Permanent magnet synchronous motor(PMSM)speed control systems with conventional linear active disturbance rejection control(CLADRC)strategy encounter issues regarding the coupling between dynamic response and disturba...Permanent magnet synchronous motor(PMSM)speed control systems with conventional linear active disturbance rejection control(CLADRC)strategy encounter issues regarding the coupling between dynamic response and disturbance suppression and have poor performance in suppressing complex nonlinear disturbances.In order to address these issues,this paper proposes an improved two-degree-of-freedom LADRC(TDOF-LADRC)strategy,which can enhance the disturbance rejection performance of the system while decoupling entirely the system's dynamic and anti-disturbance performance to boost the system robustness and simplify controller parameter tuning.PMSM models that consider total disturbances are developed to design the TDOF-LADRC speed controller accurately.Moreover,to evaluate the control performance of the TDOF-LADRC strategy,its stability is proven,and the influence of each controller parameter on the system control performance is analyzed.Based on it,a comparison is made between the disturbance observation ability and anti-disturbance performance of TDOF-LADRC and CLADRC to prove the superiority of TDOF-LADRC in rejecting disturbances.Finally,experiments are performed on a 750 W PMSM experimental platform,and the results demonstrate that the proposed TDOF-LADRC exhibits the properties of two degrees of freedom and improves the disturbance rejection performance of the PMSM system.展开更多
OBJECTIVE To explore the hypolipidemic mechanisms of the total phenylpropanoid glycosides fromLigustrum robustum(Roxb.) Blume(LRTPG) in hamsters using proteomics technique.METHODS The hamsters were fed with a high fat...OBJECTIVE To explore the hypolipidemic mechanisms of the total phenylpropanoid glycosides fromLigustrum robustum(Roxb.) Blume(LRTPG) in hamsters using proteomics technique.METHODS The hamsters were fed with a high fat diet to induce hyperlipidemia.Then LRTPG of high(1.2 g·kg^(-1)),medium(0.6 g·kg^(-1)) and low(0.3 g·kg^(-1)) doses were administrated daily for 4 weeks.Then the concentrations of plasma and hepatic lipids were determined using enzymic methods.The total protein was extracted from livers of the model group and the group treated with the high dose of LRTPG for label-free quantitative proteomics.RESULTS LRTPG significantly reduced the concentrations of plasma and hepatic lipids in hamsters fed a high fat diet.The proteomics data showed that a total of 2231 proteins were identified,and 549 proteins were found to be differentially expressed between the model group and the group treated with LRTPG.Among the 549 proteins,93 proteins were up-regulated and 59 proteins were down-regulated,and 397 proteins were absent or not.And some of these proteins were much related to the lipid metabolism.Further,gene ontology(GO) analysis indicated metabolic process,transport,oxidation-reduction process,phosphorylation,signal transduction,lipid metabolic process were the main biological processes that those differentially expressed proteins participated.KEGG pathway analysis showed that those proteins were involved in several metabolic pathways including oxidative phosphorylation,non-alcoholic fatty liver disease(NAFLD),PI3K-Akt signaling pathway,cAMP signaling pathway,cGMP-PKG signaling pathway.CONCLUSION The proteomics study could provide valuable clues to help us to understand the hypolipidemic mechanisms of LRTPG much better.展开更多
文摘Permanent magnet synchronous motor(PMSM)speed control systems with conventional linear active disturbance rejection control(CLADRC)strategy encounter issues regarding the coupling between dynamic response and disturbance suppression and have poor performance in suppressing complex nonlinear disturbances.In order to address these issues,this paper proposes an improved two-degree-of-freedom LADRC(TDOF-LADRC)strategy,which can enhance the disturbance rejection performance of the system while decoupling entirely the system's dynamic and anti-disturbance performance to boost the system robustness and simplify controller parameter tuning.PMSM models that consider total disturbances are developed to design the TDOF-LADRC speed controller accurately.Moreover,to evaluate the control performance of the TDOF-LADRC strategy,its stability is proven,and the influence of each controller parameter on the system control performance is analyzed.Based on it,a comparison is made between the disturbance observation ability and anti-disturbance performance of TDOF-LADRC and CLADRC to prove the superiority of TDOF-LADRC in rejecting disturbances.Finally,experiments are performed on a 750 W PMSM experimental platform,and the results demonstrate that the proposed TDOF-LADRC exhibits the properties of two degrees of freedom and improves the disturbance rejection performance of the PMSM system.
基金supported by the PUMC(Peking Union Medical College)Youth Fund(3332015142) National Natural Science Foundation of China(81703746)
文摘OBJECTIVE To explore the hypolipidemic mechanisms of the total phenylpropanoid glycosides fromLigustrum robustum(Roxb.) Blume(LRTPG) in hamsters using proteomics technique.METHODS The hamsters were fed with a high fat diet to induce hyperlipidemia.Then LRTPG of high(1.2 g·kg^(-1)),medium(0.6 g·kg^(-1)) and low(0.3 g·kg^(-1)) doses were administrated daily for 4 weeks.Then the concentrations of plasma and hepatic lipids were determined using enzymic methods.The total protein was extracted from livers of the model group and the group treated with the high dose of LRTPG for label-free quantitative proteomics.RESULTS LRTPG significantly reduced the concentrations of plasma and hepatic lipids in hamsters fed a high fat diet.The proteomics data showed that a total of 2231 proteins were identified,and 549 proteins were found to be differentially expressed between the model group and the group treated with LRTPG.Among the 549 proteins,93 proteins were up-regulated and 59 proteins were down-regulated,and 397 proteins were absent or not.And some of these proteins were much related to the lipid metabolism.Further,gene ontology(GO) analysis indicated metabolic process,transport,oxidation-reduction process,phosphorylation,signal transduction,lipid metabolic process were the main biological processes that those differentially expressed proteins participated.KEGG pathway analysis showed that those proteins were involved in several metabolic pathways including oxidative phosphorylation,non-alcoholic fatty liver disease(NAFLD),PI3K-Akt signaling pathway,cAMP signaling pathway,cGMP-PKG signaling pathway.CONCLUSION The proteomics study could provide valuable clues to help us to understand the hypolipidemic mechanisms of LRTPG much better.
