· Disadvantages of Slip ring Induction Motor. Cost is high ( 3 times compare to squirrel cage) Large Size. Space requirement increases. There is wear and tear. There is sparking. Maintenance is large. Note: In Slip ring Induction Motor, Stator is wound for 3 phase winding.
Conventional AC operated crane drives use slip ring induction motor whose rotor windings are connected to power resistance in 4 to 5 steps by power contactors. ...
· A motor in a variable torque appliion will consume only 25% as much energy at 50% speed as it will at 100% speed. This is referred to as the Affinity Laws, which define the relationships between speed, flow, torque, and horsepower.
· WoundRotor (Slip Ring) Induction motor Used for constant speedservice requiring a heavier starting torque than is obtainable with squirrel cage type. Because of its lower starting current, this type is frequently used instead of the squirrelcage type in larger sizes. These motors are also used for varyingspeedservice.
SLIP RING / FREQUENTLY ASKED QUESTIONS HOW DOES A SLIP RING WORK? A slip ring passes electrical signals and power across a rotating interface using sliding electrical contacts. These contacts are typically a rotating ring and a stationary brush, or wiper, that slides along the ring surface during rotation. Materials and
· An induction motor is an AC electric motor in which the electric current in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding. The appliion of induction motor differs by the type of rotor which is being used:. Squirrel Cage Rotor; Slip Ring Rotor or Wound Rotor Type ...
Conventional AC operated crane drives use slip ring induction motor whose rotor windings are connected to power resistance in 4 to 5 steps by power contactors. ...
Changing Rotor Slip Important to match the motor to the load ensure that a change in motor power gives a desired change in load speed Load should have a substantial inertial components inertial torque can "carry" the load through brief periods when motor torque cannot Best used with motors designed for high slip
While used primarily for precision speed control, a VFD can also sometimes be used as a soft starter and is best suited for appliions where the acceleration characteristics must be highly consistent even with variable loads. However, VFDs have some downsides, being relatively expensive and requiring management of potential bearing currents.
· A Variable Frequency Drive (VFD) is a type of motor controller that drives an electric motor by varying the frequency and voltage supplied to the electric motor. Other names for a VFD are variable speed drive, adjustable speed drive, adjustable frequency drive, AC drive, microdrive, and inverter.. Frequency (or hertz) is directly related to the motor’s speed (RPMs).
In slip ring induction motor slip rings are provided with the rotor. We can add external resistance in the rotor circuit through slip rings. By the change in external resistance, the speed of the induction motor can be changed. Check out – Real Life Appliions of DC series motor. Cascade connection
of the motor will be higher, since these are proportional to the square of the current. Thus, both a high value for η and a PF close to unity are desired for efficient overall operation in a plant. Squirrel cage motors are normally more efficient than slipring motors, and higherspeed motors are normally more efficient than lowerspeed motors.
· Over my last 24 articles for Pumps Systems (see them here), I've offered advice solely on centrifugal month I'm shaking things up to address progressive cavity pumps (PC), which fit into the rotating positive displacement pump family.
· Using microcontrollerbased control systems, one can add speed variation to the system. In addition to the option of speed variation, the direction of rotation can also be changed, depending upon the motor control algorithms used. Permanent Split Capacitor (PSC) motors are the most popular type of singlephase induction motors.
· For motors controlled by a variable frequency drive (VFD), the control method used in large part determines a motor's efficiency and performance in an appliion.
AEGIS Shaft Grounding Rings protect motor bearings from the destructive shaft voltages produced by variable frequency drives (VFDs). This video compares the shaft voltage of a VFDrun pump motor before and after installation of an AEGIS ring. (To see this video in several other languages, see this Youtube playlist.)
6 Electrical Drives for Crane Appliion Nebojsa Mitrovic 1, Milutin Petronijevic 1, Vojkan Kostic 1 and Borislav Jeftenic 2 1University of Nis, Faculty of Electronic Engineering, 2University of Belgrade, Faculty of Electrical Engineering, Serbia 1. Introduction A crane is the type of machine mainly used for handling heavy loads in different industry