Eddy-current and temperature of the sheath in three-phase pipe-sheathing systems

The vibration control of rotors is often performed using elastomeric or fluid dampers together with rolling element or hydrodynamic type bearings. Electromagnetic dampers seem a valid alternative to conventional solutions and also to active magnetic bearings (AMBs) because their simpler architecture, size and, if of transformer type, also for the absence of power electronics, position sensors, and any fast feedback loop. However, transformer eddy current dampers require a constant voltage power supply than can be provided by an embedded generator to reduce cost and improve the reliability. The present paper proposes a self-powered damper to fulfill these requirements. A three-phase permanent magnet electric generator (connected to the rotating shaft) generates the required power for the damping device. The generator is connected to the damping circuit by means of tuned impedance and a three-phase rectifier.

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Eddy currents in thin circular cylinders of uniform conductivity, due to periodically changing magnetic fields, in two dimensions

Mathematical Proceedings of the Cambridge Philosophical Society ◽

10.1017/s0305004100013761 ◽

1927 ◽

Vol 23 (8) ◽

pp. 901-906 ◽

Cited By ~ 13

Author(s):

F. W. Carter

Keyword(s):

Eddy Current ◽

Eddy Currents ◽

Two Dimensions ◽

Circular Cylinders ◽

Two Dimensional ◽

Total Field ◽

Current Field ◽

Conducting Material ◽

Eddy Current Losses ◽

Three Phase

The paper deals with the eddy currents in thin circular cylinders of uniform conducting material, due to periodic currents in conductors lying parallel to the axis of the cylinder, or to the rotation of the cylinder in a two-dimensional field of force. The first of these problems was discussed by Mr M. B. Field in a paper entitled “Eddy current losses in three-phase cable sheaths,” read before the British Association at their Cambridge meeting in 1904. The solution proposed, however, although probably sufficient for the object, is mathematically defective, in that the field due to the current carried by the cable is assumed as the total field, the effect of the eddy-current field on the eddy currents themselves being left out of account.

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Finite element computation of eddy current losses in nonlinear ferromagnetic sheaths of three-phase power cables

IEEE Transactions on Power Delivery ◽

10.1109/61.141814 ◽

1992 ◽

Vol 7 (3) ◽

pp. 1060-1067 ◽

Cited By ~ 18

Author(s):

D. Labridis ◽

P. Dokopoulos

Keyword(s):

Finite Element ◽

Eddy Current ◽

Power Cables ◽

Eddy Current Losses ◽

Three Phase ◽

Element Computation ◽

Finite Element Computation

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Analisa Stray Losses Pada Struktur Transformator Daya Satu Fasa 275 Kv 83.3 MVA

JTTM : Jurnal Terapan Teknik Mesin ◽

10.37373/msn.v1i1.13 ◽

2020 ◽

Vol 1 (1) ◽

pp. 32-40

Author(s):

Asep Saepudin Saepudin

Keyword(s):

Finite Element ◽

Eddy Current ◽

Simulation Study ◽

Single Phase ◽

3D Finite Element ◽

Eddy Current Losses ◽

Versus Measurement ◽

Three Phase

Background The jurnal discusse stray losses are generated by eddy current losses in the single phase transformer construction parts, such as Main tank, cover,core clamp and flitch plate. Stray losses can’t measurement direct and only calculated. Aim This study is to accurate calculated stray losses are generated in the single phase transformer construction parts in order to get more accurate calculated compared with measured and to know calculation versus measurement and versus simulation. Method This study using 3D Finite Element Metode with basis software ANSYS in the single phase transformer construction parts Result The stray losses in the single phase transformer construction parts, so that it hasn’t a simple stray losses divided by 3 compared to three phase transformers with same power and voltage. Conclusion Base on this study the total stray losses around 30%-37% from Load Losses and impove approxi-mately 9% compared between existing calculation and this simulation study versus measurement.

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