Simulation Of Temperature Field And Thermal Stress Field With Multi-physics Coupled Method For Dry-type Hollow Shunt Reactor

Dry-type hollow shunt reactors mainly play a role in reactive power compensation in power systems.They have the advantages of simple structure,low loss,strong anti-saturation ability,and easy maintenance.They are used more and more in the system.During the operation of the dry-type hollow shunt reactor,the encapsulation cracking phenomenon may occur due to the influence of local high temperature and other factors.In severe cases,the internal insulation of the encapsulation is damaged,causing a short-circuit between turns,causing the reactor to burn down and affecting the stability of the power system.This paper mainly studies the characteristics of dry-type hollow shunt reactors based on temperature distribution,and discusses the effect of thermal stress on encapsulation cracking.Dry-type hollow shunt reactors mainly play a role in reactive power compensation in power systems.They have the advantages of simple structure,low loss,strong anti-saturation ability,and easy maintenance.They are used more and more in the system.During the operation of the dry-type hollow shunt reactor,the encapsulation cracking phenomenon may occur due to the influence of local high temperature and other factors.In severe cases,the internal insulation of the encapsulation is damaged,causing a short-circuit between turns,causing the reactor to burn down and affecting the stability of the power system.This paper mainlystudies the characteristics of dry-type hollow shunt reactors based on temperature distribution,and discusses the effect of thermal stress on encapsulation cracking.This paper uses simulation software to simulate the temperature field of a BKK-20,000 / 63 dry hollow shunt reactor under different environmental temperatures,different operating voltages and different material characteristics,and continue to interact with the thermal-stress field Coupling,simulation analysis of strain and thermal stress.Before simulating the temperature field of the dry-type hollow shunt reactor,according to the calculation principle of the temperature field,the loss parameters of the dry-type hollow shunt reactor were first calculated,and the heat source intensity was obtained by combining the volume parameters.Due to the huge number of turns in the BKK-20,000 / 63 dry-type hollow shunt reactor model,a three-dimensional flow-temperature field model with the size of the actual reactor was established based on the reasonably simplified envelope structure.Under different temperatures and applied voltages,using simulation software and an iterative calculation method,the temperature field of the dry hollow shunt reactor is obtained.Using analysis software for thermal-stress coupling,under different environmental temperatures,different applied voltages and different material conditions,the strain and thermal stress of the dry-type hollow shunt reactor are simulated and studied.Statistics of the temperature rise variation law,and comparison with the actual measurement data,we can get the following conclusions: under different environments and different operating voltages,the temperature distribution law of the dry-type hollow shunt reactor is basically unchanged,and the hottest temperature appears in 80% ? 90% At the height position,the temperature difference is significant;as the ambient temperature changes,the average temperature rise and themaximum temperature rise in a linear proportional change;as the operating voltage increases,the average temperature rise and the maximum temperature rise of each envelope of the dry-type hollow shunt reactor increase.Statistic the variation law of strain and thermal stress,we can get the following conclusions: under various conditions,the thermal stress on the envelope is the largest in the axial direction;when the ambient temperature is high,the strain and thermal stress on the upper part of the reactor are large,and the ambient temperature is low At the time,the strain and thermal stress in the lower part of the reactor are large;at room temperature,the encapsulation strain and stress increase with the increase of the operating voltage;under the same material,the thermal stress is very small,and the thermal stress increases significantly as the material difference increases.The research results show that the axial thermal stress on the encapsulation is relatively large.If measures such as reducing the temperature rise of the reactor or increasing the encapsulation insulation strength are not taken,the encapsulation insulation will be cracked.This paper can provide a basis for exploring the encapsulation cracking mechanism of the reactor.