HydrogeneratorThe excess of reactive power generated by power transmission lines is the reason for impermissible increase of voltage at the terminals of the length power transmission lines for consumers. One of the alternative decisions for this problem could become at the hydropower station hydrogenerators, specially designed or reconstructed for their possible operation at underexcitation. The problem hydrogenerator’s operation with consume of reactive power from the net is caused, at first, by the stator core end parts heating. The new design of pole end plate with nonmagnetic part is used for the decrease of end parts heating. The experimental and calculation results of the hydrogenerators with new pole design are shown. There are some advantages of the split-design pole end plates using nonmagnetic pole end plates. The reliability, service life and the efficiency of hydrogenerators are increased due to decrease of the heating of the stator core end parts. The possibility of continuous operation of hydrogenerator operation at underexcitation is expanded. It is not necessarily to do the expensive compensating devices.