Temperature Rise Simulation of Medium Voltage Cubicle Type Gas Insulated Switch-Gear Based on Coupling of Multi-Physical Fields

Abstract

Usage of Cubicle type Gas-Insulator Switch-gear (C-GIS) is gradually increasing in power system. During the operation of C-GIS, long-term excessive temperature rise leads to degeneration of insulation and mechanical property, which may finally leads to fatal accidents. In order to analyze the temperature distribution of the C-GIS, the model of a 40.5 kV medium voltage SF 6 insulated C-GIS has been established and simulations based on electromagnetic-fluid-temperature coupling are carried out. In the simulations, eddy-current filed is solved by ansys-multiphysics to obtain the heat generation inside the C-GIS. In order to improve calculation accuracy, the contact resistance is taken into consideration and the physical characteristics of SF 6 gas are considered to be related to the temperature. First, simulations with and without surrounding air environment considered are carried out and the results are compared. The type test of temperature rise is also conducted to verify the simulation results. The simulation results are found out in agreement with experimental results. Second, in order to reduce the temperature rise and improve the design of C-GIS, recommendations are put forward. The influence of the cooling system and surrounding barriers is analyzed by numerical simulation.INDEX TERMS Temperature rise simulation, cubicle type gas insulated switch-gear, multi-physical fields.

An innovative method to conduct temperature rise test on medium voltage switchgear assembly based on IEC standards in a power grid

“…Temperature rise test is one of the type test performed on almost all electrical equipment to verify the over load capacity of the equipment and to study the performance of the equipment under thermal and mechanical stress [10][11][12][13]. Temperature rise test helps to get perusal of energy loss that occurs in the equipment during its operative condition.…”

“…Temperature rise test helps to get perusal of energy loss that occurs in the equipment during its operative condition. The temperature rise that occurs in the current carrying parts of the equipment is because of the resistive nature that is present in the conductor; the rise directly depends on the resistivity of the conductor [12,14]. The actual lifetime of power electrical equipment, or their ability to operate without failure, is highly dependent on their mode of operation and service conditions.…”

“…Temperature increase limitations must be strictly adhered to as prescribed by the referenced standard. This is due to the fact that failure to comply with the specification will result in a switchgear failure [12].…”

Precise multi‐dimensional temperature‐rise characterisation of switchgear based on multi‐conditional experiments and LPTN model for high‐capacity application

“…According to formula (9), factors affecting convective heat dissipation are the contact area and coefficient of heat convection. Since the area is hard to change in switchgear, methods are taken to change the coefficient of heat convection by opening and closing the fans.…”

“…The modelling approaches are mainly numerical method and the lumped-parameter thermal network (LPTN) method [5]. Numerical methods, known as computational fluid dynamics and finite element method are used to solve and analyse the coupling problems [6][7][8][9][10]. The main strength of numerical analysis method is that any complex geometry can be modelled in simulation software after some simplification.…”