Silniki wysokiego napięcia dla trudnych warunków eksploatacyjnych. (Projektowanie i wykonawstwo)

High voltage (6000 and 10000 V) AC squirrel cage motors are started by switching direct on line. The inrush of starting current causes mechanical and thermal stresses in the motor structure, mainly in their rotor's cage. Motors for hard working conditions, esp. for high frequency of starts, or for long lasting starts should be designed and manufactured especially. At Komel Centre several calculation and designing methods for motors exploited at hard working and starting conditions were elaborated. Many motors of this kind were designed by Komel and manufactured by polish manufacturers. The motors were exploited several years in various branches of industry without any breakdowns. In the paper three cause studies are presented: 550, 800, and 2000 kW motors, where redesigning and replacing only their rotors were full satisfactory.