Spiral vector theory of AC motor analysis and control

The spiral vector theory is proposed. In AC circuit theories it unifies steady-state AC theory and transient-state theory by providing common variable expressions. In analyses of three phase machines the spiral vector method makes it possible to write performance equations in terms of variables of one phase (the phase segregation method). Based on the analytical results obtained FAM control of induction motor torque is proposed. Superior control features are derived for the induction motor, making torque-speed curves completely straight, and torque response instantaneous. Transfer functions are derived for induction motor torque control. Transient phenomena of controlled synchronous motors were analyzed by means of the spiral vector method.<>