Detection of Ending Winding Wear Regulation Acting by Electromagnetic Force in Synchronous Generators under both SISC and SAGE Conditions

This paper studies the stator winding electromagnetic force behaviors before and after rotor inter-turn short circuit (RISC) in synchronous generator. Different from other studies, this paper not only studies the electromagnetic force characteristics, but also investigates the mechanical responses, the damage regularity, and the countermeasure of the stator winding. Firstly, formulas of electromagnetic force online and end part are obtained. Then, a 3D finite element model of a 3-pair-pole simulation generator is applied to get the electromagnetic force, and the dangerous stator slot is found. Finally, the mechanical response of each end winding is acquired, and especially the directional deformations of nose part are calculated. It shows that the occurrence of RISC will bring in times of rotor rotating frequency components to electromagnetic force, but the DC component and 2p times of rotor rotating frequency components are still the main that will be decreased. Additionally, the winding insulation wear in the same layer is more serious than that in a different layer, nose fatigue fracture begins with the center, and nose insulation wear starts from the top.

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Study on Adjustment Method of Output of Synchronous Generators for Transient Stability Improvement in Power System with Penetration of Renewable Energy Sources

IEEJ Transactions on Power and Energy ◽

10.1541/ieejpes.138.815 ◽

2018 ◽

Vol 138 (10) ◽

pp. 815-821

Author(s):

Shota Abe ◽

Daisuke Iioka ◽

Hiroumi Saitoh

Keyword(s):

Renewable Energy ◽

Power System ◽

Transient Stability ◽

Renewable Energy Sources ◽

Energy Sources ◽

Synchronous Generators ◽

Adjustment Method

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Study on the Modes of Operation of a Multi-Machine Installations with Mechanical Reduction

Alternative Energy and Ecology (ISJAEE) ◽

10.15518/isjaee.2019.10-12.012-022 ◽

2019 ◽

pp. 12-22

Author(s):

A. M. Oleynikov ◽

L. N. Kanov

Keyword(s):

Mathematical Description ◽

Reactive Power ◽

Maximum Efficiency ◽

Wind Flow ◽

System Of Equations ◽

Mechanical Equilibrium ◽

Synchronous Generators ◽

Electromagnetic Excitation ◽

Number Of Generators ◽

Wide Range

The paper gives the description of the original wind electrical installation with mechanical reduction in which the output of vertical axis wind turbine with rather low rotation speed over multiplicator is distributed to a certain number of generators. The number of acting generators is determined by the output of actual operating wind stream at each moment. According to this constructive scheme, it is possible to provide effective and with maximum efficiency installation work in a wide range of wind speeds and under any schedule issued to the consumer of electricity. As there are no any experience in using such complexes, mathematical description of its main elements is given, namely windwheels, generators with electromagnetic excitation of magnetic electrical type, then their interaction with windwheel, and also the results of mathematical modeling of work system regimes under using the offered system of equations. The basis for the mathematical description of the main elements of the installation – synchronous generators – are the system of equations of electrical and mechanical equilibrium in relative units in rotating coordinates without considering saturation of the magnetic circuit. The equation of mechanical equilibrium systems includes torque and brake windwheel electromagnetic moments of generators with taking into account the reduction coefficients and friction. In addition, we specify the alternator rotor dynamics resulting from continuous torque of windwheel fluctuations under the influence of unsteady wind flow and wind speed serving as the original variable is modeled by a set of sinusoids. Model simplification is achieved by equivalization of similar generators and by disregarding these transitions with a small time constant. Calculation the installation with synchronous generators of two types of small and medium capacity taking into account the operational factors allowed us to demonstrate the logic of interactions in the main elements of the reported complex in the process of converting wind flow into the generated active and reactive power. We have shown the possibility of stable system work under changeable wind stream condition by regulating of the plant blade angle and with simultaneous varying of generator number of different types. All these are in great interest for project organizations and power producers.

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Superconducting Wind Generators with Capacities of 10 MW and Larger

Elektrichestvo ◽

10.24160/0013-5380-2020-10-59-67 ◽

2020 ◽

Vol 10 (10) ◽

pp. 59-67

Author(s):

Victor N. ANTIPOV ◽

◽

Andrey D. GROZOV ◽

Anna V. IVANOVA ◽

◽

...

Keyword(s):

High Temperature ◽

Low Temperature ◽

Wind Power ◽

State Of The Art ◽

Superconducting Materials ◽

Commercial Application ◽

Synchronous Generators ◽

High Temperature Superconducting ◽

Wind Generators ◽

Main Factor

The overall dimensions and mass of wind power units with capacities larger than 10 MW can be improved and their cost can be decreased by developing and constructing superconducting synchronous generators. The article analyzes foreign conceptual designs of superconducting synchronous generators based on different principles: with the use of high- and low-temperature superconductivity, fully superconducting or only with a superconducting excitation system, and with the use of different materials (MgB2, Bi2223, YBCO). A high cost of superconducting materials is the main factor impeding commercial application of superconducting generators. In view of the state of the art in the technology for manufacturing superconductors and their cost, a conclusion is drawn, according to which a synchronous gearless superconducting wind generator with a capacity of 10 MW with the field winding made of a high-temperature superconducting material (MgB2, Bi-2223 or YBCO) with the «ferromagnetic stator — ferromagnetic rotor» topology, with the stator diameter equal to 7—9 m, and with the number of poles equal to 32—40 has prospects for its practical use in the nearest future.

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