modern DC field breaker.Figure 10.1-3 Shows an AC field breaker.Figure 10.1-4 Shows one style of shunt on the field bus inside field breaker...Figure 10.1-5 Shows schematic of excitation system with field discharge resi...Figure 10.1-6 Shows typical discharge resistor inside field breaker cubicle....Figure 10.1-7 Shows another typical field discharge resistor.Figure 10.3-1 Shows brushless exciter diode end.Figure 10.3-2 Shows brushless exciter bus end.Figure 10.5-1 Shows armature commutator, brush assembly, risers, dust, and o...Figure 10.5-2 Shows close up of exciter stator (stationary part).Figure 10.5-3 Shows armature coil connections before brazing or soldering.Figure 10.5-4 Shows brazed connections from armature coil to risers.Figure 10.5-5 Shows the stator winding in good visual condition.Figure 10.5-6 Shows a failed exciter stator winding.Figure 10.5-7 Shows exciter interpole winding.Figure 10.5-8 Shows exciter armature (rotating part) out of stator.Figure 10.5-9 Shows exciter mounting bolt for the commutator assembly.Figure 10.5-10 Shows commutator brush rigging that can be rotated circumfere...Figure 10.6-1 Shows metallic particles inside the slipring helical grooves....Figure 10.6-2 Shows same contamination from slipring on copper bus.Figure 10.6-3 Shows a good commutator surface film.Figure 10.6-4 Shows good clean split brush that is in good condition and pro...Figure 10.6-5 Shows brush that is not properly seated.Figure 10.6-6 Shows streaky commutator.Figure 10.6-7 Shows threading on the commutator.Figure 10.6-8 Shows example of a grooved commutator.Figure 10.6-9 Shows bar edge burning on the commutator.Figure 10.6-10 Shows slipring in good condition.Figure 10.6-11 Shows slipring burned after a failure and severe damage to th...Figure 10.6-12 Shows close up view of slipring damage where brush surface re...Figure 10.6-13 Shows typical slipring insulation configuration.Figure 10.6-14 Illustration showing the difference between a “U and V” shape...Figure 10.6-15 Shows commutator bevel on the copper bars.Figure 10.6-16 Shows typical slipring brush gear arrangement.Figure 10.6-17 Shows approximate relationship of safe brush operation.Figure 10.6-18 Shows broken strands on brush shunt.Figure 10.6-19 Shows old style commutator springs.Figure 10.6-20 Shows old style slipring springs.Figure 10.6-21 Shows modern style commutator springs.Figure 10.6-22 Shows modern style slipring springs (same spring as in Figure...Figure 10.7-1 Shows significant scale buildup restricting water flow.Figure 10.7-2 Shows the water box open on a surface air cooler.Figure 10.7-3 Shows cooler tubes that are damaged.Figure 10.8-1 Shows a heat activated device mounted above the water deluge r...Figure 10.9-1 Shows one style of shaft grounding brush.Figure 10.9-2 Shows missing bolts on frame member for upper covers.
11 Chapter 11Figure 11.1-1 Shows knife test at the back of the core.Figure 11.1-2 Shows radial and tangential measurement probe locations.Figure 11.2-1 Stator core fault current path.Figure 11.2-2 Shows a block diagram of the ELCID setup.Figure 11.2-3 Shows multiple loops of wire on the stator as part of the ELCI...Figure 11.2-4 Setup for ELCID testing.Figure 11.2-5 Shows the ELCID potentiometer basic circuit.Figure 11.2-6 Shows the Chattock Potentiometer on the stator core.Figure 11.2-7 Flux test cable forming the loop or rings wrapped around the s...Figure 11.2-8 Shows repaired core ready for the high energy flux test.Figure 11.2-9 Shows a thermal scan of Figure 11.2-8.Figure 11.3-1 Shows manual method of checking wedge tightness with a small b...Figure 11.3-2 Shows automated wedge tapper on the stator core.Figure 11.3-3 Shows the wedge map produced by the software.Figure 11.5-1 Shows a perfect semiconducting (black) and stress control (gre...Figure 11.5-2 Shows interface damage and resulting partial discharge activit...Figure 11.5-3 Shows interface with advanced severe deterioration.Figure 11.5-4 Shows another example of severe damage to the interface area....Figure 11.5-5 Shows the coil ready for the black semiconducting paint applic...Figure 11.5-6 Shows the black semiconductive paint applied to the coil and t...Figure 11.5-7 PD testing by capacitive coupling – offline.Figure 11.5-8 Shows PD summary values.Figure 11.5-9 Shows classic PD patterns.Figure 11.5-10 Shows TVA probe for use on the stator slots.Figure 11.5-11 Shows ultrasonic probe with headphones to detect PD.Figure 11.5-12 Equivalent circuit showing the four currents monitored during...Figure 11.5-13 Insulation resistance measurements at 5 kV for same machine b...Figure 11.5-14 Measured current for a generator with a strong influence of t...Figure 11.5-15 Types of currents for an epoxy‐mica insulation with a relativ...Figure 11.5-16 Temperature correction factors for “Thermoplastic” (asphalt) ...Figure 11.5-17 Polarization index curves for insulation resistance as a func...Figure 11.5-18 DC ramp test plot.Figure 11.6-1 Crack in spider arm support ledge clearly visible by the naked...Figure 11.6-2 Shows a magnetic particle indication of a crack.Figure 11.6-3 Shows phased array approach to crack detection.Figure 11.6-4 Shows FEA results outlining the pole attachment high stress ar...Figure 11.6-5 Shows FEA results outlining the rim attachment high stress are...Figure 11.6-6 Shows increased radius in the rim section to alleviate the str...Figure 11.6-7 Shows increased radius in the pole section to alleviate the st...Figure 11.6-8 Shows machining of the pole attachment area.Figure 11.6-9 Shows on‐site machining of the rim attachment area.Figure 11.6-10 Shows spider arm and welds to check with NDE.Figure 11.6-11 Shows spider hub and which welds to check with NDE.Figure 11.6-12 Shows shelf crack and where UT should be positioned.Figure 11.6-13 Shows one style of rotor fan for NDE of welds.Figure 11.6-14 Shows another style of rotor fan for NDE.Figure 11.6-15 Shows drum assembly with disks and vanes.Figure 11.7-1 Shows horseshoe style field coil interpole connectors.Figure 11.7-2 Shows rotor leads fastened to the rotor structure.Figure 11.7-3 Shows schematic setup for a impedance (VIW) test.Figure 11.7-4 Shows examples of a tested pole with no shorts.
12 Chapter 12Figure 12.5-1 Shows two capability curves – original in red and uprated in b...Figure 12.5-2 Shows uprated capability with new higher power factor.Figure 12.6-1 Schematic of the static pilot and rotating exciters.Figure 12.6-2 Shows architecture of a rotating brushless exciter with diode ...Figure 12.6-3 The original exciter stator void of all old poles and interpol...Figure 12.6-4 Newly manufactured field poles on the original stator exciter ...Figure 12.6-5 Shows completed exciter stator.Figure 12.6-6 Shows the original armature with the commutator removed and a ...Figure 12.6-7 The exciter armature in final phases of winding assembly and d...Figure 12.6-8 Shows the completed exciter armature.Figure 12.6-9 Shows thyristor arrangement in the architecture of the exciter...Figure 12.6-10 Shows new brushless exciter with thysristor technology.Figure 12.6-11 3D model of the exciter stator in Figure 12.6-10.Figure 12.6-12 Sectional view of the rotor assembly.Figure 12.6-13 Shows difference in response times for diode vs thyristor/sta...Figure 12.6-14 Shows de‐excitation rate between diode, static, and thyristor...Figure 12.6-15 Shows transceivers inside exciter housing.Figure 12.6-16 Shows the conversion schematically from thyristor to diode mo...Figure 12.6-17 Typical static exciter schematic.Figure 12.6-18 Shows a simplified diagram of the static excitation system....Figure 12.6-19 Typical static exciter on the right and exciter transformer o...
Guide
1 Cover
2 Table of Contents
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