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 realizedusing electrical and mechanical means; mechanical brake is used to hold the suspended cargo after disconnecting the drivingmotor from the supply. In modern hoisting electric drive systems, in addition to mechanical braking, electric braking is alsoused. Electric braking can be realized by transforming the driving electrical motor into the braking mode. The dynamicloads created in the mechanical parts of the hoisting drive depend on the magnitude of the braking torque, load torque, motorspeed and other parameters. In this paper a mathematical analysis of the factors on which the braking process depend areanalyzed. Recommendations about the appropriate braking methodology by which dynamic loads can be minimized arebrought out. A mathematical model of the proposed hoisting electric drive is developed