450V 300KW generator rotor varnish treatment

Rewinding a low voltage generator 225 KVA, 14 pol., 400 V

Spraying metal powder. Edit Required Shaft dimension

Neuwicklung Generator, 800 KVA, 5,2 KV, 750 rpm / min

Slip ring Loseless synchronous generator

Construction of a power plant with synchronous generator

Generators Bearing and Alignments

Bearing and Alignments 
 Defective bearing and shaft seats that are sprayed metallic with Castolin method to the selection of the correct bearing and installation conditions.

 

Generators Brushless Conversions from carbon brushes to co-rotating diodes

Generators of older design are fitted to the then state of the art with brush-type exciter machines.
This is a more or vinous large perturbation term for your business that gives rise to repairs. Particularly unpleasant is the pollution of the machine by means of electrically conductive brush abrasion. In connection with the occurring cracks in the course of time insulation This represents an increased risk of damage winding.

To increase the permanent availability, we offer a conversion to co-rotating diodes (with removal of all carbon brushes) on.
In the future, thus also sets a lower maintenance, which reduces in principle to the bearing lubrication. Brush control- and exchange and cleaning measures for brush wear omitted.
Our mechanical workshop and testing we are able to carry out everything in our own factory and modernize your generator.
In older machines often confronted with the problem that only has the collector of the exciter machine due to wear and various edits insufficient fin height, so no further over speeding longer possible.
As an alternative to renewal of the collector therefore urges the conversion to a brushless excitation, combined with all the benefits of continued use, almost.Generators of older design are fitted to the then state of the art with brush-type exciter machines.
This is a more or vinous large perturbation term for your business that gives rise to repairs. Particularly unpleasant is the pollution of the machine by means of electrically conductive brush abrasion. In connection with the occurring cracks in the course of time insulation This represents an increased risk of damage winding.
  

Pole pieces on the disc rotor: no tonal continuous geometry appropriate - © Enercon

Stator production © Enercon

Stator production: A special processing procedure ensures enables each
A continuous phase winding without interruption. - © Enercon

How to make a Frame 5 generator ‘new’ in 15 easy steps

Posted on November 19, 2012 by Team CCJ

Your Frame 5 generator may be a classic—between 20 and 40 years old—perhaps even an antique (over 40). Physical age doesn’t matter much in most cases because these machines were designed conservatively, constructed with craftsmanship, and built to last. How long it pays to keep Frame 5s older than about 25 years in service continues to be a question on the minds of asset owners. Many had been content with just letting these workhorses run down to retirement. But that was before their value increased as ancillary-services providers for regional grids challenged to maintain system stability in the new era of must-take renewables.
Maintaining your unit in top condition begins with proper operation. During turbine overhauls, conduct routine electrical, mechanical, and NDE assessments and perform all associated generator maintenance. Take advantage of today’s upgrades when the economic equation points in that direction; extend your vintage Frame 5 generator’s life and possibly increase its capacity. With such enhancements, your classic will gain value and stand the test of time.
Here, engineers from TurboCare, which overhauls many Frame 5 generators each year at its shops worldwide, walk you through the key steps involved in rehabilitating a vintage machine to virtually as-new condition.

	1. Classic Frame 5 generators typically arrive at the shop in poor condition. Mechanical, electrical, thermal, and environmental aging influences have taken their toll. Stator and rotor winding insulation systems usually are obsolete. Plus, retaining rings, collector rings, core iron, and the end-basket support system are dated and should be upgraded.
	2. A classic commonly contains asphalt-mica stator windings. The straight-section outer binder, strand insulation, and/or end connection putty may contain asbestos; test prior to demolition. If positive, use only trained abatement specialists.  As the stator windings are extracted, critical dimensions are taken for the engineering and redesign process.
	3. Once stripped of the original windings, the stator housing and core iron are grit-blasted clean. Great care is required during this operation, because the stator laminations are susceptible to “smear” damage. Perform a near-flux core loop test to requalify the iron for reuse.
	4. A full core replacement can be performed with either stamped punchings or laser-cut laminations. The lamination steel used should be either grade M6, Cold-Rolled Grain-Oriented (CRGO), or M15, Cold-Rolled Non-Grain-Oriented (CRNGO), with C5 core plating as the interlaminar insulation.
	5. The original two-turn full diamond coils are upgraded to two-turn, 360-deg Roebel half-coils, which are far superior to the original windings in many ways, including these: They have more copper (lower I2R losses), more conductors in-hand (lower eddy-current losses), and a Roebel transposition (lower circulating-current losses), as well as a  modern resin-rich mica thermosetting insulation system.
	6. The new and improved windings are installed into the stator core iron together with the following upgrades: End-basket support system, vertical slot fillers, side packing, stator slot wedge system, encapsulated end connections, circuit ring bus, new RTDs, new heaters, a flux probe, and partial-discharge monitoring system.
	7. A comprehensive acceptance program is conducted following a stator-winding upgrade and includes successful completion of an El CID core test, wedge-tightness mapping, insulation resistance, Polarization Index; controlled over-voltage; ac and dc high potential, power factor and tip-up, and phase resistance.
	8. The rotor is dismantled down to a bare forging, taking steps to avoid the release of asbestos-bearing materials, if present. Copper samples are removed from the main field winding and lab-tested for composition, tensile strength, hardness, and yield strength. Main field windings generally are suitable for reuse.
	9. Rotor components—such as the rotor body forging, retaining rings, blower hubs, and rotor body wedges—are cleaned down to grey metal. Each individual part is subjected to requalifying nondestructive testing, which may include dye-penetrant, ultrasonic, eddy-current, and magnetic- particle examinations. Non-conforming parts are either repaired or replaced.
	10. The reconditioned and requalified main field coils are wound back into the rotor-body forging. The latest turn-to-turn and ground-wall insulation systems are incorporated into the process. Slip-planes, critical to unimpeded axial thermal expansion and contraction of the windings, are designed into the upgraded main field winding system.
	11. Specially designed and fabricated slot and end-winding compression fixtures are installed on the newly installed coils, forming a symmetrically round and dimensionally concentric main field winding. The rotor is then induction-cured, to set and stabilize the associated adhesives while seasoning the windings.
	12. All new top creepage blocking is installed along with the rotor body wedges and a new permanent end blocking system. Should resin-load materials be used, the end windings are compressed once again, and the rotor windings are subjected to a second and final induction curing process.
	13. The rewound, reassembled, and fully upgraded rotor is placed in the high-speed balance facility. There it is balanced to operational speed, subjected to a minimum 10% over-speed run, and at-speed electrical testing—including insulation resistance, ac impedance, RSO and/or flux probe.
	14. The generator rotor now is completely upgraded, uprated, and “zero houred.” With all new turn-to-turn, ground wall, and retaining-ring insulation systems, modern 18Cr18Mn retaining rings, and new collector rings, the classic Frame 5 rotor is better than when it was new and ready to begin its second life cycle.
	15. The Frame 5 generator is a true classic in every sense of the word: simple in design, rugged in construction, and easily acceptant of modern upgrades and uprates. Rebuilding of vintage machines typically makes better economic and business sense than buying new. Owners can expect years of relatively maintenance-free service. source:http://www.ccj-online.com/how-to-make-a-frame-5-generator-new-in-15-easy-steps/

Wind Turbine Generator Stator Stamping Lamination

Electric generator stator winding of the three-phase AC induction

Reinsulation of 18.8 MW Generator

 coil-strip

completed coil-fitted to rotor

completed-coil

 pole coil heated and pressed

SR4 GENERATOR MAINTENANCE 1000 KW.

achievement cap be removed with the extractor, we discover that the bearing was not installed right, is an open ball box for lubrication . this generator, modern as it is, comes with sealed bearings lubricated for life, and no lubrication  enabled. the overheated bearing was installed, with wear and about to fail .
Technical recommendation: when a generator is Travado bearing at the top and the same extractors remove it fail, never resort to the method of the hammer, this could only twist the shaft or crack the lid. appropriate solution is the force controlled hydraulic puller.

Generator Maintenance

This generator had sulphation (by proximity to the sea), also baristores block burst. Was undertaken generator maintenance, triple layer was applied coating, joint replacement and bearing rectification.

The generator is practice a recalibration of valves and injection system tuning. Note, that the adjustment of valves for admission was 0.015, and 0.030 for escape. The injection timing of this engine should be 86.80 mm, and was 87.20mm. this advancement in injection time, caused unwanted sounds in the engine, so as to absorb the load problems. With the proper injection time adjustment, the engine sounds good, and its performance is much better than before.

Synchronous and Asynchronous Generators

CONTENTS :
1. SYNCHRONOUS GENERATOR ( multipole ) .
2 . ASYNCHRONOUS GENERATOR .
INTRODUCTION .
The generator converts the mechanical energy produced by the rotor into electrical energy. Asynchronous generators are often used squirrel cage with capacitor banks to improve power factor, but also can be used for asynchronous and synchronous generators winding rotor . The network connection may be direct or indirect , depending on whether the turbine operates at constant or variable speed . Working indirectly connected network leverage peaks get wind speed, but the generator produces power at variable frequency needed fitness equipment to dump energy in the network. In the direct connection , the network itself limited the rotational speed of the generator , so that no peaks greater advantage wind energy.
1. SYNCHRONOUS GENERATOR ( multipole ) .
The synchronous motor is unconventional and can be used in large industries for power factor correction in this case , the speeds of the rotor and stator tend to equalize , thus the name Synchronous .
Figure 1: Synchronous Generator .
Advantages and disadvantages :
- Optimized control .
- Does not use multiplier .
- Low slip .
- Reduction of stress.
Two . ASYNCHRONOUS GENERATOR .
An induction motor is a conventional engine and the term asynchronous is used , because the rotor speed theoretically can never reach the speed of the stator ( Offset) .
Figure 2: Asynchronous Generator .
The squirrel cage motor comprising a rotor constituted by a plurality of metallic conductors (typically aluminum ) arranged parallel to each other , and short-circuited at its ends by metal rings , that is what forms the squirrel cage call for its visual similarity with a squirrel cage . This ' cage ' is filled with material, usually stacked plate . Thus, a system is achieved n -phase conductors (n being the number of drivers ) located inside the rotating magnetic field created by the stator , which has a physical system is extremely effective , simple, and very robust ( basically no maintenance required ) .
The wound rotor motor having a rotor constituted , instead of by a cage, of a series of conductors wound about it in a series of slots on its surface. In this way, a winding inside the stator magnetic field , the same number of poles ( must be built with great care ) , and moving. This rotor is much more complicated to manufacture and maintain than the squirrel cage , but allows access to it from the outside through rings that are the windings shorted . This has advantages such as the possibility of using a motor starter that can adjust the speed and torque , as well as reduce the starting current .
In either case , the rotating magnetic field produced by the stator field coils generate induced currents in the rotor , which are used to produce this movement .
1) Asynchronous ( squirrel cage ) .
Figure 3: Asynchronous Generator squirrel cage .
Advantages and disadvantages :
- Easier to manufacture.
- Less versatility.
- Need soft synchronization network ( thyristors ) .
- It controls the power factor capacitor stages needed .
2 ) Asynchronous with wound rotor .
Figure 4: Asynchronous Generator rotor winding.
Advantages and disadvantages :
- Allows inject and extract energy from the rotor.
- Injecting different frequencies to generate power rotor is achieved at very different speeds of synchronism .
- Variable speed generator ( of 900-1500 rpm).
- By allowing the extraction of energy from the rotor, is able to generate up to 10% of the energy produced .
- Requires synchronization before generating network .