Generators in Utilities

With our comprehensive portfolio of reliable Siemens Energy generator service products, we can provide you with solutions that are tailor-made to your specific needs. By analyzing the individual operation and maintenance history of your turboset, our experts can customize concepts to help increase reliability, availability and flexibility. Those benefits are the key to success of improving your competitiveness and achieving maximum performance of your generator. We assist you with our unique services for generators, exciters and auxiliaries as well as with inspections and maintenance. Furthermore, with our digital service portfolio we can equip your plant with reliable on-line monitoring systems, predictive maintenance and digital data analysis for generators and high-voltage equipment. By choosing Siemens Energy generator services and solutions, you benefit from decades of experience and technical expertise.

Siemens Energy has the capability to service, repair and modernize air, hydrogen and water-cooled generators, including those of other OEM manufacturers. Depending on the application, our global Service network may be able to inspect OOEM (Other Original Equipment Manufacturer) generator components and recommend appropriate measures.
Furthermore, Siemens Energy can reverse engineer and manufacture OOEM parts, such as retaining rings, bearings and collector rings.

The operation of gas- as well as gas/water-cooled turbogenerators requires a number of auxiliary systems that supply the unit with operating fluids such as gases, seal oil and water. Those generators typically require explosion-protected auxiliary systems.
Siemens Energy offers a comprehensive package of explosion-protected auxiliary systems and can provide a spectrum of innovative service solutions from plant specific planning through installation and commissioning.

With over 150 years of experience, Siemens Energy is a world leader in generator technology and has manufactured many of the largest and most efficient generators in the world.

With Siemens Energy as your service partner, you can have the full benefits of the expertise of our turbine-generator factory personnel, design engineering, service engineering groups, and our regional management and service expertise. We are knowledgeable of potential turbine-generator issues through significant fleet experience and have developed an enormous backlog of field processes, procedures, tooling and trained personnel to quickly address them.

In the current state of the energy market utility operators are in need of generators with resilience to meet the demands of generator operational flexibility.

Siemens Energy generators have demonstrated a long service life, however the life of the generator is subject to normal aging processes which can manifest differently depending on the generator model and operational mode.

In today’s operating grid demands, normal aging processes can be exacerbated and accelerated by changes in operating modes, with many startup and shutdowns, frequent turning gear operation in standby mode and fast load changes in the part load range, which can apply greater stress to the individual generator components.

Generator Replacement

Complete replacement is in some cases the more cost-effective alternative. A detailed cost/benefit analysis can help you decide if and when an investment in a new generator is economically beneficial compared to maintenance and service expenditures for the current generator. Siemens Energy can provide a matching generator for almost all generator types and configurations.

Specifically designed to replace smaller hydrogen- or water-cooled generator, the air-cooled Footprint™ generator is an easy to implement solution in which the existing foundations and interfaces can be used wherever possible.

Detailed information about our Footprint™ concept

Generator Uprates

When the power output of the turbine is increased, the generator capability needs to be adapted accordingly. Using specifically developed analysis measures, our Siemens Energy experts can quickly assess various options for uprating your generator and provide an individual proposal.

Siemens Energy can offer the following measures for uprating your generator:

Rotor, stator and exciter upgrades with enhanced design for increased rating
Reducing cold gas temperature in generators with closed air-cooled systems
Increase of hydrogen pressure for gas-cooled generators
Uprate of air-cooled generators

Implementation of a Synchronous Condenser Solution

The continuously growing renewables share as well as volatile grids can have a significant impact on the synchronous condenser power production equipment and also on the transmission system operation. The consequences can be multifaceted. Remaining fossil units may be highly cycled and the energy flow in the transmission system complex. At the same time, the stability of a converter dominated transmission system is challenging. The frequency and voltage control as well as fault ride through capability can require installation of new additional equipment for stable and safe grid operation.

A synchronous condenser is a turbo generator without turbines, connected to the grid via unit transformer, that can be implemented by one of the following options:

Conversion of existing generators to a synchronous condenser
New generators for synchronous condenser applications

In power plants with several turbine generator sets, the implementation of an additional generator in synchronous condenser operation may represent the most cost-effective solution for increasing the plant output. The power factor in the existing generators is adjusted to produce more or even exclusive active power (MW). The missing reactive power fraction (MVAr) is to be compensated by the synchronous generator which is operated as a motor at zero load. The effort associated with the installation of an additional generator in the power plant architecture can be compensated for by the following advantages:

Eliminates need for extensive technical changes to the existing generator
Higher flexibility with regard to the provision of reactive power
Use of an additional generator in power plants with several generators of the same type as a “productive reserve”, e.g. in the event of damage to a generator

Find further information about our portfolio of generators for synchronous condenser applications:

Generators portfolio

With any modernization it is important to verify that all of the measures in the power plant are coordinated. Siemens Energy provides project management and can coordinate and harmonize the various scopes of supply and services. Additionally to generator modernizations, Siemens Energy is the right partner to provide comprehensive plant service solutions for high-voltage equipment, transformers, isolated phase bus ducts as well as excitation equipment (AVR).

Your overall benefits can include:

A turbine generator, as the key electrical component of the plant, can face new operational stresses created by more flexible grid behavior
Service and maintenance measures should also be adapted to the new requirements in order to ideally position the generators for the future demands
A condition-based maintenance, refurbishment and replacement strategy can reduce the potential for sudden outages for older generators

Use online condition monitoring and diagnosis systems to receive information about the state of the machine during operation
Condition based maintenance with extended operating periods in between stand stills can be achieved
Interaction of partial discharge, stator end winding vibrations and air gap magnetic flux monitoring in correlation with the operational parameters enables a powerful generator diagnostic

Modernization & Upgrades for Turbogenerators

Our comprehensive generator and exciter services and solutions power your success!

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Rotor Modernizations

Stator Modernizations

OOEM Solutions

Exciter Modernizations

Auxiliary Modernizations

Online Monitoring & Diagnostics

Generator Services

Generator Modernizations

Comprehensive generator modernization solutions can be offered by Siemens Energy and are described in the following:

Generator Replacement

Generator Uprates

Implementation of a Synchronous Condenser Solution

Leverage the Profitability of your Plant

Reliability Increase

Availability Increase

Power Increase

Condition-based Maintenance

Efficiency Increase

Increased Lifetime

Generator Online Monitoring - installations worldwide

Technical Papers

Fast GVPI Stator Rewind Experience

Impact of New Flexible LoadOperation and Grid Codes on Turbine Generators with a Focus on End Windings

OnlineMonitoring - Early Detection and Diagnosis of Initiating Damages in Turbo Generators