Computer assisted design of impulse voltage dividers

A new method for the design of EHV dividers is presented, which not only permits the calculation of their optimum geometry but also gives the divider response time. The electric field distribution around the divider is calculated using a new computer program based on a charge simulation technique. The response time is then derived from the distribution of the normal component of the field along the divider resistive elements. The method presented has been applied to the design of a 2.5 MV resistive divider and the calculated response time as well as the corona onset voltage level agree with the measured ones. The relation between the divider linearity with voltage and the maximum field gradients is discussed and certain values of this design parameter are proposed.