Space Vector Modulation Algorithm for Large Electric Drives

In this paper a new Space Vector Pulse Width Modulation (SVPWM) algorithm is proposed for multilevel voltage source inverters. The proposed algorithm directly identifies the two level subhexagon in which the reference voltage vector lies. The switching sequence corresponding to a two level inverter is determined. The proposed method can be extended to any m-level inverter and a generalized algorithm is proposed. Based on the mathematical model presented, a "five level inverter-induction motor" system is investigated in steady state and transient responses. The induction motor is controlled using Field Oriented Control (F.O.C.). The improvement of the control scheme is achieved using Mamdani's fuzzy logic controller for both rotor speed and inverter current. The electric drive system is simulated in case of a five level inverter and the results presented verify the good performance of the proposed SVPWM algorithm.