Hydraulic Plant Life

The highly competitive environment in which hydro-electric utilities find themselves places increased emphasis on the need for reduction of both capital investments for equipment and parts replacement, as well as outage time for equipment repair and maintenance.

HPLIG is a collaborative technology focused program designed to assist hydroelectric utilities in their efforts to lower capital and operation costs, extend equipment life, improve efficiency, increase reliability and reduce outage times for equipment repair and maintenance, improve safety and environmental performance, improve risk based asset management decision making, performance evaluation and benchmarking techniques.

The Hydraulic Plant Life Interest Group is open to international utilities, independent power producers, government and other organizations that own or manage hydroelectric generating facilities. HPLIG Participants are free to choose the major projects in which they wish to participate. However, a condition of Participation is supporting the Technology Review Program designed to explore areas of importance to the majority of the group. The Technology Review Program costs are covered by a designated fee in addition to the annual participation dues.

HPLIG Strategic Direction:

• Hydropower Technology
• Capital and Maintenance Investment
• Maintenance Programming
• Workforce Productivity
• Environmental Performance

Current Projects

• Asset Management Task ForceTo initiate and maintain the CEATI Asset Management Users’ Group/Task Force which will provide a focused platform for best practices and technical exchange as well as identify, review, evaluate and pursue potential collaborative studies.
• Criteria for the Identification and Selection of Environmentally Acceptable (EA) LubricantsDetermine a list of test methods for aquatic toxicity and biodegradability and EA Lubricant acceptance criteria which can be consistently used across the hydropower industry.
• Alignment Guide UpdateTo solicit and consider input, update, and prepare for publication, an updated Alignment Guide, which:Includes experience gained by users of the current Guide as well as suggestions from users of the Guide for improvements and clarifications.
• Hydro Generator - General Maintenance and Inspection GuideThe objective of this project will be to develop a comprehensive set of hydro generator maintenance inspection guidelines for the stator and rotor windings, stator core and frame, rotor spider and rim, bearings and lubrication system, cooling system and excitation systems, , along with information and guidance on those repair activities that generally may be safely completed by plant maintenance personnel. To be as complete as possible, the guide will include tool and material lists as well as examples of repair techniques and references to published materials.
• Operation of Hydro Generators with Bypassed Stator CoilsThe objective of the project will be to produce a comprehensive overview and detailed technical guide for use by hydro plant managers in operating units with cut out coils in a safe and reliable manner.
• Penstock Task ForceCorrosion Guidance Penstock Inspection Scoping (including NDE guidance, steeply inclined to vertical penstocks) Instrumentation Guidance Repairs and Mitigation Guidelines Maintenance Procedures and Frequencies Seismic and Structural Upgrades Guidelines (including how to justify budget for these) Geotechnical Best Practices for Penstock Back-slopes and Foundations Guidance for Determining Remaining Life of Penstocks and Acceptable Operating Risk Development of a Model Penstock Safety Program Expansion Joints New or Alternative Materials (based on economic analyses and experience) Potential Failure Modes Guidelines for the various types of water conveyances
• Safe Protection of Hydro Unit Operating at Runaway SpeedThe objective of this study is to identify the critical areas of a hydro unit that can be adversely affected or damaged as a consequence of a unit reaching runaway speed; and further to provide a guide of precondition assessment, precautions and protections that can be implemented to assure the safety and integrity of a hydro machine after such an event.
• Hydraulic Unit Excessive Headgate Leakage Measurement, Prevention Methods and MaterialsIdentify a best in class for sealing agents in use in the industry. This should consider regulatory issues, availability, cost, storage and performance attributes; Identify the need for additional research for sealing agents; Identify methods/technologies to estimate or measure flow rates in a water passage; Provide a guide on how to establish when workers are at risk in the confined space because of the leakage flow rate; and Identify best practices for draining and monitoring water leakage in water passages for the purposes of inspection and maintenance.
• Hydro Unit Stator Core and Rotor Pole Replacement / Refurbishment CriteriaThe majority of stator core and pole iron damage on modern generators (post 1965) has occurred due to the failure of the stator winding. In addition, every utility is bent on maximizing plant output and increasing efficiency in preparation for the next 30 years of plant life or with regard to FERC leasing deadlines. Replacing components simply to increase reliability during a generator refurbishment should not be expected. The value in performing component condition assessment is usually with regards to efficiency improvements. The stator winding and the generator up-rate potential will not be included in this approach to the problem.
• Grounding and Bonding Best PracticesTo provide a comprehensive overview of best hydraulic plant grounding practices. This will include an outline of differences between among utilities in the USA and Canada. To provide an outline of the criteria used to design grounding systems. To provide a training tutorial that will enable plant managers to assess adequacy of their current knowledge of grounding protection. To provide an outline on how to undertake a condition assessment, test, and or design review of station grounding systems.
• Hydro Generator Start/Stops and Cycling CostsThe first two phases of this four phase project are as follows:
  
  Phase 1: Stator Insulation Aging Theory
  
  Review recent publications on insulation deterioration.
  Review key/similar Reclamation winding insulation ageing histories.
  Review the insulation ageing process documents of windings at Grand Coulee.
  Determine the ageing process of the G-19 winding that recently failed.
  Using a defendable logic based approach, identify and evaluate the factors that affect the loss of life of a generator start, stop, and cycling at Grand Coulee.
  Expand results to apply to hydro generators as a whole.
  Include recommendation on how to extend insulation life.
  Document results via a conference ready paper.
  Some of this information from phase 1 may allow us to draw reasonable conclusions as to condensing loss of life numbers so that an improved more accurate shut down/condensing time based calculation/decision can be made.
  
  Phase 2: Application of Results to Grand Coulee (BPA funded) and Hydro Units as a Whole
  
  Collect the necessary operating information from Grand Coulee.
  Apply economics to Grand Coulee specific generators to obtain dollar values per phase 1 findings related to unit stop/starts and cycling.
  Costs will depend on the number of different cases that would have to be considered for the various conditions and machines (third plant bar windings, and water cooled bar windings as well as for the multi turn windings and bar windings in the left and right plants).
  Extrapolate results to hydro generators as a whole.
  
• hydroAMP Program ManagementFour organizations developed a common process to streamline, simplify and improve the evaluation and documentation of the condition of hydropower equipment and facilities in order to support business decision-making. The effort resulted in the hydroAMP (hydro Asset Management Partnership)framework.
• Hydro Turbine/Generator Shaft Stress Analysis Methods and LimitationsThe objective of this project is to develop vertical unit up-rating design guidance for shafting in terms of the following:
  1. The maximum allowable stress or stresses for infinite shaft life based on shaft loading, shaft dimensions/features and shaft material and mechanical properties.
  2. Analytical procedures to determine remaining shaft life when stresses exceed the infinite life design guideance thresholds.
  The scope will include vertically oriented hydro turbine shafts of all sizes. Considerations for pump generation units will also be included. Forged as well as flat steel rolled and welded shafts will be included.
• Dissection, Condition Assessment and Analysis of Windings Taken From Failed In Service UnitsThis project proposes to collect the samples of the failed stator windings from the members of HPLIG and conduct detailed failure analyses. The analyses would consist of detailed visual inspection, dissection and bench testing required to determine, where practical, the root cause of the insulation failure.
• Brush Gear MaintenanceThe primary objective will be to provide a guide outlining the numerous design types of hydro brush gear systems, brushes and maintenance/testing techniques.

Recently Completed Projects