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26 Cards in this Set
- Front
- Back
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Systems of hydropower station |
a. Hydraulic system: - penstock, valve, spiral case, Turbine, Draft tube b. Electric system - generator, generator wire, busbar, main transformer, high voltage switchyard. c. Mechanical control system - Speed control of turbine; Oil pressure unit; Operating of the valve; Gage lifting; Control of trash racks; d. Electric control system - Excitation system Various related system; Master control room; e. Auxiliary system - Auxiliary power system; Lifting equipment; Oil system; Air system; Water system (supplement and drainage); |
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Buildings of hydropower station |
a. Main Building - upper structure,sub-structure, assembly place(installation, maintenance and repair)
b. Auxiliary building Operating divices,Accessory equipment, Living room,Working place
c. Transformer field: - boost voltage, near the main building
d. High voltage switchyard: - open field, transmit electricity to customers |
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Upper structure |
It consists of assembly layer & generator layer a. Magnetizing system * Generate magnetic （ususally direct current） * Magnetizing exciter: generate magnetic * Exciter panel: control the electricity current |
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Generator type |
a. Horizontal type: small hydropower station b. Vertical type (large hydropower station) * Suspended type - Thrust bearing on the upper bracket. - Low loss in thrust bearing - Convenience in assemblyHigh stability
Disadvantage - Larger upper bracket - Higher unit>150 r/min
* Umbrella type - Thrust bearing on the lower bracket. Advantage - Light upper bracket - Decrease the height(unit and house) - Easy maintenance
Disadvantage - High loss in thrust bearing - Complicate in design and make < 150 r/min |
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Generator pier |
《Support the generator》
Requirement - Enough strength and stiffness - Small amplitude under vibration - Frequency far from the unit |
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Types of generator piers |
a. Cylindrical type * Usually for middle main unitcircle interior, * Circle or octagon outside * Wall thickness larger than 1.5m
Advantage * Excellent under compression and torsion * High stiffness * All concrete
Disadvantage * Narrow internal. * Hard for the installation and maintenance of turbine |
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Types of generator piers |
b. Frame type Usually for small main unit
Advantage * Less concrete * Convenience in installation and maintenance
Disadvantage * Weak in compression and torsionlower stiffness |
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Types of generator piers |
c. Block type * All concrete except turbine well * Usually for large main unit
Advantage * Excellent under compression and torsion
Disadvantage * High stiffnessMore concrete |
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Types of generator piers |
d. Parallel wall type * Made up of two walls * Usually for large main unit
Advantage * Convenience for maintenance * Repair turbine without remove generator |
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Layout of generator |
a. Stator outside * Randomly used today Disadvantage * The space in generator layer is limited * The height in turbine layer is small
b. Stator inside Upper bracket is outside Advantage * Convenience for maintenance of suspended type * Fit for the capacity about 100MW
c. Upper bracket inside Upper bracket is inside Disadvantage * The space in generator layer is enoughWith higher turbine layer |
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Layout of upper structure |
a. Layout of assembly layer * Assembly place * Upper bracket * Lower bracket * Turbine * Turbine cover * Rotor
b. Layout of generator layer(Main building) * Generator and generator hood * Valve hole * Mechanical control machine * Oil pressure unit * Grid( Electric control system) * Air system control room |
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Layout of sub-structuee |
a. Layout of turbine layer * Turbine * Generator terminal load * Oil pressure unit to control valve * Two types of pump: - Maintenance drainage - Seepage drainage
b. Layout of spiral case layer * Water stopping copper * Drainage way for waste water * Two water-collecting wells - One for maintenance drainage - One for seepage drainage |
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Sub-monolith |
a. Penstock b. Spiral case - Steel(water head>40m) - Concrete (Water head<40m) Entrance for repair * Downstream of valve * Upside of spiral case
c.Draft tube * Cone type * Ancon type- half cone part, curved part, diffussion part(rectangle)
d. Valve
* Ball type(high water head) * Butterfly type(low water head) |
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Requirement for valve room |
a. In the main building * The valve must be very reliable, once broken, the water will be out. * The valve room must has water drainage way
b. Arranged outside * Trouble for installation and repair |
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Layout of generator terminal lead |
Requirement: dry, ventilation, heat dissipation, |
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Electric control system |
* Large enough, bright, dry, quiet; * Close to the main building; * Between the main building and the high voltage switchyard; * A cable layer below the central control room; |
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Requirements for the elevation of sub-structure |
* The floor of the generator should be higher than the level of tail water.
* The height of the turbine layer must be larger than 3.5-4 meters.
* It is better to use the same level for the generator layer and the assembly layer. |
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Mechanical control system |
* Speed governor（mechanical hydraulic, electro-hydraulic，microcomputer）
Operation counters；oil pressure unit；servomotor（near stay ring）
* Relief valOperating system of ball or butterfly valvethe oil can be together with the speed governor，or be set individuallyCan be in central control room, or on the spotLift equipment for gate of draft tube: on the spotve: usually controlled by the speed governor of turbine |
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Mechanical control system |
* Operating system of ball or butterfly valvethe oil can be together with the speed governor，or be set individuallyCan be in central control room, or on the spot
Lift equipment for gate of draft tube: on the spot |
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Assembly place |
Usage Installation, maintenance, repair |
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Girder & Crane |
* The girder moves along the longitude of the main building
* The crane moves along the cross direction of the main building |
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The maximum lifting load |
1 Usually the rotor with the shaft
2 Sometimes turbine with the shaft (low head hydropower station)
3 Sometimes the main transformer |
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Bridge crane |
1. Load<75 tons, one girder single crane with double hooks 2. Load>75 tons, one girder with two cranes 3. Hydropower station with more than 6 units, two girders with two cranes 2 girders with 1crane * Light weight, small size * Decrease the height of the upper structure * Convenience in the turnover of equipment
Hard for the cooperative work (disadvantage)
3 girders to 2 cranes * May decrease the height of the upper structure * Increase the installation speed |
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Bridge crane requirement |
Determination of the span With the size of the sub-monolith, on the first stage concrete Try to use the scale given by the machine maker All equipment in the span of the hook The span of the hook is smaller than the span of the bridge crane |
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Location and elevation of assembly place |
Location The assembly place must be placed in the side with the roadElevation * Assembly place = generator layer = road >tail water(common condition) (=(same level), >(above)) * Assembly place = road > generator layer (height increase) * Assembly place = generator layer < tail water road 1: slope road, retention wall 2: slope road, sealing door to prevent flood, closed during flood Other design according to the actual situation |
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Size of assembly place |
*Width: the same with the main building * Length: Determined by the repair of the main unit *Rotor: 1-2 meters space around it*Upper bracket: low weight, large space *Turbine: 1 meters space around it*Turbine cover Usually 1-1.5 times the length of one unit.*Space for the truck Test weight: - 125% of the largest load in static condition; - 110% of the largest load in dynamic condition Repair of the main transformer |
