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User Manual
) y0 E6 E0 {8 l9 n1. INTRODUCTION 1
: O; ~$ W" I) U+ ~( t1.1 Installation 1
- o4 \! J2 N" N" J# `5 t1.2 GH Bladed modules 2 # V9 t& N2 L. N
1.3 The GH Bladed Educational version 2 . A: s! y8 ?( Q: I1 T& A" O( G
1.4 The GH Bladed Demonstration version 3 ' V. e' F1 O2 J
1.5 Support 4 : b) A9 K7 e+ U- [
1.6 Documentation 4
, a" b0 [8 i/ R. `- j2 j5 m5 F9 h7 K/ q1.7 Acknowledgements 4
# z" G0 ] B/ r0 W8 ]( F2. USING GH Bladed 5 5 z, Y s; B" \) T% T
2.1 General description and layout of the user interface 5
3 E7 L$ M9 s) |& F5 x, g4 f2.1.1 Main toolbar - pull-down menus 5
2 n [/ |+ E' B2.1.2 Toolbar icons 6
! w( c. E2 V1 s% D3 ^" n0 z2.1.3 The calculation window 7
6 U6 @9 D7 L) q8 w2.1.4 Sequence of operations 7 0 S- ?/ f/ d: |$ ]0 Y
2.2 Entering data 8 ) Q& V* m8 N3 q; U9 c
2.3 Using project files 8
" p" M- E. Q/ X2.4 Performing calculations 9
]& s+ |9 M, A2.5 Viewing results 9 6 e$ K# J0 X' f+ N/ _
2.6 Compiling reports 10
8 ?4 k Y4 C# s: \; m5 A) A2.7 Data Encryption 10 3 n5 x& @7 }6 ^7 l% k
2.8 User preferences 11
! T8 A3 i1 f$ ~6 L3 K, d! X4 j2.9 Context-sensitive help 11 & x/ ^2 A5 Y; K6 x0 R- t+ W$ M
2.10 Dongles 11 0 `7 S r0 m' d+ n$ F5 h) e! Z$ Y
3. DEFINING THE TURBINE BLADES 13
: F+ y% S1 W- |* g3.1 Choosing blade stations 14 s; [5 K! b7 |$ \
3.2 Blade geometry 15
2 w- X0 k" K$ ]# J5 g6 a3.2.1 The blade reference plane 15 - {$ f/ v, B0 O3 `# Q% r
3.3 Blade mass distribution 16
5 P4 G8 B$ n. m) t3.3.1 Distributed mass 16 " C& j6 u s6 e
3.3.2 Point masses 16
: e& [2 K5 c3 ?: s& N8 p3.3.3 Vibration dampers 16 ( T/ f' P; @( Q! a
3.3.4 Blade icing 16
* e5 L, m4 I8 n D7 T {7 M3.4 Blade stiffness distribution 17 7 c0 y3 C' k, u) F
3.5 Flap-Twist Coupling 17 3 Z# ~0 Q9 t m& ~& H& \9 u
3.6 Aerofoil sections 18
8 o+ `, i8 P& D. U3 c9 w) a3.7 Aerofoil datasets 19
* [! C0 R8 g* D9 V' a3.7.1 Defining aerofoil datasets 19 2 }( a) V! o4 w( L7 T6 Q1 Y
3.7.2 Importing a dataset 19
. P+ j: g4 L# ~+ o o; A0 |: r q2 _3.7.3 Adding a new dataset manually or via the clipboard 19 + t- {! N+ d4 t- {9 j: ?
3.7.4 Editing an existing dataset 20
/ f8 M' Q5 E' M# j9 M+ S3.7.5 Removing a dataset 20 * V* h4 x2 d7 W( u
3.7.6 Viewing aerofoil data graphically 20
( ^5 S8 B4 p% q/ N7 A3.8 Format of ASCII aerofoil files 20
3 J2 T$ ^7 b1 f. s3.9 Defining normal aerofoil sections 21
% a |6 o* F6 n2 W1 s0 z0 J1 D9 V* ?3.10 Defining aileron sections 22 ) y- J& W3 Y# i1 n
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, l5 z9 Z$ R; ]9 k6 s9 f ^4. DEFINING THE REST OF THE TURBINE 24
8 f$ i9 ]( w; v# ]: L# ^/ X3 z& z4.1 Defining the rotor 24 $ w7 L, I2 x, D- c t
4.2 Defining the hub 25 1 T9 u9 a' T0 r3 ?- Y1 @
4.3 Teeter restraint 26
. H0 t4 R6 J8 v" A; \4.4 Defining the tower 26
( p* p7 c' e, [; ?2 I$ o4 d4.4.1 Monopile Tower 26
4 P; o T; U' P1 M+ t4.4.2 Multi-member tower 27
: ~) n$ G) s3 w: D4.4.3 Flanges and point masses 28 & a% a8 ]" P+ V5 s. f
4.4.4 Vibration dampers 28
_; k5 T Y; _9 E9 u4.4.5 Environment 28 : I: `3 q- |5 F2 G# A; Y- e$ k6 n# Y; h
4.4.6 Foundations 29 # q4 j1 y7 i" k5 r5 J! p
4.5 Defining the power train 30 4 f! t% U# v/ s) ^8 T m
4.6 Transmission 30 3 Z3 E# H8 ?6 n, M
4.6.1 Locked speed model 31
) g# P9 L+ i- g0 r( d4.6.2 Dynamic model 31 # f, l, }5 a: W) I. }: B
4.6.3 External DLL for transmission dynamics 32 7 Q3 V4 T+ E6 b3 q# O% T
4.7 Drive train mountings 32
& w2 d8 D( Z( U% G4.8 Generator 33 ' X5 U9 U3 |5 d6 ^
4.8.1 Induction generator 34
+ s& s& l+ i; W3 k% m1 C4.8.2 Variable speed generator models 35 B# @/ ~1 y4 K, W: E
4.8.3 Variable speed mechanical model 35
- u, K/ [( N3 \0 p9 A& u9 j( A4.8.4 Doubly fed induction generator model 35 . p5 I' \+ d& Q* A$ `. l
4.8.5 Synchronous generator with fully rated converter 36
E3 W* c9 J; O3 V' I) g4.8.6 Variable slip generator 39 0 |: P3 v8 h* S( y) e+ R# T
4.8.7 User-defined generator model 39
+ ~7 C F# ^6 b- c4.8.8 Drive train damping feedback 40
8 l9 ^: `" m: [) d* S4.9 Energy losses 40
( p$ V3 j8 n' m8 ]8 O7 Y( S1 T" C4.9.1 Mechanical losses 40
& v. p3 \. n8 N4.9.2 Electrical losses 41 4 R5 `6 u# n; \; t+ R+ p2 U
4.10 The Electrical Network 42 ! H4 w8 P6 u0 e% w- t/ K- U
4.11 The nacelle 42
6 y' o! P0 ~8 J2 v8 r& M. m, Z# `5 F5. CONTROL SYSTEMS 44 5 m) K# m f' L3 g
5.1 Fixed Speed Stall Regulated Control 45
# i p2 o" W" b1 Q% D# [/ D5.2 The fixed speed pitch regulated controller 45
7 _0 B2 N# ~# x+ P8 r# H" G5.2.1 Steady state parameters 45
0 G' k1 O o( K$ i) _5.2.2 Dynamic parameters 45
5 g- z$ z5 D R! j( X" N$ o1 W5.3 The variable speed stall regulated controller 46
2 S0 E. i# k/ N5.3.1 Steady state parameters 46
2 C( e; M& k2 k5.3.2 Dynamic parameters 46 ! S, T) Y8 {* c) P
5.4 The variable speed pitch regulated controller 47
; R: [( y& q, @# |+ x! c5.4.1 Steady state parameters 47
+ p3 Q5 l2 f I; Y5.4.2 Dynamic parameters 47 3 _" l# \: x8 t' {2 d" W
5.5 PI control 48
( F2 o/ W$ F0 L# S% F5.6 Gain scheduling 49
4 v: Q2 U" R6 l8 g7 d0 u' U- _' x5.7 Variable speed control below rated 50 . q1 u! f' X. T6 J8 q: T! B" V1 v1 C' g
5.7.1 Optimal tip speed ratio 50
% y! t; c9 D! Q; B7 Q. J2 r5.7.2 Look-up table 51
- V6 n" \7 p8 c* F5.7.3 Other parameters 51 1 ?3 [( n* m, X# J' f' h
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5.7.4 Control in the variable slip case 51 " O. L. J$ }0 Q* f& ~* D$ W& ]- A
5.8 User-defined controllers 51 6 M/ j& f6 M' z# ~; w N' b. w; `
5.8.1 Writing a user-defined controller as an executable program 52
# R3 `( b' F k+ M$ K, c- _' H5.8.2 Writing a user-defined controller as a dynamic link library 53
# I6 l) B3 w! s. Q' x, ~5.8.3 Using a user-defined controller 54 8 l4 v$ O& m+ b. e& Z
5.8.4 Signal noise and discretisation 55
2 G2 n2 C1 f) {2 `) ~5.9 Transducers 55 ' Z+ a* a9 N6 D$ u) ?1 B' f F
5.10 The pitch actuator 55 + D+ m( L. [5 X( G; L
5.10.1 Passive dynamics 57 % n: V( G3 J/ C/ X
5.10.2 PID parameters 57
8 p' S3 P" F+ f2 U& t3 a5.11 The shaft brake 58
3 `7 Y% j3 p: Z9 g& N3 z6 [9 u5.12 Start-up sequence 58 4 a- X3 t$ p- V" D* h6 ]& L5 [% N
5.13 Normal stop sequence 59 8 l2 q+ r% _. p+ j( E
5.14 Emergency stop sequence 60
1 Y p# c$ j+ @: U3 }3 Y- \1 M" w5.15 Idling conditions 60 ' q+ z9 }( {2 W6 O$ T
5.16 Parked conditions 60
; P# Y, a) x5 h/ o$ I" X5.17 Yaw control 61
+ [7 x7 i9 u8 p2 ]5.17.1 Yaw Dynamics 61 7 L% g; Z2 J4 v, ~
5.17.2 Active Yaw 62
R- i) l/ G8 \% k- Q5.18 Safety System 62
4 `; g; P w/ O' c4 N5.18.1 Safety System Circuits 62
. K( o2 m# K/ r4 I5.18.2 Safety System Pitch Action 62
. A% @! }, v0 a5.18.3 Safety System Trips 63
3 o0 a/ \& K0 C: U4 C. q6. DEFINING THE ENVIRONMENT 64 / S$ U1 z, Q6 [$ `
6.1 Defining the wind 64 $ j& O/ C! X! }+ v8 K: [
6.2 Wind shear 65 : [! A- {( }" ^) I" }! p' U
6.3 Tower shadow 65
% s6 b, w6 V" x% [; L/ g$ a6.4 Upwind turbine wake 66
8 X5 N2 S3 ]1 E& m5 S! T- U4 ?6.5 No time variation of wind speed 67 : p1 F0 t& }) \3 H Y& s( }
6.6 Single point wind history 67 9 T1 {- @1 U# V( h" o3 S
6.7 3D turbulent wind 68
|! U& Q7 H* \+ c' b6.8 Transients 69
# P' C1 S1 C- E5 P3 t9 E# A7 \5 n6.9 Definition of wind direction 71 " d5 B+ {+ S3 \" R$ B2 c" z U
6.10 Generating turbulent wind fields 72
2 y8 \; ^# _9 r" b6.10.1 Defining turbulence characteristics 72
& D6 t. J8 j6 n- V8 ~6.10.2 Advanced options 73 $ X- Z7 B' R- Y( w+ T) C# s
6.10.3 Generating the turbulence field 74
: R4 D- W6 A0 P6.11 Annual wind distribution 75
( Y7 ?' M' {- i. \2 K6.12 Defining Waves 76
, Z0 `; N5 ?. `, q# d9 b6.12.1 None (no waves) 76 $ g3 A q, i4 u6 M$ n
6.12.2 Irregular waves 76 $ X5 X. A7 T' T; H% \$ G
6.12.3 Constrained waves 77 % U' k9 {! l2 Q9 k
6.12.4 Regular waves 77 $ s1 Y4 G( M; I# o( P
6.13 Defining Currents 78 9 I8 [5 w9 l" N% | y
6.13.1 Near-surface current 78 7 A( d4 b1 n6 v: I; t* s3 y
6.13.2 Sub-surface current 78
$ Z: k. f* M# o# a& [! W# Z' K& @6.13.3 Near-shore current 79 7 Q. g7 A( U* Z) c! @ _8 ?
6.14 Tide height 79 1 d z* r5 ^0 ]. w7 O" V
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" l; d! M( E) W. Z# h* z" }' } z6.15 Scatter diagram 79 w" g5 A7 [! V/ B, i% ^
6.16 Earthquakes 80 2 g' j/ v! J) u( @+ z, b
6.16.1 Generating earthquake time histories 80
$ @* t, F# E5 h1 V) `- B7. EXECUTING WIND TURBINE CALCULATIONS 82
' G8 e4 W3 J# b, x: S" _5 k7.1 Modal analysis 82
6 K2 K% U( N; |6 m# A! Q7.1.1 Defining the modes 82
2 y/ n4 M- R+ Y" v# d- ~3 C" w3 }9 F7.1.2 Performing the calculation 83
# ^+ \+ P) W9 O1 a5 N+ _0 ~$ F5 S7.1.3 The modal frequencies 83
3 [6 B! }8 Y4 u) y3 D7.2 The calculations screen 83
# m# f( k; P: V" R- g5 y$ ]7.2.1 Calculations available 84 6 m& w/ n5 X g9 ]7 X% Y
7.2.2 Data required for calculations 84 ! r/ D8 F) |$ n; x/ s/ _
7.2.3 Calculation options 84
0 ~+ K' W1 E+ F8 y- M) o7.2.4 Specifying outputs 84 8 d7 e1 ?& y6 M, [/ a6 i6 [
7.2.5 Calculation parameters 84 1 \! B& L5 T& g* [4 z
7.2.6 Executing a calculation 85 # z7 b, n4 i3 n( P8 p
7.2.7 Batch processing 85
! C" d) q; h4 k1 G7.2.8 Retrieving calculation details 87
! r. Y- z% Y4 e* C8 `+ o+ R9 C7 X7.3 Steady calculations 87 # z, a# p1 Q* ^. ^$ z
7.4 Simulations 88
* ^* S1 _1 w$ n9 `) x7.5 Calculation parameters 88
% ~, E' n# G3 t/ w. N( a7.6 Aerodynamic information calculation 89
% q0 t7 r: N3 _* B5 g, Q7.7 Performance coefficients calculation 89 : X5 r$ A4 X; T/ X9 c
7.8 Steady power curve calculation 90
2 X0 ?: c# u3 c: m/ X7 U- D7.9 Steady operational loads calculation 90
8 p) h- Q; v; y! p6 J" ^8 `7.10 Steady parked loads calculation 91
. D7 F$ n6 P- x2 C3 g/ F; Z% o7.11 Model linearisation calculation 91
: ?) R/ I; a5 F b B, Z- ~0 S ]7.11.1 Selection of model features for linearisations and Campbell diagram 92
0 o3 y2 T3 K1 f) G1 h: Z7.12 Pitch and speed schedule 93
. O! m9 m5 j1 J V) c7.13 Simulation control 93 " |8 }1 F" d# v9 T; b" p" ^& v
7.14 Initial conditions 94
6 l; N) v( M$ K0 W$ C( ~- p7.15 Hardware test simulation 94
8 p1 r8 u* U8 B3 a7.16 Aerodynamic models 95 & ^) Q" F( k& Z! Y$ `* H6 w+ z
7.17 Physical constants 96 $ v! u& A& c9 l$ ]
7.18 Safety factors 97
: X# K$ h! r3 H0 w+ U1 E R7.19 Imbalances 97
, A1 p/ ], Z5 r% S4 `2 S9 V8 m7.20 Turbine Faults 97
7 ?% |# P% @4 M' I u7.20.1 Pitch faults 97
, t4 d' M1 ?+ ]8 S. _3 f" R0 s7.20.2 Generator and network faults 98 3 b- M4 B5 v# O9 z
7.20.3 Yaw faults 98 # m: [. G) A* B+ m1 Q6 x# n: J
7.20.4 Transducer faults 99
( M4 U- U! p& F/ U7.21 Controlling the calculation outputs 99
1 B7 x- i9 X, b1 h' d: y+ w) H7.21.1 Blade outputs 99
8 F" T1 ]7 X6 b5 V7.21.2 Tower outputs 99
2 k" d: A+ f* @' s, u/ D7.21.3 Other outputs 100 8 N V1 Z& V! Z% O# E
7.21.4 Co-ordinate systems 100
3 Z3 D* N" x) ?7.21.5 Exceptions to the use of the ‘GL’ co-ordinate system 103
3 }- f. c# P5 |' ^7.21.6 Refinement of deflections and loads 104
9 d p& ?3 r0 I9 K7 M# `# a* b7.22 Specifying calculation options 104
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" [( i0 g% Y4 [+ a7.23 Multiple calculation setup 105
1 Q- u5 b/ k' ?1 U0 ^7 W; q8. POST-PROCESSING 107 # X$ k' Z L+ |) a
8.1 Basic statistics 107
4 {. ~8 |) E0 o N* [! T8.2 Fourier harmonics 108
. K7 V9 }% \0 a& a2 N$ c9 H: w8.3 Periodic components 108
8 \4 P; X8 b& K' L3 S8.4 Extreme predictions 108 9 j- @' a0 d, t) u
8.5 Auto spectrum 109
& m: [$ F" B7 |) p8.5.1 Options for spectral analysis 109
6 ?# A n1 b* ~8 s3 B8.6 Cross spectrum 110 " P' E1 S( r" g& x0 B$ e" y
8.7 Probability density 110
/ m7 t* _6 _* y! j- {. r6 j8.8 Peak value analysis 111
* a6 L" [' z, V" X4 O8.9 Level crossing analysis 111 # @1 A/ S9 M6 K" v+ T& |9 E
8.10 Rainflow cycle counting 112
- r1 E+ J5 u! c/ j1 W6 h2 f8.11 Fatigue damage estimation 112
! `; i: l8 K" I) |9 H4 ]7 w" I3 g8.12 Setting bin limits 113 0 o% X, J# H8 ^" M4 J) V1 d! E
8.13 Annual energy yield 113 1 Y' ^- k6 w X+ Y1 O
8.14 Channel Combination and Tabulation 114
2 A1 q5 B! T: F8.14.1 Multiple processing option – Channel combination 115
2 S6 b" F" f0 w2 B# T) G2 {8.14.2 Multiple processing option - Tabulation 115 % C: Q8 o+ G y% o5 J1 b
8.14.3 Multiple processing option – Matrix combination 115 6 G5 G: }0 w& i* V1 E
8.14.4 Multiple processing option – Old Style channel combination 116 ; w' e2 K; o7 B1 c4 {% u' N5 M
8.14.5 Single channel combinations 117
$ f: r$ ? R$ G! Q( M! Q8.15 Multiple Processing 117
# J* @8 V6 m2 i9 b; T7 S0 U0 G& f3 j8.16 Ultimate Loads 118
W' \2 c" Q# I9 k- C- H2 t' Q) M3 x8.17 Ultimate Load Cases 119 - G' ^! B3 Z$ y5 Y9 h1 ^; c+ v
8.18 Flicker 119
. v. `0 \6 M% v6 M% j8.19 Linear Model 119
: l; e: X. I. u$ p1 n) j3 O8.20 Extreme load extrapolation 121
: [ Z! i0 ?0 ]: v5 p) a8.21 Data channel selection 122
/ t* h2 Q0 I4 n* B& P) P" ]; P8.21.1 Selecting independent variables 122 5 T. S& l. ]2 z
8.21.2 Messages and further information 122
& r' O/ f8 _" v! f2 T+ n" u8.21.3 Deleting information 122
9 m8 C C6 t+ {, i5 C$ W9. GRAPHICAL DATA VIEW FACILITY 123
* K4 j {, v0 G% S! Z" r9.1 Graphs of several variables 123 " c) U: b0 M5 R7 _; M
9.2 Graph styles 123 / b3 g# V( f1 l
9.3 Grids and logarithmic axes 123 4 @! Y% t1 o- |1 @: j9 R3 M J
9.4 Units 124 . w" ^0 w1 }" z1 @ }
9.5 Axis limits 124 5 Y9 s2 k* |4 H/ C/ T% V5 z- J8 R
9.6 Graph titles 124
1 L& }0 O. B$ k5 h$ F9.7 Graph legends and line styles 124
2 I9 j' Y, o1 E$ M9.8 Cross-plots 125
* P9 h; x" s- t; }( L; I8 D, u9.9 Tabular output of results 125 , q0 b! M/ F( T' z
9.10 Refreshing graphs 125 6 T6 Q/ T! _- h s! w
9.11 Graph configurations 125 . X( C' _: d! B! c$ D7 d" ^
9.12 Multiple Plotting and Tabulation 126 1 Q/ }% p6 H |( x
9.12.1 Graph configurations 126 e0 r% E8 _8 a7 C! v8 W
9.12.2 Replacing variables 126 1 @. {( K G c1 ]3 |8 P4 ?, @7 c
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9.12.3 Replacing runs 126
: W6 F' \2 g F" \7 L9 D$ J9.12.4 Sequence Control 126
$ y8 m* ~8 ?' [) o5 n% |9.12.5 Tabulation of Ultimate Loads 126 # T6 f5 n2 A/ c9 G$ t g( q
9.12.6 Output 126
Q+ d. s, x2 ^' R2 O S: r, n10. REPORTING 128 $ w9 q8 E3 F" j' F& j \1 k+ Y
10.1 Project reports 128 # I* h2 d" \- ?3 ~# t
10.2 Calculation reports 128
( [2 L) A; w4 p2 N& ]10.3 Adding calculation results to a report 129 0 k1 l/ N1 y9 R+ u1 N- B
10.4 Editing and printing reports 129 , V9 P7 Y S5 x, J4 V4 w2 o* E
10.5 Linked graphs 129 6 x6 \; m( B- I* L) I# M+ E% f
11. THE WINDFARMER LINK MODULE 130 ( x' E j; q# C9 g( |
11.1 The GH Windfarmer output file 131 0 \0 w( r3 l9 x1 l' u
11.2 The wind file template 135
. }/ ?; `" |& {0 F11.3 The turbine model template 135
" i- o' t( H+ N* H- O$ t- Q11.4 The fatigue processing template 135 " \2 K) o \5 j: z* M
11.5 The Ranking Calculation 135 7 Y1 O G: ^/ U$ Q: S' `# J0 {5 [
11.6 Sectors and Options 136
- V+ c0 i) ~ \3 H, I y11.6.1 Direction sectors 136 / q b5 S+ j r
11.6.2 Overriding values from GH Windfarmer 136
3 `) U- U% r7 j. l11.7 Output folders and file naming convention 137
0 q: P _- f! q/ P. H11.8 Image viewer 138
3 J" M3 b; x" r: s0 `( uAPPENDIX A Communication Between Bladed And External Controllers 139
% b7 s& [# W8 H9 |A.1 Data exchange records 139
, |. U5 l6 U; P6 O6 `+ rA.2 Record 1: the Status flag 144 7 k# g% K* A/ R& C* U2 \
A.3 Sending messages to the simulation 145 : ?: `! X# f* [
A.4 Pitch and torque override 145 : ~4 f( C* q5 y
A.5 Sending logging output to Bladed 145 0 |$ h& y. Q- N
APPENDIX B Example External Controller Code In Selected Languages 147
+ e# k9 }8 M2 t' vB.1 Simple example of DLL code written in C 147
, @# X# |! m& QB.2 Simple example of DLL code written in FORTRAN 90 148
( ]% K9 G8 M/ C3 j' V- PB.3 Simple example of EXE code written in FORTRAN 90 149
! s; S1 ~ @; H! B vAPPENDIX C GEARBOX DLL INTERFACE SPECIFICATION 150
& z$ d8 P. Q: Z+ J$ N% Y4 jAPPENDIX D GENERATOR DLL INTERFACE SPECIFICATION 157
: f: D4 W" V" W/ _: V/ n% _REFERENCES |
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