates.The experimental results show that the abrasive particles generated in the slip-ring are charged and have a positive charge.?2?Research on electromagnetic field simulation model of Solar Array Drive AssemblyBased on the COMSOL Multiphysics platform,the electromagnetic field simulation model of the Solar Array Drive Assembly under normal working conditions was established by using the interface between the magnetic field and the electric field in the AC/DC module of the platform.The simulation models are divided into two types:the overall structure of the conducting ring and the 1/4 structure of the conducting ring.By comparing the electromagnetic field simulation results of the two structures,it is concluded that the electromagnetic field calculation results of the two structures are basically the same.Therefore,the structure of the slip-ring is simplified to a quarter structure.?3?Study on the influence of charge-discharge effect on the electric field inside the conducting ringIn this chapter,through the coupling calculation between the particle tracking interface and the electrostatic interface in the AC/DC module of COMSOL Multiphysics platform,the variation of the electromagnetic field distribution characteristics of the slip-ring inside SADA is analyzed when high-energy particles are incident on SADA.The charge and discharge effect will increase the maximum electric field intensity E inside the conducting ring from 2.6542×104V/m to 2.0081×106V/m,and the maximum current density from 7.1375×107A/m2 to 7.2707×107A/m2.The charge and discharge effect has obvious influence on electric field,but has little influence on current density.Therefore,the charging characteristic will not affect the stable transmission of current and electric signal to a great extent.?4?Study on the movement and migration of electromagnetic field and abrasive particles in the conducting ringOn the basis of COMSOL Multiphysics platform,the electromagnetic field distribution in the slip-ring and the movement and migration of abrasive particles were simulated and calculated.The simulation results show that the electromagnetic field near the outer slip ring of the slip-ring is relatively strong.Under the action of electromagnetic field,98%of the abrasive particles in the conductive ring move on the surface of the shield shell,and the rest are scattered in the conductive ring,with a velocity change of about 10-3orders of magnitude. |
PDF Full Text Request