Evaluation of the electric field at the surface of a conductor

which is well described by the Poisson equation

is of great importance on many occasions in power systems. This paper proposes a collocation boundary element method where the unknown surface charge density function is assumed to be either azimuth independent or dependent. Detailed formulas

including the quadrature rules and how to accelerate the computation when the target point lies far away from the integral element

are proposed. Numerical examples are shown to confirm the convergence of the method

and manifest the great advantage for the evaluation of the electric field around slender conductors.