SIMULATION OF LOW-FREQUENCY FIELDS ON HIGH-VOLTAGE INSULATORS LIGHT CONTAMINATIONS

This paper deals with the numerical solution of the linear complex Poi sson equation. The practical background of posing this problem are are -overs on moist or contaminated insulators in high-voltage power plant s. The electrostatic field of the charge-free space prevails essential ly below a critical voltage Uk However, the dielectric material looses its insulating characteristics above Uk. It becomes the carrier of a discharge which builds up a conducting connection along the insulator. It is a matter of slowly varying fields (50 Hz), for which the displa cement current is a significant quantity. These slowly varying fields can be determined by solving a complex potential problem. Discretizati on leads to a complex system of linear equations with symmetric matrix . This system is solved by various modern conjugate gradient-type meth ods. Numerical simulations for test and real life problems are present ed.