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Showing 1 to 13 of 13 for “"Subsynchronous"”.
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Subsynchronous Resonance in Wind Farms
… series compensated transmission lines may cause subsynchronous resonance (SSR) in turbine-generators, which can lead to electrical instability at subsynchronous frequencies and potential turbine-generator shaft failures. This thesis deals primarily with the potential of subsynchronous resonance …
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Application of Bifurcation Theory to Subsynchronous Resonance in Power Systems
… As a result, the power system oscillates subsynchronously with a small limit-cycle attractor. As the compensation level increases, the limit cycle grows and then loses stability via a secondary Hopf bifurcation, resulting in the creation of a two-period quasiperiodic subsynchronous …
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Influence of Induced Unbalance on Subsynchronous Vibrations of an Automotive Turbocharger
… in most or all automotive turbochargers. High subsynchronous amplitudes can cause a variety of problems in areas such as mechanical failures, emissions regulations and rotor design. Self-excited vibrations from sources of damping can lock in at lateral natural frequencies causing dangerously …
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Subsynchronous resonance in series compensated networks with high penetration of renewable energy sources
… RES through series compensated lines results in subsynchronous resonance (SSR) between generator rotors and the grid. SSR is a phenomenon where there is exchange of electrical energy between the generator shaft system and the transmission system below the fundamental power frequency leading to …
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Frequency Scan–Based Mitigation Approach of Subsynchronous Control Interaction in Type-3 Wind Turbines
Subsynchronous oscillations (SSO) were an issue that occurred in the past with conventional generators and were studied extensively throughout the years. However, with the rise of inverter-based resources, a new form of SSO emerged under the name subsynchronous control interaction (SSCI). More …
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Evaluation of the Effectiveness of an Active Magnetic Damper (AMD) in Damping Subsynchronous Vibrations in a Flexible Rotor
Subsynchronous vibrations such as those caused by rotor instability represent one of the most harrowing scenarios of rotor vibration. They are related to a great diversity of destabilizing forces and some of them are not well understood yet. Therefore, special attention must be paid to this type of …
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A Study of Methods for Improving the Dynamic Stability of High-Speed Turbochargers
… The high-speed turbocharger is known to have subsynchronous vibrations at high amplitudes for a wide speed range that could reach 150,000 rpm. The bearing fluid-film whirl instability is the main source of the subsynchronous vibration. The nonlinear reaction forces inside the bearings are …
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Novel PV Solar Farm Control as STATCOM (PV-STATCOM) for SSR Mitigation in Synchronous Generators and Wind Farms
… series compensation can potentially cause subsynchronous resonance (SSR) which can lead to significant damage in shafts of synchronous generators and wind farms. Dynamic reactive power compensators such as STATCOM and SVCs are typically used for mitigation of SSR, but these are quite …
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Distance Protection Aspects of Transmission Lines Equipped with Series Compensation Capacitors
… This is done by analyzing the synchronous and subsynchronous content of the V and I signals seperately which provides adequate information to compute the series L and C of the line.
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Dynamic Performance of Turbocharger Rotor-Bearing Systems
… motion whereas the FRBT was dominated by subsynchronous motion throughout the entire range of speeds. The TTR was also used to compare frictional losses within the bearings. A study of run-down times after the pressurized air supply was removed indicated that the BBT has significantly …
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Adaptive digital distance protection for series compensated transmission lines
… order to minimise the detrimental effect of the subsynchronous oscillation on the relay decision logic. Finally, the relay is thoroughly tested for many different system configurations, to fully evaluate the relay response.
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Influence of higher time harmonics on the electrical and mechanical performance of an inverter-fed squirrel cage induction motor
… under synchronous characteristic Vᵣ/50 and subsynchronous characteristic Vᵣ/87. The respective voltage and current frequency spectrums of the excitation source are analyzed and the harmonic content determined. Performance executed under identical operating respectively and results are …
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Measured and Predicted Rotor-Pad Transfer Functions for a Rocker-Pivot Tilting-Pad Journal Bearing
… at the frequency of the unstable eigenvalue (subsynchronously reduced) predicted a destabilizing cross-coupled stiffness coefficient at the onset of instability within 1% of the full model, while synchronously reduced coefficients for the lightly loaded bearing required 25% more destabilizing …