mechancial motor braking

My name is Ryan.Im am looking for information on various mechancial braking methods on three phase and single phase induction motors.I have some information on electrical methods of braking,ie. d.c injection,plugging but if possible i would like information on capacitive braking.

 

[jackass]

There are many ways to brake a motor ,such as you have outlined above but i have heard about flux braking ,this relies on increasing the motor losees in a controlled way; invererts with direct torque control have this capabiliity whenbraking is needed, the freq is reduced and the flux in the motor is increased which in turn increases the motor capability to brake.

 

[EKTORAS]

rioneill,

Capacitive braking that you are asking for, belongs to another category of braking named regenerative braking. In this kind of braking kinetic energy is removed from the rotating load and the motor is instantly turned into a generator. We can do this, for example, with a motor that has two distinctive speeds of rotation, changing the speed from the higher (low number of poles) to the lower one (higer number of poles). The point is that when the rotor speed falls to this lower speed, generation effect stops and as a result braking stops. Here enters the idea of capacitor, by which, having removed the mains connection, we can self excite the motor to an even lower "synchronous speed" thus prolonging the generation period and extending the braking action even further.