Simulation and verification of Thomson actuator systems
Speaker: Ara Bissal
Time: Fri 2010-06-18 10.00 - 12.00
Location: Hall D3
Supervisor: Göran Engdahl
The Thomson coil’s (TC) inherent characteristics are appropriate to meet the needs of high speed actuators for mechanical switching devices in so-called smart grids. This is due to the massive forces that a TC can exert in the time scale of milliseconds. The scope of this Master thesis work is to build up a working model of a TC by using finite elements based software and explore its features. The approach was to start with simplified models and gradually go into more complicated ones.
Static and stationary models were carried out to study the behaviour and characteristics of a TC at different frequencies. To determine the frequency range of operation and test the possibilities of using an equivalent frequency, Fourier analysis was implemented. Moreover, transient and time dependent models were used to get an accurate estimate of the behaviour of a realistic TC. These models consist of a lumped element method and a multi-physics finite element transient model.
Once the modelling phase was completed, the model was validated experimentally. The results show that the developed model can be used to accurately predict the performance of high speed actuators.
Subsequently, different case studies were explored to better understand the variables involved and their degree of influence they have on the TC. The studied variables were: the TC design, aluminium disk geometry, coil conductor cross-section and number of coil turns. Moreover, the use of flux concentrators was investigated to determine if they can be used to boost performance and efficiency. In this way, the behaviour of the flux lines and their contribution to the exerted force on the aluminium disk were analyzed; thus paving a way for future optimization and improved designs. Once a better TC design was attained, a new prototype was built and tested in a lab to verify the predictions of the simulated model of the new and improved design.