06/10/2011 G.J. de Vilder

STX 93 Generator design & assembly

AnAnAnAn electricelectricelectricelectric tensiontensiontensiontension U is U is U is U is inducedinducedinducedinduced in a conductor in a conductor in a conductor in a conductor accordingaccordingaccordingaccording FaradayFaradayFaradayFaraday ssss lawlawlawlaw::::

UUUUindindindind = = = = ---- B B B B l l l l vvvv

WithWithWithWith::::UUUUindindindind ==== induceinduceinduceinducedddd voltage [V]voltage [V]voltage [V]voltage [V]BBBB = the = the = the = the magneticmagneticmagneticmagnetic fielfielfielfield d d d [[[[teslateslateslatesla]]]]llll = = = = the the the the lengthlengthlengthlength of the conductor [m]of the conductor [m]of the conductor [m]of the conductor [m]vvvv = the speed of the conductor w.r.t. the = the speed of the conductor w.r.t. the = the speed of the conductor w.r.t. the = the speed of the conductor w.r.t. the magneticmagneticmagneticmagnetic field [m/s]field [m/s]field [m/s]field [m/s]

Since Since Since Since vvvv = = = = ωωωω RRRR=>=>=>=> UUUUindindindind = = = = ---- B B B B l l l l ωωωω RRRR

With:With:With:With:ωωωω = angular speed [= angular speed [= angular speed [= angular speed [----/s]/s]/s]/s]RRRR = = = = airgapairgapairgapairgap radius [m]radius [m]radius [m]radius [m]

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1.1.1.1.Basic physics of a generator& consequences of thisBasic physics of a generator& consequences of thisBasic physics of a generator& consequences of thisBasic physics of a generator& consequences of this

UUUUindindindind = = = = ---- B B B B l l l l ωωωω RRRR

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1.1.1.1.Basic physics of a generator& consequences of thisBasic physics of a generator& consequences of thisBasic physics of a generator& consequences of thisBasic physics of a generator& consequences of this

Nedwind 62 1MW LW 52 750kW STX72 2MW STX93 2MWGeared Asyn gen DD EE syn gen ABB DD PM gen STX DD PM genYr of comm: 1999 2000 2010 2011

12 years of Dutch industry windturbine design

1.72.42.8158.5ωωωω angular speed [/s]

0.8651.30.411.45length of a single conductor l [m]

2.491.752.450.35R airgap radius [m]

permanent magnetpermanent magnetelectricalelectricalexitation

synchronous DDsynchronous DDsynchronous DDgeared SQI asynchronous generator type [-]

16.522.526.518rated speed [rpm]

220.751power [MW]

2011200320001998year of commisioning

STX93Z72 ABBLW52-750NW62WT type

1.001.171.611.27rel.mass/torque [-]

5.563.995.621.06outer diameter [m]

1.000.860.390.58rel.mass [-]

57000490002200033000entire drivetrain mass [kg]

1.000.740.240.46rel.torque [-]

permanent magnetpermanent magnetelectricalelectricalexitation

synchronous DDsynchronous DDsynchronous

DDgeared SQI asynchronous generator type [-]

1249921300570torque [kNm]

0.930.920.900.93gb x generator x converter efficiency [-]

16.522.526.518rated speed [rpm]

2.002.000.751.00power [MW]

2011200320001998year of commisioning

STX93Z72 ABBLW52-750NW62WT type

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2. Composition of the generator

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2. Composition of the generator

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2. Composition of the generator

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3. Assembly of the STX93 generator

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-Finally the heat run

4 Test of the generator4 4 Test of the generatorTest of the generator

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4 Test of generator (temperature distribution)4 4 Test of generator (temperature distribution)Test of generator (temperature distribution)

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-after 20 hr full load on temperature

-max temperature: 25C below limit

-ambient temperature: 30C

4 Test of generator (Results)44 Test of generator (Results)Test of generator (Results)

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5. Construction of the STX93 (final lift)

v avg at hub Output STX93[m/s] [MWh/yr] 95% availability

6 46266.5 5417

7 61637.5 68478.5 7984

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5. Cost of Wind ���� other energy generation methods [$/MWh]

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5. Potential contribution of STX93 for NL energy demand

Electricity consumption per home/yr [MWhr] 3.35people/home[-]: 2.3NL inhabitant # [-]: 16000000Total energy consumption all homes in NL [GWhr]: 23304State of art WT energyproduction/jr [GWhr] 6required # WT [-] 3884rate of demand of homes to total demand [-] 0.25

installed # of WT (2009 CBS; senternovem) 1873estimate Q2 2011 1967

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NL Windmap:

Only WT installations alongcoastal area s (2000 #)

No installations in centre & mid east & mid south area

Population density in red . is similar or less; therefore2000 additional STX93 WT, could be placed here & in case all WT are existingWT s are replaced bySTX93, 100% of energy of homes can be supplied byWind (= 25% of total, onshore)

5. Potential contribution of STX93 for NL energy demand

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6.Future developments (for DD)

24.3%4.0%PM cost / WT cost price

48000055300072600total PM cost [Eu]

115.215.1PM price [Eu/#]

48004800# of magnets [-]

0.72Euro to Dollar

16021PM price [USD/#]

increase in cost price [Eu]Jun-11Feb-10

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6.Future developments

geared <=> DD w.r.t. efficiency

86.0

88.0

90.0

92.0

94.0

96.0

98.0

0.0% 20.0% 40.0% 60.0% 80.0% 100.0% 120.0%

partial load level [-]

effi

cie

ncy

[%]

3 stg gear + PM1000rpm

2 stg gear + PM450rpm

0 stg gear: DD PM15rpm

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Conclusions

1. Permanent magnets did contribute to significant increase of efficiency of wind turbines

2. At the same time the drive train mass (+tower topmass) could reduced significantly with gearless PM generators

3. Actual price level does give DD PM wind turbine suppliers a difficult position to realize profits with their product

4. Putting a 2 or 3 stage gear box in between the rotor and the generator is with current PM prices a method for improved cost-effective application of permanent magnets in generators

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Questions?