Addressing Reduced Ingress Protection Class & Proper Filter Selection for Open Ventilated (IC3A1) Wind Turbine Generator

IEC60034 is the standard for rotating electrical machines. IEC60034-5 defines ingress protection (IP) class of the machine and IEC60034-6 discuss mainly cooling methodology. A test has been performed on a wind turbine with squirrel cage induction generator of IP54 class. Cooling configuration was changed from IC6A1A6 (totally enclosed air to air cooled) configuration to IC3A1 (open ventilated). Paper presents some electrical and mechanical challenges associated with environmental conditions. Well protected duct and filter housing were used during testing. IC3A1 cooling bring certain advantages for the generator used in wind turbine application. This paper focuses on the need of proper filter housing selection to secure IC3A1 generator. Tradeoff between IP class, required performance, cost, serviceability of the machine are important factors and addressed in the paper. Recommendation has been made for a proper filtration selection to secure generator with good IP class. Recommendation is based on a test performed on a wind turbine.