Electrostatic modeling of power transmission lines using boundary element methods
Open Access
- Author:
- Jiang, Yifan
- Area of Honors:
- Electrical Engineering
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Jeffrey Scott Mayer, Thesis Supervisor
John Douglas Mitchell, Thesis Honors Advisor - Keywords:
- Boundary Element Method
Fourier series
Two-dimensional Potential Problems
Charge Distribution of Power Lines
Self-potential - Abstract:
- The electric field at the surface of a power transmission line is an important consideration in the design of the line, as it is related to the capacitance of the line and to the possible onset of corona. Historically, the electric field has been calculated using a model that is known to produce results with a small error but that is very simple to evaluate, even manually. With growing interest in compact high-power lines, for which even small errors are concern, and the availability of low-cost computing, it seems logical to develop more accurate models for the electric field surrounding overhead power transmission lines. Boundary element methods (BEMs) are well suited for this purpose, as the surrounding media is homogeneous and the length scale ratio between the separation and radius of the conductors is very large. Conventional BEMs that rely on a geometric discretization of boundaries into elements would be usable, but two alternatives are considered in this thesis. The first alternative is very simple to formulate but sacrifices accuracy (it is still more accurate than the standard model). It is based on approximating the affect of each element as if the element was reduced to a point source. The second alternative is more complicated to formulate but provides an excellent trade-off between accuracy and computational requirements. It is based on a Fourier series or modal discretization of the boundary instead of a geometric one. The accuracy of the two alternative methods is demonstrated using a two-conductor case for which an analytical solution is known. The Fourier series method is then applied to two practical problems: determining the capacitance of a cable and the electric field of a high-voltage power transmission line with bundled conductors.