The physical and chemical causes of damage to generator contact rings and brushes

The results of an analysis of the processes occurring at the sliding contact between the brush and contact ring of generators are presented. It is shown that arc and spark discharges are one of the main causes of increased wear on brushes and rings. It is established that arc discharges occur when there are breaks in the brush current circuit while spark discharges occur due to overvoltages in the rotor winding circuit.