Geoff Klempner - Handbook of Large Hydro Generators

2 Chapter 2 Figure 2.1-1 Cross section of core showing inter‐laminar damage and the eddy... Figure 2.1-2 Inter‐laminar insulation reduces eddy current losses in the ste... Figure 2.1-3 Laminated‐core eddy‐current loss as percentage of full‐block lo... Figure 2.1-4 Stator core segment described. Figure 2.1-5 Showing the U shaped or “hairpin” coil. Figure 2.1-6 Lamination stacking in the stator, also showing the conventiona... Figure 2.1-7 Heavy lamination segment with I‐shaped blocks (radial duct) – r... Figure 2.1-8 Shows double dovetail design that prevents core buckling. Figure 2.1-9 Core‐to‐keybar mounting arrangement in the stator frame. Shim l... Figure 2.1-10 Shows another arrangement for the core bolt. Figure 2.1-11 For demonstration purposes this figure shows an insulating bus... Figure 2.1-12 Showing the vent lamination with the hole to accommodate the b... Figure 2.1-13 Shows compression washer assembly. Figure 2.1-14 Shows keybar and core clamping bolt as one piece with threaded... Figure 2.1-15 76 MVA newly piled stator core showing the clamping finger ass... Figure 2.1-16 86 MVA newly piled stator core showing the first packet with s... Figure 2.1-17 Shows finger plate installation with adjustable fulcrum points... Figure 2.2-1 Shows outside part of stator frame showing the wrapper plate an... Figure 2.2-2 Typical soleplate positioned in the foundation awaiting final s... Figure 2.2-3 Shows another style of soleplate with double “J or T” hooks. Figure 2.3-1 Four pole generator flux pattern. Figure 2.3-2 Flux distribution and flux density at no load obtained by FE si... Figure 2.3-3 Flux distribution and flux density at rated load obtained by FE... Figure 2.3-4 Flux distribution and flux density during sudden short circuit ... Figure 2.3-5 Shows the flux distribution in the over‐excited mode with field... Figure 2.3-6 Shows the flux density in the over‐excited mode with field curr... Figure 2.3-7 Shows the flux distribution in the under excited mode with fiel... Figure 2.3-8 Shows the flux density in the under excited mode with field cur... Figure 2.7-1 Typical multi‐turn coil strand configurations. Figure 2.7-2 Typical single turn Roebel bar configuration. Figure 2.7-3 Cross section of stator bar in the stator slot. Figure 2.7-4 Cross section of a stator multi‐turn coil in the stator slot. Figure 2.7-5 Shows a two turn bar in the stator slot (teeth are adjacent to ... Figure 2.7-6 Stator endwinding showing reversing group jumper connection on ... Figure 2.7-7 Stator endwinding showing reversing group jumper connections on... Figure 2.7-8 Showing reduced eddy current losses with individual strands of ... Figure 2.7-9 Individual strand cross section to reduce losses from right to ... Figure 2.7-10 Looping of a coil with inverted turn. Figure 2.7-11 Roebel transposition 3D view. Figure 2.7-12 Roebel bar principle. Figure 2.7-13 Temperature profile of a double‐stack stator bar with separate... Figure 2.7-14 Cross Roebel transposition‐temperature profile of a double‐sta... Figure 2.7-15 Cross Roebel transposition – temperature profile of a double s... Figure 2.7-16 Shows a 3D representation of a typical water cooled stator bar... Figure 2.7-17 Direct cooled stator winding (rotor poles removed). Figure 2.7-18 Shows the black semiconducting material and the grey Silicon C... Figure 2.7-19 Flat side‐packing (top) and ripple spring (bottom) with semico... Figure 2.7-20 Shows stand up view of Figure 2.7-19 to illustrate the ripple ... Figure 2.8-1 Typical packing material and wedge assemblies. Figure 2.8-2 Various types of wedge assemblies. Figure 2.8-3 Shows core packet and fretting at the interface of wedge groove... Figure 2.8-4 Shows minimal damage to wedge groove after cleaning. Figure 2.9-1 Stator endwinding support system for a bar winding. Figure 2.9-2 Stator endwinding support system for a multi‐turn coil. Figure 2.10-1 Two parallel Y connected winding. Figure 2.10-2 Four parallel Y connected winding. Figure 2.10-3 Two parallel paths with long series jumpers. Figure 2.11-1 Generator main leads – new installation with tags to show test... Figure 2.11-2 Shows split phase CT's on main output leads. Figure 2.11-3 Generator neutral leads – new CT's tested and ready. Figure 2.12-1 Shows a modern day rotor. Figure 2.12-2 Shows rotor from 1925 without the field poles installed. Figure 2.12-3 The beginning of rim piling. Figure 2.12-4 Shows rim stack at an early stage of progression. Figure 2.12-5 Rim being piled showing the stacks of steel laminations and ri... Figure 2.12-6 Rim press operation during the piling process. Figure 2.12-7 Shows rotor rim donuts. Figure 2.12-8 Fully piled rim with no end plate – just steel segments on top... Figure 2.12-9 Shows another rim design with end plates. Figure 2.12-10 Rim key in final position. Figure 2.12-11 Tapered rim keys set in final position by hydraulic jack. Figure 2.12-12 Torque key installation in progress. Figure 2.13-1 Shows a cast and fabricated spider assembly. Figure 2.13-2 Shows spider drum design. Figure 2.13-3 Rotor drum support shelves. Figure 2.13-4 Rotor spider support shelf. Figure 2.14-1 Example flux distribution through pole body. Figure 2.14-2 Shows parts of field pole being assembled. Figure 2.14-3 Shows finished rotor pole end plate with the “L” shaped portio... Figure 2.14-4 Concept of interpolar wedge. Figure 2.14-5 Example of an interpolar wedge. Figure 2.15-1 Copper strap edge bent coils. Figure 2.15-2 Edge bend consequence of gaps between copper segments. Figure 2.15-3 Assembled copper pieces at the jigsaw (interlocking) joint sim... Figure 2.15-4 Brazed jig saw (interlocking) sections and uniform copper. Figure 2.15-5 Shows groundwall insulation, insulating collar, silicone seala... Figure 2.15-6 Shows wedges on pole body to secure copper coil. Figure 2.15-7 Finished field pole with red insulating varnish applied.Figure 2.16-1 Amortisseur bar visible through the pole punching.Figure 2.16-2 Pole under construction with the amortisseur shorting bar show...Figure 2.16-3 Flexible connection between amortisseur circuits on adjacent p...Figure 2.16-4 Shows solid amortisseur connection between adjacent poles.Figure 2.17-1 Brushless excitation.Figure 2.17-2 Traditional rotating brushless exciter with diodes.Figure 2.17-3 Shows modern style constant pressure spring.Figure 2.17-4 Slipring assembly with old style adjustable spring.Figure 2.18-1 Ventilation diagram for a rim ventilated machine.Figure 2.19-1 Rotor centrifugal fan.Figure 2.19-2 Rotor axial fan.Figure 2.20-1 Extra rim laminations at the bottom (colored in red).Figure 2.21-1 Shows a cross section of a conventional two guide bearing gene...Figure 2.21-2 Shows a cross section of an umbrella style generator with one ...Figure 2.21-3 Shows Babbitt bearing pie pieces or “shoes.”Figure 2.21-4 Shows Teflon ™bearing pie pieces or “shoes.”Figure 2.21-5 Shows load cells supporting the thrust bearing shoes.Figure 2.21-6 Shows oil pressure distribution between runner plate and pivot...Figure 2.21-7 Sketch showing oil wedge principle for a pivoting shoe on jack...Figure 2.21-8 Oil pressure distribution between the runner plate for a sprin...Figure 2.21-9 Shows runner plate that sits on top of thrust bearing shoes....Figure 2.21-10 Shows spring assembly to support the shoes.Figure 2.21-11 Shows the bearing shoe installed.Figure 2.21-12 Shows the copper cooling coil at the bottom of the oil reserv...Figure 2.21-13 Shows thrust bearing cooler (extruded aluminum fin CuNi) tube...Figure 2.21-14 Demonstrates the principle of the hydrodynamic wedge in the g...Figure 2.21-15 Typical shaft guide bearing (sleeve type).Figure 2.21-16 Guide bearing shoe in the thrust/guide bearing combination as...Figure 2.21-17 Shows a Babbitt bearing wipe.Figure 2.21-18 Shows another bearing wipe.Figure 2.21-19 Shows what is left of a PTFE bearing when shoe removed and sp...Figure 2.21-20 Bearing shoe with surface abrasion.Figure 2.21-21 Bearing shoe with tin oxide damage.Figure 2.21-22 Bearing that exhibits overheating.Figure 2.21-23 Bearing shoe exhibiting thermal ratcheting.Figure 2.21-24 Bearing show exhibiting oil starvation.Figure 2.21-25 Show exhibiting outer edge Babbitt erosion.Figure 2.21-25 Bearing shows signs of electrical pitting.Figure 2.21-27 Edge load pivoted show showing Babbitt mechanical fatigue....Figure 2.21-28 Edge load journal shell with mechanical fatigue.Figure 2.21-29 Shoe segment showing fatigue.Figure 2.21-30 Shows result of cavitation erosion on the bearing surface....