H ELECTRICITY
H02 GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
H02P CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
9/00 Arrangements for controlling electric generators for the purpose of obtaining a desired output
H02P9/007 Control circuits for doubly fed generators