A Solid State, Variable-Frequency, 3-Phase Power Source With Individual Harmonic Control

The paper describes a novel 3-phase transistor power inverter distinguished by its capability for obtaining from a constant voltage d. c. supply, 3-phase variable-frequency, variable-voltage power containing controlled amounts of 5th, 7th and 11th harmonics. The phase relations between fundamental and harmonic components are identical in each of the three phases; amplitudes can be controlled independently.