IEEE 1095:2012 pdf free download – IEEE Guide for the Installation of Vertical Generators and Generator/Motors for Hydroelectric Applications
4.Personnel
lt is essential to have a crew of skilled workers with sufficient helpers and a supervisor experienced in theinstallation of vertical hydraulic turbine-driven generators. In addition to ciectricians and mechanics,workers skilled in pipe fitting, welding, rigging, and winding are usually needed.
In cases where the generator manufacturer is given the job of installing the equipment that they furnish, thegenerator manufacturer will provide a supervisor and all other personnel needed.Otherwise，it isrecommended that one of the generator manufacturer’s field representatives be employed to providetechnical direction of the installation. The representative ‘s familiarity with the construction of the generatorand expcrience in the installation of similar machines are valuable assets.
Close cooperation among the customer，generator manufacturer，exciter manufacturer，turbinemanufacturer，governor manufacturer，and any installation contractors involved is necessary to assureproper installation in the most efficient and safe manner.Agreement of the general procedures to befollowed should be reached before actual erection begins. A leadership position, like a project manager orgeneral contractor，should be assigned to integrate all manufacturers or contractors into a commonschedule.
5.1 General arrangement
The basic elements of the generator (see Figure 1), are the stator (frame,core, and windings), rotor (shaft,thrust block, spider,rim, and poles with windings), thrust bearing, one or two guide bearings,upper andlower brackets (for the support of bearings and other parts)， and soleplates，which are bolted to thefoundation and form supports for the stationary parts of the machines. Other components may include adirect-connected exciter or starting motor，rotor brakes or combined brakes and jacks，foundation bolts,platform, stairway and handrails, and an air-discharge housing or a totally enclosed ventilating system withsurface air coolers.
The thrust bearing can be located above or below the rotor. When only one guide bearing is utilized, it isnormally located near the thrust bearing. When two guide bearings are used, one is located above and onebelow the rotor. A generator with the thrust bearing located above the rotor is referred to as a suspendedgenerator (see Figure 2). A generator with the thrust bearing and a single guide bearing below the rotor isreferred to as an umbrella generator (see Figure 3). An umbrella generator with a second guide bearing isreferred to as a modified umbrella generator (see Figure 4).Standard IEC 60034-7 depicts otherarrangements according to the general unit arrangement and the split of scope between generator andturbine.
The upper bracket is supported from the stator frame and occasionally requires radial restraint by thegenerator enclosure or by the foundation when additional stiffness is required.On small generators withtheir thrust bearing above the rotor, the lower bracket may be integral with, or bolted to, the stator frame.Otherwise, the lower bracket is supported on its own set of soleplates.
The stator winding may consist of single- or multi-turn coils or half-turn bars. Double-layer windings,having two coil sides per slot, are most commonly used. The coils or bars are secured in the stator slots bywedges driven in grooves located at the top of the slots and by side-packing provided separately orintegrally with the coil or bar. End windings are braced to restrain movement due to short circuits and toprevent possible downward movement of the stator coils or bars. Temperature detectors are generallyinstalled between coils in a selected number of slots to indicate the temperature of the winding duringoperation.