Design and simulation of H-bridge fed direct torque controlled electric traction drive

This paper presents the performance of electric traction motor drive consisting of an AC-DC converter fed vector controlled induction motor drive. The variable frequency induction motor drives used in AC traction system consist of uncontrolled ac-dc converters and voltage source inverters feeding the induction motor. Such converters induce power quality issues in the distribution system such as injecting harmonics which leads to voltage fluctuation, reactive power and low power factor issues. The converter topology discussed in this paper provides the constant dc link, keeps the input power factor close to unity and also reduces the THD of AC mains current. Direct torque control method is used to control H-bridge fed traction motor drive. Modelling and simulated results are presented to demonstrate the features of electric traction drive. The necessary modelling and simulations are done in MATLAB Simulink.