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Richard M Murray - One of the best experts on this subject based on the ideXlab platform.
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Bifurcation control of Rotating Stall with actuator magnitude and rate limits: Part I-model reduction and qualitative dynamics
Automatica, 2002Co-Authors: Yong Wang, Richard M MurrayAbstract:Nonlinear qualitative analysis is performed on the Moore-Greitzer model to unfold a geometric picture of the effects of actuator magnitude saturation, bandwidth, and rate limits on active control of Rotating Stall in axial compressors with bleed valves.
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bleed valve rate requirements evaluation in Rotating Stall control on axial compressors
Journal of Propulsion and Power, 2000Co-Authors: S. Yeung, Yong Wang, Richard M MurrayAbstract:The actuator rate requirements are evaluated for control of Rotating Stall using a bleed valve and to provide tools for predicting these requirements. Modie cation of both the stable and unstable parts of the compressor characteristic via addition of continuous air injection serves to reducetherequirement of a bleed valve used forthe purpose of Rotating Stall stabilization. Analytical tools based on low-order models (2‐3 states)and simulation tools based on a reduced-ordermodel (37states)aredescribed. Ableedactuatorratelimitstudy ispresentedto compare the actuator requirements predicted by theory, simulation, and experiment using a single-stage, low-speed, axial compressor.Thecomparisonsshowthatthepredictionsobtainedfrom theory andsimulationssharethesametrend as the experiments, with increasing accuracy as the complexity of the underlying model increases. Some insights on the design of bleed ‐compressor pair are given.
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Evaluation of Bleed Valve Rate Requirements in Nonlinear Control of Rotating Stall on Axial Flow Compressors
1998Co-Authors: S. Yeung, Yong Wang, Richard M MurrayAbstract:In this paper we evaluate the actuator rate requirements for control of Rotating Stall using a bleed valve and provide tools for predicting these requirements. Modification of both the stable and unstable parts of the compressor characteristic via addition of continuous air injection serves to reduce the requirement of a bleed valve used for the purpose of Rotating Stall stabilization. Analytical tools based on low order models (2-3 states) and simulation tools based on a reduced order model (37 states) are described. A bleed actuator rate limit study is presented to compare the actuator requirements predicted by theory, simulation, and experiment. The comparisons show that the predictions obtained from theory and simulations share the same trend as the experiments, with increasing accuracy as the complexity of the underlying model increases. Some insights on the design of a bleed-compressor pair are given.
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reduction of bleed valve rate requirements for control of Rotating Stall using continuous air injection
International Conference on Control Applications, 1997Co-Authors: S. Yeung, Richard M MurrayAbstract:Actuation of the compressor characteristic, via the use of continuous air injection, has been experimentally verified on a single-stage, low-speed axial compressor, to provide a method of reducing the rate requirement of bleed valve control of Rotating Stall. The experiments show that the bleed valve rate requirement is reduced from approximately 145 Hz to below 10 Hz when the amount of compressor characteristic actuation is increased. Theoretical tools based on a low order model (1-3 states) and simulations based on a reduced order distributed model (37 states) have been developed to estimate the gain and rate requirements of the bleed controller. All of the analytical formulas and simulations share the same qualitative trends with respect to the experiments. This qualitative agreement indicates that bleed valve control of Rotating Stall depends crucially on the rate limit of the bleed valve, and the theoretical tools indicate that the rate limit requirement depends on both the stable and the unstable part of the compressor characteristic. By combining compressor characteristic identification tools and the analytic relations, insights for designing a compressor-bleed pair are provided.
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Rotating Stall control of an axial flow compressor using pulsed air injection
Journal of Turbomachinery-transactions of The Asme, 1997Co-Authors: R Dandrea, Robert L Behnken, Richard M MurrayAbstract:This paper presents the use of pulsed air injection to control Rotating Stall in a low-speed, axial flow compressor. In the first part of the paper, the injection of air is modeled as an unsteady shift of the compressor characteristic, and incorporated into a low dimensional model of the compressor. By observing the change in the bifurcation behavior of this model subject to nonlinear feedback, the viability of various air injection orientations is established. An orientation consistent with this analysis is then used for feedback control. By measuring the unsteady pressures near the rotor face, a control algorithm determines the magnitude and phase of the first mode of Rotating Stall and controls the injection of air in the front of the rotor face. Experimental results show that this technique eliminates the hysteresis loop normally associated with Rotating Stall. A parametric study is used to determine the optimal control parameters for suppression of Stall. The resulting control strategy is also shown to suppress surge when a plenum is present. Using a high-fidelity model, the main features of the experimental results are duplicated via simulations.
Siva S. Banda - One of the best experts on this subject based on the ideXlab platform.
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Brief Rotating Stall control for axial flow compressors
Automatica, 2001Co-Authors: Calin Belta, Andrew G. Sparks, Siva S. BandaAbstract:Rotating Stall is a primary constraint for the performance of axial flow compressors. This paper establishes a necessary and sufficient condition for a feedback controller to locally stabilize the critical equilibrium of the uniform flow at the inception of Rotating Stall. The explicit condition obtained in this paper provides an effective synthesis tool for Rotating Stall control.
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an overview of Rotating Stall and surge control for axial flow compressors
IEEE Transactions on Control Systems and Technology, 1999Co-Authors: Andrew G. Sparks, Siva S. BandaAbstract:Modeling and control for axial flow compression systems have received great attention in recent years. The objectives are to suppress Rotating Stall and surge, to extend the stable operating range of the compressor system, and to enlarge domains of attraction of stable equilibria using feedback control methods. The success of this research field will significantly improve compressor performance and thus future aeroengine performance. This paper surveys the research literature and summarizes the major developments in this active research field, focusing on the modeling and control perspectives to Rotating Stall and surge for axial flow compressors.
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Bifurcation based nonlinear feedback control for Rotating Stall in axial flow compressors
International Journal of Control, 1997Co-Authors: Andrew G. Sparks, Siva S. BandaAbstract:Classical bifurcation analysis for nonlinear dynamics is used to derive a nonlinear feedback control law that eliminates the hysteresis loop associated with Rotating Stall, and extends the stable operating range in axial flow compressors. The proposed control system employs pressure rise as output measurement and throttle position as the actuating signal for which both sensor and actuator exist in the current configuration of axial flow compressors. Thus, our results provide a practical solution to Rotating Stall control for axial flow compressors.
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Bifurcation based nonlinear feedback control for Rotating Stall in axial flow compressors
Proceedings of the 1997 American Control Conference (Cat. No.97CH36041), 1997Co-Authors: Andrew G. Sparks, Siva S. BandaAbstract:Classical bifurcation analysis for nonlinear dynamics is used to derive a nonlinear feedback control law that eliminates the hysteresis loop associated with Rotating Stall and extends the stable operating range in axial flow compressors. The proposed control system employs pressure rise as output measurement and throttle position as actuating signal for which both sensor and actuator exist in the current configuration of axial flow compressors. Thus, our results provide a practical solution for Rotating Stall control in axial flow compressors.
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Rotating Stall control for axial flow compressors
Proceedings of the 37th IEEE Conference on Decision and Control (Cat. No.98CH36171), 1Co-Authors: Calin Belta, Andrew G. Sparks, Siva S. BandaAbstract:Rotating Stall is a primary constraint for the performance of axial flow compressors. This paper establishes a necessary and sufficient condition for a quadratic feedback controller to locally stabilize the critical equilibrium of the uniform flow at the inception of Rotating Stall. The explicit condition obtained in this paper provides an effective synthesis tool for Rotating Stall control.
Andrew G. Sparks - One of the best experts on this subject based on the ideXlab platform.
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Brief Rotating Stall control for axial flow compressors
Automatica, 2001Co-Authors: Calin Belta, Andrew G. Sparks, Siva S. BandaAbstract:Rotating Stall is a primary constraint for the performance of axial flow compressors. This paper establishes a necessary and sufficient condition for a feedback controller to locally stabilize the critical equilibrium of the uniform flow at the inception of Rotating Stall. The explicit condition obtained in this paper provides an effective synthesis tool for Rotating Stall control.
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an overview of Rotating Stall and surge control for axial flow compressors
IEEE Transactions on Control Systems and Technology, 1999Co-Authors: Andrew G. Sparks, Siva S. BandaAbstract:Modeling and control for axial flow compression systems have received great attention in recent years. The objectives are to suppress Rotating Stall and surge, to extend the stable operating range of the compressor system, and to enlarge domains of attraction of stable equilibria using feedback control methods. The success of this research field will significantly improve compressor performance and thus future aeroengine performance. This paper surveys the research literature and summarizes the major developments in this active research field, focusing on the modeling and control perspectives to Rotating Stall and surge for axial flow compressors.
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Bifurcation based nonlinear feedback control for Rotating Stall in axial flow compressors
International Journal of Control, 1997Co-Authors: Andrew G. Sparks, Siva S. BandaAbstract:Classical bifurcation analysis for nonlinear dynamics is used to derive a nonlinear feedback control law that eliminates the hysteresis loop associated with Rotating Stall, and extends the stable operating range in axial flow compressors. The proposed control system employs pressure rise as output measurement and throttle position as the actuating signal for which both sensor and actuator exist in the current configuration of axial flow compressors. Thus, our results provide a practical solution to Rotating Stall control for axial flow compressors.
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Bifurcation based nonlinear feedback control for Rotating Stall in axial flow compressors
Proceedings of the 1997 American Control Conference (Cat. No.97CH36041), 1997Co-Authors: Andrew G. Sparks, Siva S. BandaAbstract:Classical bifurcation analysis for nonlinear dynamics is used to derive a nonlinear feedback control law that eliminates the hysteresis loop associated with Rotating Stall and extends the stable operating range in axial flow compressors. The proposed control system employs pressure rise as output measurement and throttle position as actuating signal for which both sensor and actuator exist in the current configuration of axial flow compressors. Thus, our results provide a practical solution for Rotating Stall control in axial flow compressors.
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Rotating Stall control for axial flow compressors
Proceedings of the 37th IEEE Conference on Decision and Control (Cat. No.98CH36171), 1Co-Authors: Calin Belta, Andrew G. Sparks, Siva S. BandaAbstract:Rotating Stall is a primary constraint for the performance of axial flow compressors. This paper establishes a necessary and sufficient condition for a quadratic feedback controller to locally stabilize the critical equilibrium of the uniform flow at the inception of Rotating Stall. The explicit condition obtained in this paper provides an effective synthesis tool for Rotating Stall control.
Edward M. Greitzer - One of the best experts on this subject based on the ideXlab platform.
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Role of Blade Passage Flow Structurs in Axial Compressor Rotating Stall Inception
Journal of Turbomachinery, 1999Co-Authors: D. A. Hoying, Huu Duc Vo, C. S. Tan, Edward M. GreitzerAbstract:The influence of three-dimensional flow structures within a compressor blade passage has been examined computationally to determine their role in Rotating Stall inception. The computations displayed a short length-scale (or spike) type of Stall inception similar to that seen in experiments; to the authors' knowledge this is the first time such a feature has been simulated. A central feature observed during the Rotating Stall inception was the tip clearance vortex moving forward of the blade row leading edge. Vortex kinematic arguments are used to provide a physical explanation of this motion as well as to motivate the conditions for its occurrence. The resulting criterion for this type of Stall inception (the movement of the tip clearance vortex forward of the leading edge) depends upon local flow phenomena related to the tip clearance with the implication that for this and possibly other Stall mechanisms the flow structure within the blade passages must be addressed to explain the stability of an axial compression system that exhibits such short length-scale disturbances.
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role of blade passage flow structures in axial compressor Rotating Stall inception
ASME 1998 International Gas Turbine and Aeroengine Congress and Exhibition, 1998Co-Authors: D. A. Hoying, C. S. Tan, Edward M. GreitzerAbstract:The influence of three-dimensional flow structures within a compressor blade passage has been examined computationally to determine their role in Rotating Stall inception. The computations displayed a short length-scale (or spike) type of Stall inception similar to that seen in experiments; to the authors’ knowledge this is the first time such a feature has been simulated. A central feature observed during the Rotating Stall inception was the tip clearance vortex moving forward of the blade row leading edge. Vortex kinematic arguments are used to provide a physical explanation of this motion as well as to motivate the conditions for its occurrence. The resulting criterion for this type of Stall inception (which appears generic for axial compressors with tip-critical flow fields) depends upon local flow phenomena related to the tip clearance and it is thus concluded that the flow structure within the blade passages must be addressed to explain the stability of an axial compression system which exhibits such short length-scale disturbances.© 1998 ASME
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modeling for control of Rotating Stall
Automatica, 1994Co-Authors: James D Paduano, Edward M. Greitzer, Lena Valavani, A H Epstein, G R GuenetteAbstract:Abstract An analytical model for control of Rotating Stall has been obtained from the basic fluid equations describing the process at inception. The model describes Rotating Stall as a traveling wave packet, sensed—in spatial components—via the Fourier decomposition of measurements obtained from a circumferential array of evenly distributed sensors (hot wires) upstream of the compressor. A set of “wiggly” inlet guide vanes (IGVs) equally spaced around the compressor annulus constitute the “forced” part of the model. Control is effected by launching waves at appropriate magnitude and phase, synthesized by spatial Fourier synthesis from individual IGV deflections. The effect of the IGV motion on the unsteady fluid process was quantified via identification experiments carried out on a low speed, single-stage axial research compressor. These experiments served to validate the theoretical model and refine key parameters in it. Further validation of the model was provided by the successful implementation of a complex-valued proportional control law, using a combination of first and second harmonic feedback; this resulted in an 18% reduction of Stalling mass flow, at essentially the same pressure rise.
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dynamic control of Rotating Stall in axial flow compressors using aeromechanical feedback
ASME 1994 International Gas Turbine and Aeroengine Congress and Exposition, 1994Co-Authors: D L Gysling, Edward M. GreitzerAbstract:Dynamic control of Rotating Stall in an axial flow compressor has been implemented using aeromechanical feedback. The control strategy developed used an array of wall jets, upstream of a single-stage compressor, which were regulated by locally reacting reed valves. These reed valves responded to flowfield pressure perturbations associated with the small amplitude perturbations that precede Rotating Stall. The valve design was such that the combined system, compressor plus reed valve controller, was stable under operating conditions that had been unstable without feedback. A 10% decrease in the Stalling flow coefficient was achieved using the control strategy, and the stable flow range was extended with no noticeable change in the steady state performance of the compression system.The experimental demonstration is the first use of aeromechanical feedback to extend the stable operating range of an axial flow compressor. It is also the first use of local feedback and dynamic compensation techniques to suppress Rotating Stall.The design of the experiment was based on a two-dimensional Stall inception model which incorporated the effect of the aeromechanical feedback. The physical mechanism for Rotating Stall in axial flow compressors was examined with focus on the role of dynamic feedback in stabilizing compression system instability. The effectiveness of the aeromechanical control strategy was predicted, and experimentally demonstrated, to depend on a set of non-dimensional control parameters that determine the interaction of the control strategy and the Rotating Stall dynamics.Copyright © 1994 by ASME
Zoltán S. Spakovszky - One of the best experts on this subject based on the ideXlab platform.
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Backward Traveling Rotating Stall Waves in Centrifugal Compressors
Journal of Turbomachinery, 2004Co-Authors: Zoltán S. SpakovszkyAbstract:Rotating Stall waves that travel against the direction of rotor rotation are reported for the first time and a new, low-order analytical approach to model centrifugal compressor stability is introduced. The model is capable of dealing with unsteady radially swirling flows and the dynamic effects of impeller-diffuser component interaction as it occurs in centrifugal compression systems. A simple coupling criterion is developed from first prin- ciples to explain the interaction mechanism important for system stability. The model findings together with experimental data explain the mechanism for first-ever observed backward traveling Rotating Stall in centrifugal compressors with vaned diffusers. Based on the low-order model predictions, an air injection scheme between the impeller and the vaned diffuser is designed for the NASA Glenn CC3 high-speed centrifugal compressor. The steady air injection experiments show an increase of 25% in surge-margin with an injection mass flow of 0.5% of the compressor mass flow. In addition, it is experimentally demonstrated that this injection scheme is robust to impeller tip-clearance effects and that a reduced number of injectors can be applied for similar gains in surge-margin. The results presented in this paper firmly establish the connection between the experimentally observed dynamic phenomena in the NASA CC3 centrifugal compressor and a first prin- ciples based coupling criterion. In addition, guidelines are given for the design of cen- trifugal compressors with enhanced stability.
