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Analysis of Mechanical Stress during Short Circuit in an Air-Insulated MV Switchgear
Bártů, Jan ; Bajánek, Tomáš (referee) ; Orságová, Jaroslava (advisor)
This Master thesis is based on problems of force effects of the magnetic field of short-circuit current. Firstly, I analysed the force action of the three phase busbars during the three-pole short circuit. The analysis was performed in the Ansys Maxwell program and I verified the correctness of the analysis by numerical calculation. The second practical part was executed for ABB company. The main task was to analyse the force effects of the short-circuit current in the HV switchgear with focusing on the arms and contact system of the circuit breaker. The simulations of the following configurations were performed in more details: three configurations of the simplified VD4 circuit breaker, two types of VD4 circuit-breaker contact systems and a linear circuit breaker configuration model. The objective was to calculate the forces acting on the current path of the arms and contact system of the VD4 circuit breaker during the three-phase short-circuit and to simulate the effects of forces on these current parts. For modelling of individual assemblies, calculations and simulations I used: SolidWorks 2014, Ansys Maxwell 16.0 and Ansys Workbench 14.5 programs. With SolidWorks 2014 3D CAD software were modelled simplified assemblies of circuit breakers and contact systems. These systems were imported into the Ansys Maxwell software, where the force effects of the magnetic field of the short-circuit current were calculated. In Ansys Workbench programme was simulated the effect of forces on the current circuit breakers. Moreover, the final deformations of the materials (with respect to the mechanical properties of the structure) were plotted. The analysis of force effects of the magnetic field was performed for the specified static short - circuit current value.
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Short - circuit conditions at Sokolnice 110 kV switching station following a direct 400/110 kV transformation
Hajdú, Lukáš ; Paar, Martin (referee) ; Blažek, Vladimír (advisor)
The goal of this bachelor´s thesis is to evaluate short-circuit conditions at the Sokolnice 110kV switching station before and after installation of a T402 transformer – before and after application of a direct 400/110kV transformation. By evaluating these conditions determine whether the originally installed protective elements (power circuit-breakers) are capable of fulfilling the new short-circuit requirements at the switching station. The thesis consists of two parts: the first part introduces the theory required to evaluate the short-circuit conditions at the switching station, while the second part calculates the actual short-circuit currents and power outputs. The methods used for calculation are sequential simplification and symmetrical components.
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Analysis of Mechanical Stress during Short Circuit in an Air-Insulated MV Switchgear
Bártů, Jan ; Bajánek, Tomáš (referee) ; Orságová, Jaroslava (advisor)
This Master thesis is based on problems of force effects of the magnetic field of short-circuit current. Firstly, I analysed the force action of the three phase busbars during the three-pole short circuit. The analysis was performed in the Ansys Maxwell program and I verified the correctness of the analysis by numerical calculation. The second practical part was executed for ABB company. The main task was to analyse the force effects of the short-circuit current in the HV switchgear with focusing on the arms and contact system of the circuit breaker. The simulations of the following configurations were performed in more details: three configurations of the simplified VD4 circuit breaker, two types of VD4 circuit-breaker contact systems and a linear circuit breaker configuration model. The objective was to calculate the forces acting on the current path of the arms and contact system of the VD4 circuit breaker during the three-phase short-circuit and to simulate the effects of forces on these current parts. For modelling of individual assemblies, calculations and simulations I used: SolidWorks 2014, Ansys Maxwell 16.0 and Ansys Workbench 14.5 programs. With SolidWorks 2014 3D CAD software were modelled simplified assemblies of circuit breakers and contact systems. These systems were imported into the Ansys Maxwell software, where the force effects of the magnetic field of the short-circuit current were calculated. In Ansys Workbench programme was simulated the effect of forces on the current circuit breakers. Moreover, the final deformations of the materials (with respect to the mechanical properties of the structure) were plotted. The analysis of force effects of the magnetic field was performed for the specified static short - circuit current value.
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Short - circuit conditions at Sokolnice 110 kV switching station following a direct 400/110 kV transformation
Hajdú, Lukáš ; Paar, Martin (referee) ; Blažek, Vladimír (advisor)
The goal of this bachelor´s thesis is to evaluate short-circuit conditions at the Sokolnice 110kV switching station before and after installation of a T402 transformer – before and after application of a direct 400/110kV transformation. By evaluating these conditions determine whether the originally installed protective elements (power circuit-breakers) are capable of fulfilling the new short-circuit requirements at the switching station. The thesis consists of two parts: the first part introduces the theory required to evaluate the short-circuit conditions at the switching station, while the second part calculates the actual short-circuit currents and power outputs. The methods used for calculation are sequential simplification and symmetrical components.
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