Analysis of Hoisting Electric Drive Systems in Braking Modes

Braking in hoisting drives is used to reduce the speed of the load (cargo) or to stop it completely. Braking can be realized using electrical and mechanical means; mechanical brake is used to hold the suspended cargo after disconnecting the driving motor from the supply. In modern hoisting electric drive systems, in addition to mechanical braking, electric braking is also used. Electric braking can be realized by transforming the driving electrical motor into the braking mode. The dynamic loads created in the mechanical parts of the hoisting drive depend on the magnitude of the braking torque, load torque, motor speed and other parameters. In this paper a mathematical analysis of the factors on which the braking process depend are analyzed. Recommendations about the appropriate braking methodology by which dynamic loads can be minimized are brought out. A mathematical model of the proposed hoisting electric drive is developed. © 2012 Jordan Journal of Mechanical and Industrial Engineering. All rights reserved