Synchronous Motors and Generators

High Efficiency, Power Factor Control

• Horizontal and Vertical
• 300 - 7500 hp, Up to 16,000 Volts

Because of its higher efficiency and special ability to provide a system power factor improvement, the synchronous motor is often the choice for large drivers. Its large air gap relative to that in an induction motor allows the use of larger stator slots. This is an important advantage for high voltage, high power applications. Additionally the designer has greater flexibility in combining starting torques and other characteristics to match widely varying system requirements.

Synchronous Rotor

• Starting Winding Versatility
• Brushless Excitation for Minimum Maintenance and Maximum Reliability

Synchronous rotors are designed primarily for applications requiring highly efficient motors. Each pole assembly is made from high strength steel laminations with a DC field winding encircling the pole body. The field winding consists of a rectangular section of insulated copper wire wound directly on an insulated pole body and bonded by a high temperature, high strength insulating epoxy resin which, when cured, results in a coil impervious to dirt, moisture and other contaminants. Synchronous motors are provided with an Amortisseur, or starting winding, consisting of copper alloy bars located in the pole face, parallel to the shaft, and brazed at the ends to copper alloy rings. The Amortisseur winding is tailored for the application to provide the required starting performance. Several types of synchronous rotor construction are used depending on the size and speed. All 4 pole motors have a laminated rotor of which the poles are an integral part.

Slower speed machines utilize individually removable laminated poles dovetailed or bolted to the spider. Motors with dovetailed poles generally have a laminated spider shrunk on and keyed to the shaft. A shaft mounted brushless excitation system is most generally used. Brushless excitation requires less maintenance with no brushes to change and is ideally suited for hazardous or contaminated environments.

The system includes:

• An easily controlled stationary exciter field,
• An exciter rotating element in which multiphase AC power is generated,
• A rotor-mounted rectifier system consisting of silicon diodes, thyristors and static switching devices.

A full line of slip ring synchronous motors is also available.

Vibration Equipment

Seismic-type such as RobertshawTM measures overall vibration. 1-6 units are located on the frame.
Proximity-type such as Bentley NevadaTM measures the shaft vibration. 2-5 units are located on the bearing housing.
Acceleration-type such as MetrixTM measures bearing housing vibration. 1-6 units are located on the bearing housing.

Other Accessories

Whenever required, the following accessories may be supplied:

• Surge protection
• Tachometers (capacitors and lightning arresters) •
• Overspeed switches
• Current transformers
• Slide rails
• Pressure switch
• Sole-plates
• Space Heater