The mechanical effects of short-circuit currents in - Montefiore

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a) b) c) 1,5 m 1,0 0,5 0,0 δ 1 Movement of the main conductor Force in the main conductor δ k δ m ,b c0 b c -0,5 δ -1,0 -2,0 -1,5 -1,0 -0,5 0,0 0,5 1,0 1,5 m 2,0 1,5 m 1,0 0,5 0,0 -0,5 δ 1 δ k δ -1,0 -2,0 -1,5 -1,0 -0,5 0,0 0,5 1,0 1,5 m 2,0 1,5 m 1,0 0,5 0,0 -0,5 δ max δ max δ k δ 1 b c δ δ m δ m b c0 bc0 bc b ct b ct l dmax -1,0 -2,0 -1,5 -1,0 -0,5 0,0 0,5 1,0 1,5 m 2,0 b ct Figure 3.34 Movement of the main conductor and forces in the main conductor; case 4 [Ref 43, Ref 44] Ik = 28,3 kA; tk = 0,3 s a) without dropper: current path A b) with dropper: current path B; dropper length 6,045m c) with dropper: current path C; dropper length 6,045m l dmax 48
a) b) c) 3 m 2 1 0 -1 δ m δ 1 Movement of the main conductor Force in the main conductor δ k δ bc0 bc -2 -4 -3 -2 -1 0 1 2 3 m 4 3 m 2 1 0 -1 δ1 δmax δ m bc0 b c δ k δ -2 -4 -3 -2 -1 0 1 2 3 m 4 Figure 3.35 Movement of the main conductor and forces in the main conductor [Ref 39] Ik = 30 kA ; tk = 0,3 s a) without dropper : current path A b) and c) with dropper: current path B; dropper lengths 8,1 m and 9,1 m b ct l dmax To estimate δmax according to equation (3.3) it is necessary to calculate the dynamic sag bct of the span without dropper. This needs the knowledge of the shortcircuit tensile force Ft without dropper. Therefore the calculation is done with equations [(*20)] - [(*34)] and equations [(*36)] - [(*39)] and it becomes bct = CF CD bc. The swing-out angle at which the short-circuit tensile force Ft occurs in a span with dropper depends on the actual maximum swing-out angle δmax. If δmax > δ1, the swingout of the span is not influenced by the dropper during Tres/4; Ft is reached unless the dropper stretches and the calculation is equal to a span without dropper. In the other case if δmax < δ1, the swingout is influenced by the dropper during Tres/4 and Ft has its maximum at b ct 49 30 kN 20 10 0 30 kN 20 10 0 0,3 1 2 3 s 4 0 0 0,3 1 2 3 s 4 30 kN 20 10 0 0 0,3 1 2 3 s 4 δk for δmax > δk otherwise at δmax for δmax < δk. Therefore it has to be distinguished between the following cases when calculating the load parameter ϕ: – δmax ≥ δ1: The load parameter ϕ is obtained as for a span without dropper according to equation [(*32)] (3.4) ⎧ ⎛ 2 ⎪ 3 ⎞ ⎜ 1 + r −1⎟ ϕ = ⎝ ⎠ ⎨ ⎪3( r sin δk + cos δk ⎩ −1 ) for for Tk1 ≥ T Tk1 < T – δmax < δ1: The load parameter ϕ is obtained as follows: res res / 4 / 4
Page 1 and 2: THE MECHANICAL EFFECTS OF SHORT-CIR
Page 3 and 4: 3.7. Special problems .............
Page 5 and 6: 1. INTRODUCTION 1.1. GENERAL PRESEN
Page 7 and 8: The pinch (first maximum) can be ve
Page 9 and 10: 1.3.3.2 Supporting structures Simil
Page 11 and 12: This method allows to state the sho
Page 13 and 14: and becomes the static force in equ
Page 15 and 16: (2.26) M el-pl ⎡ y d/ 2 y = 2⎢
Page 17 and 18: V σ 3 2,5 2 1,5 1 mechanical reson
Page 19 and 20: V F 3 2,5 2 1,5 1 mechanical resona
Page 21 and 22: 1. eigenmode 2. eigenmode 3. eigenm
Page 23 and 24: (2.43) U E max max = 1 2 1 = 2 l
Page 25 and 26: m (2.47) M = σm = Z mσ m dm 2 J w
Page 27 and 28: profiles in Figure 2.14 it follows
Page 29 and 30: (2.71) 2 tube tube 4 tube U ∂U
Page 31 and 32: 2.3.2. Influence of two busbars a)
Page 33 and 34: Asymmetrical associated-phase layou
Page 35 and 36: d)Methods used IEC 60865 method : -
Page 37 and 38: Section 3.4 deals with the effects
Page 39 and 40: In Figure 3.5 to Figure 3.8, the ma
Page 41 and 42: Figure 3.17 Comparison calculated a
Page 43 and 44: movement of the dropper (swing out
Page 45 and 46: This value has to be compared with
Page 47: EN 60865-1 [Ref 3] with the assumpt
Page 51 and 52: Droppers with fixed upper ends Duri
Page 53 and 54: Manuzio developed a simplified meth
Page 55 and 56: From prior tests the stiffness valu
Page 57 and 58: Force / kN Force / kN 100mm 200mm 4
Page 59 and 60: 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 ESL F
Page 61 and 62: 3.7. SPECIAL PROBLEMS 3.7.1. Auto-r
Page 63 and 64: for the maximum outswing and the ma
Page 65 and 66: Zug-/Druck-Kraft in kN Z eit in s F
Page 67 and 68: The numerical resolution of these e
Page 69 and 70: 4. GUIDELINES FOR DESIGN AND UPRATI
Page 71 and 72: standards and tested under specifie
Page 73 and 74: 5. PROBABILISTIC APPROACH TO SHORT-
Page 75: f G f(L) Lt Ls 75 G(L) ∞ R = ∫
Page 78 and 79: Only the lowest break values are im
Page 80 and 81: 5.2.2. A global Approach For analyz
Page 82 and 83: to multinode operation can compared
Page 84 and 85: 5.2.3.1.7. Proposed Approach The st
Page 86 and 87: The first case (Figure 5.14) corres
Page 88 and 89: centers are normally balanced by ba
Page 90 and 91: Remark: The risk integral (5.3) can
Page 92 and 93: 1,0 0,8 0,6 0,4 0,2 0,0 -0,2 -0,4 -
Page 94 and 95: The histograms below for the instan
Page 96 and 97: 5.2.3.8.2. Reliability based design
Page 98 and 99:
power converter in a three phase br
Page 100 and 101:
The time functions of the currents
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a) Determination of the linear mome
Page 104 and 105:
Figure 6.11 Coefficients mJs1 and m
Page 106 and 107:
7. REFERENCES Ref 1. IEC TC 73/CIGR
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Ref 42. Stein, N.; Miri, A.M.; Meye
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Ref 80. Fiabilité des structures d
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8. ANNEX 8.1. THE EQUIVALENT STATIC
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Figure 8.2 What is ESL in this case
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As the eigenfrequency of the portal
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Figure 8.9 Case 3 (third eigenfrequ
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Both cases have the same 200-kV-arr
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a) c) 5 +25 % 0 % 4 3 F c / F st 2
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a) b) 24 kN 20 +25 % 0 % 2,0 m F c
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Case *11 (EDF 1990) This is the 102
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8.4. INFLUENCE OF THE RECLOSURE The
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( ( δ ) ( δ ) ) T = Mg08 . b r .
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IEC 60865 Calculations If the clear
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8.6.1.1 With calculation of the rel
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f) Calculation of the stresses due
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d) Determination of the forces at t
Page 140 and 141:
8.7. ERRATA TO BROCHURE NO 105 In V
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