A model-assistant extended state observer(MESO)-based decoupling control strategy is proposed for boiler-turbine units in the presence of unknown external disturbance and model-plant mismatch. For ease of implementati...A model-assistant extended state observer(MESO)-based decoupling control strategy is proposed for boiler-turbine units in the presence of unknown external disturbance and model-plant mismatch. For ease of implementation, the decoupling compensator is reduced to the proportion integration(PI) decoupler with the frequency domain analysis, where the decoupling error in collusion of uncertainties and disturbances can be estimated by the proposed MESO and then compensated. To decrease the sensitivity of the dynamic error for the decoupling control and fulfill various requirements of constraints, such as safety operation, energy conservation, emission reduction, etc., the plant is transmitted through a scheduled steady state region which is achieved from the optimized reference governor in advance. Simulation results show that the proposed control strategy can well suppress various disturbances including a decoupling error, and multi-objective optimization can meet multiple requirements with the premise of safety production.展开更多
As the geometry of the volute of turbocharger compressor is non-axisymmetric,it causes a distortion at the outlet of the diffuser and influences the upstream components.A distortion model in which a pressure distortio...As the geometry of the volute of turbocharger compressor is non-axisymmetric,it causes a distortion at the outlet of the diffuser and influences the upstream components.A distortion model in which a pressure distortion was applied as outlet boundary condition was established to simulate the distortion induced by the volute.It turned out to be sufficient to impose a circumferentially asymmetric pressure distribution at the outlet of the diffuser to replace the volute.Based on the distortion model which was verified,the influence of the amplitude of the distortion on the performance of centrifugal compressor was studied in detail.The results show that the distortion severely harms aerodynamic stability of the investigated compressor.The larger the amplitude of the distortion,the worse the performance of the compressor.The distortion induced by asymmetric volute propagates to upstream components and causes local flow separation at part of diffuser and impeller,and then causes the compressor surge.When the amplitude of the volute distortion is 10%,the stable flow range of the centrifugal compressor decreases to near zero.To authors’knowledge,the relationship between the compressor performance and distortion amplitude is first obtained quantitatively,which provides evidence to improve the performance of turbocharger compressor by decreasing the distortion induced by asymmetric volute.展开更多
基金The National Natural Science Foundation of China(No.51576041,51506029)
文摘A model-assistant extended state observer(MESO)-based decoupling control strategy is proposed for boiler-turbine units in the presence of unknown external disturbance and model-plant mismatch. For ease of implementation, the decoupling compensator is reduced to the proportion integration(PI) decoupler with the frequency domain analysis, where the decoupling error in collusion of uncertainties and disturbances can be estimated by the proposed MESO and then compensated. To decrease the sensitivity of the dynamic error for the decoupling control and fulfill various requirements of constraints, such as safety operation, energy conservation, emission reduction, etc., the plant is transmitted through a scheduled steady state region which is achieved from the optimized reference governor in advance. Simulation results show that the proposed control strategy can well suppress various disturbances including a decoupling error, and multi-objective optimization can meet multiple requirements with the premise of safety production.
基金supported by the National Natural Science Foundation of China(Grant No.51176087)
文摘As the geometry of the volute of turbocharger compressor is non-axisymmetric,it causes a distortion at the outlet of the diffuser and influences the upstream components.A distortion model in which a pressure distortion was applied as outlet boundary condition was established to simulate the distortion induced by the volute.It turned out to be sufficient to impose a circumferentially asymmetric pressure distribution at the outlet of the diffuser to replace the volute.Based on the distortion model which was verified,the influence of the amplitude of the distortion on the performance of centrifugal compressor was studied in detail.The results show that the distortion severely harms aerodynamic stability of the investigated compressor.The larger the amplitude of the distortion,the worse the performance of the compressor.The distortion induced by asymmetric volute propagates to upstream components and causes local flow separation at part of diffuser and impeller,and then causes the compressor surge.When the amplitude of the volute distortion is 10%,the stable flow range of the centrifugal compressor decreases to near zero.To authors’knowledge,the relationship between the compressor performance and distortion amplitude is first obtained quantitatively,which provides evidence to improve the performance of turbocharger compressor by decreasing the distortion induced by asymmetric volute.
