kevin marshall, pe gc pud hydro engineering manager nwha conference february 18, 2014 grant county...

Kevin Marshall, PEGC PUD Hydro Engineering Manager

NWHA Conference

February 18, 2014

Grant County PUDPlant Upgrades at Wanapum and Priest Rapids

Dams

Ongoing Upgrades for Wanapum Dam

Turbine Replacement (Note: GCPUD took advantage of CREB bonds and a DOE design/development grant) Work is complete.

Generator replacements New exciters Digital Governors Transformers

Reasons for Turbine Upgrades

Original turbine runners had reached the end of their useful life Blade crack repairs Trunnion seal issues Operating linkage failures Cavitation repair costs -

$75,000/unit/year (1987-1993 average costs)

Performance improvements

Improved fish passage survival

Wanapum Turbine Upgrades Design Features

Semi to fully spherical Larger diameter: 20 inch increase Deeper setting : 3.315 feet deeper

Performance Improvements Increased capacity: 120khp to 150khp Efficiency improvement: 3% average weighted

efficiency Cavitation repair costs: $0

Reasons for Generator Upgrades

Replace components at the end of their life.

Capture increased output of new turbines

Wanapum Generator Upgrades

New Parts Complete Rotor Complete Stator Generator Shaft Ventilation System Excitation System Air-Gap Monitoring

Rotor spider arrives in 3 sections, stator frame in 4

Wanapum Governor/Unit Control Upgrades

What Mechanical governors

replaced with digital Dynamic exciters

replaced with static exciter and digital controllers

Why Spare parts no longer

available Serviceman knowledge not

transferred with retirements

Improved control/efficiency Improved protection More info/better trouble

shooting Lower costs to maintain

Existing Wanapum Mechanical Governors

New Wanapum Digital Governors

10th turbine, 4th generator, 4th exciter, and 3rd governor complete and put into service October 2013

5th generator, 5th exciter, and 4th governor under construction

10th generator and exciter to be completed in 2019 New turbines have a averaged, weighted efficiency

gain of 3% As tested new generators have an increased efficiency

from 98.0% to 98.5% 2 of 5 transformers replaced, 3rd transformer in process

Current Wanapum Status

Priest Rapids Dam Upgrades

Planned Upgrades for Priest Rapids Dam

Turbine Replacement or life extension

Generator rewinds New exciters Digital Governors Transformers

already replaced

Efficiency improvement Life Extension Aging equipment

First unit in service in 1959 Generators

Rotor pole problems including pole to pole connection failures (as pictured)

Stator Winding age (oldest unit = currently 27 years old)

Exciters are obsolete Turbines starting to exhibit problems

Increased cycling of governor oil pumps

Wicket gate operating ring wear

Reason for Upgrades

Goals Utilize lessons learned from Wanapum project Obtain as many qualified bids as possible Competitive turbine hydraulic model testing Integrate biological considerations into design

effort

Turbine Upgrade Process

Turbine Upgrade Process

Step 1: Hydraulic design contract Professional Services Agreement Prequalification process – three

contractors prequalified All design solutions finalized by

contractors ahead of bidding All design solutions verified by

independent hydraulic laboratory Step 2: Manufacture and supply

contract Bidders must participate in

hydraulic design contract to bid Performance guarantees verified

prior to bidding

Turbines Model testing was completed last week in Lausanne,

Switzerland for the 3 qualified vendors Bids are due March 5th Contract award this summer (if economics are

favorable) Generators: Pre-qualification of Vendors in process Controls: Governor specifications are in process Field work for upgrades is scheduled for 8/1/2016

Status of Priest Rapids Upgrades

QUESTIONS

Priest Rapids and Wanapum Upgrades