Control of Double Output Induction Machine Based Stand Alone Variable Speed Constant Frequency Generator with Nonlinear and Unbalanced Loads

The control algorithms proposed in the literature so far for the Double Output Induction Machine Based Variable Speed Constant Frequency (VSCF) stand alone generators suffer from the disadvantage of loss of 'field orientation' during sudden load disturbance at the machine terminal. As a result, undesirable transients are observed in the load voltage during such transients. This paper presents a new control strategy for such generators where the primary objective of the control scheme is to maintain constant voltage and frequency at the output of the generator irrespective of the prime mover speed and load variation. The proposed control algorithm is suitable for all types of loads such as balanced, unbalanced, linear and nonlinear. Simulation results are presented to validate the effectiveness of the proposed scheme.