systems for wound rotor motors and frequency converter drives. Improvements in power electronics technology and controls have resulted in variable frequency converters that offer high efficiency, high reliability and availability at competitive cost. The first Gearless …

I have working with a 4.16kV wound rotor motor with the rotor connected through slip rings to a rheostat during starting. Obviously after the motor has started the leads coming from the rotor are shorted together in the rheostat. My question is after the rotor leads are shorted together is there still voltage and current on these leads.

1930 Wound Rotor Motor Mill Drives. Wound rotor motor - Wikipedia. The induction motor drive has many applications like it is used in fans, blowers, mill run-out tables, cranes conveyers, traction, etc. The induction motor drive is self-starting, or we can say when the supply is given to the motor, it starts rotating without any external supply

Wound Rotor Motor Mill Drives. A wrim is a type of induction motor with unique construction, in the cement and mining industry for starting and driving large grinding mills in fact, until about 1985, a wound rotor induction motor was the, motors on grinding mills, slip power recovery drives have been applied in other industries, such as in municipal chat online.

I have seen many wound rotor motors with the slip rings shorted and run on a VFD. Make sure the VFD carrier frequency is set to its lowest value, usually 2k or 2.5k. You best method of shorting the rotor AKA slip rings, is in the motor junction box. You also DO NOT need to over size the drive. If you have a 20 hp motor, use a 20 hp drive.

is currently the gearless mill drive (GMD). In GMD systems the motor's poles are directly installed on a pole flange on the mill shell, and the body of the mill itself becomes the rotor. Ring-geared mill drive For mills with standard diameters or requiring less than 20 MW (approx.) of power, ring-geared mill drives (RMDs) offer the best solution.

Transcribed image text: Roughing mill set-up A 1500 hp wound rotor motor drives a roughing mill setup to reduce a hot metal steel billet from 200mm x 200mm to 120mm x 120mm. Due to its continuous operation and in consideration of the heat, the gearbox, which the motor drives need constant circulating lubrication via an oil pump driven by a 7.5 hp motor.

DIRECT CONNECTED Ball Mill DRIVE. When power exceeds 300 HP a direct connected drive is recommended. This drive is also applicable for lower power requirements if desired. Synchronous motors are preferred, but in some cases wound rotor motors may be used. Motor speeds will vary from 225 rpm to 450 rpm.

Synchronous motors have 98.5% efficiency in converting motor output to power at the mill shell due to the pin-ion and gear. Wound rotor motors with gearbox reducers have a 98.5% gearbox efficiency and 98.5% pinion effi-ciency resulting in an overall 97% efficiency converting motor output to power at the mill shell. Losses are multiplied to ...

rotor windings and the external rotor resistors [6]. SER is an alternative approach to induction motor speed control. Modern SER drives consist of back-to-back voltage source converters which are positioned in the rotor circuit of a wound rotor induction motor (Figure 2). These converters decouple the mechanical and electrical rotor

Jim McKee (deceased) Alabama Electric Motor Service Sheffield, Alabama Technical Education Committee Member The slip ring or wound rotor induction motor (WRIM) has been used in a variety of applications. Many of these applications use the WRIM's high starting torque capabil­ity while limiting current to start and run very high inertia loads such as hammer mills, rolling mills, centri­fuges ...

MCW were asked to produce a control system for 75kW slip ring fed, wound rotor induction motor that was being used to drive a steel rolling mill via a Radicon gearbox. At the heart of the system MCW used the Fairford Synergy intelligent soft starter to provide a controlled soft start and soft stop for the motor.

Transcribed image text: A 1500 hp wound rotor motor drives a roughing mill setup to reduce a hot metal steel billet from 200mm x 200mm to 120mm x 120mm. Due to its continuous operation and in consideration of the heat, the gearbox, which the motor drives need constant circulating lubrication via an oil pump driven by a 7.5 hp motor.

Wound Rotor Induction Motor - Slip Power Recovery. Large wound rotor induction motors (WRIM) have been used in some industries for decades. In the cement and mining industries, high horsepower WRIMs are used on large grinding mills, where they have the advantage of controlled starting characteristics and adjustable speed capability.

A major alternative to the Kramer system for wound-rotor induction machine drives was the Scherbius system, introduced in Germany in 1907.Historical evidence indicates that pioneering Scherbius rolling mill drives were installed at the Saucon works of the Bethlehem Steel …

Figure 4: typical SAG mill motor drive equipment. Since such drives Figure 3: one of two wound rotor motors for a 10,000kW SAG mill ICR SEPTEMBER 2009. are in volume production at this time, support should be available for years to come. Getting renewal parts for …

Mar 7, 2014. #1. I am new to this site, looking for some help with one of our old Westinghouse Motor Starters. We have an 1200 HP Synchronous motor with brushes. We have been experiencing exciter problems quite often when we have to restart or after a disturbance within our mill. The current problem we are experiencing is the mill was offline ...