A practical mathematical model of corona for calculation of transients on transmission lines

A practical mathematical model of the corona effect on overhead power line transients is developed based on the concept of time delay in corona formation. Results computed by this model agree well with experimental q-v (charge-voltage) characteristics for both fast and slow impulse voltages under both polarities. It is shown that the introduction of the time-delay concept leads to better results and a better understanding of many important characteristics of q -v curves, especially for fast transient voltages. The model is applicable to transmission lines with either known or unknown q-V characteristics because all the model parameters can be determined beforehand according to the conditions of the line