Induction machine drive in energy efficient industrial forklift

This paper investigates the effect of an induction machine (IM) drive on the efficiency of an electric energy recovery system of a hydraulic forklift. The control of the hydraulic system is implemented directly with a motor drive without control valves. The paper provides accurate evaluation of the hydraulic system and a detailed analysis of electric part of the working machine. A theoretical analysis is made and the model is verified by practical results. Finally, possible improvements of the efficiency in the suggested system are considered.