The voltage source converter based high voltage direct current(VSC-HVDC)system is based on voltage source converter,and its control system is more complex.Also affected by the fast control of power electronics,oscilla...The voltage source converter based high voltage direct current(VSC-HVDC)system is based on voltage source converter,and its control system is more complex.Also affected by the fast control of power electronics,oscillation phenomenon in wide frequency domain may occur.To address the problem of small signal stability of the VSCHVDC system,a converter control strategy is designed to improve its small signal stability,and the risk of system oscillation is reduced by attaching a damping controller and optimizing the control parameters.Based on the modeling of the VSC-HVDC system,the general architecture of the inner and outer loop control of the VSCHVDC converter is established;and the damping controllers for DC control and AC control are designed in the phase-locked loop and the inner and outer loop control parts respectively;the state-space statemodel of the control system is established to analyze its performance.And the electromagnetic transient simulation model is built on the PSCAD/EMTDC simulation platform to verify the accuracy of the small signal model.The influence of the parameters of each control part on the stability of the system is summarized.The main control parts affecting stability are optimized for the phenomenon of oscillation due to changes in operation mode occurring on the AC side due to faults and other reasons,which effectively eliminates system oscillation and improves system small signal stability,providing a certain reference for engineering design.展开更多
Purpose:Our previous study has shown that PTPRZ1-MET(ZM)fusion is a viable target for MET inhibitors in gliomas.However,the diversity and prevalence of somatic MET alterations in difuse gliomas are still elusive and n...Purpose:Our previous study has shown that PTPRZ1-MET(ZM)fusion is a viable target for MET inhibitors in gliomas.However,the diversity and prevalence of somatic MET alterations in difuse gliomas are still elusive and need to be extensively characterized for identifying novel therapeutic targets.Methods:Totally,1,350 glioma patients and 31 patient-derived cells were collected from the Chinese Glioma Genome Atlas(CGGA)and published data.All kinds of MET fusions and/or splicing variants(MET F/SVs)were identifed by bioinformatical methods.Single-cell RNA sequencing(scRNA-seq)were used for validation.In vitro experiments of drug resistance were conducted for the possibility of MET-targeted treatment.Results:MET F/SVs but not genomic amplifcation,were highly enriched in the secondary glioblastomas(sGBM)and marked worse prognosis.Further molecular and scRNA-seq analysis revealed that MET F/SVs were induced in the course of glioma evolution and highly associated with MET overexpression.Subsequent in vitro and the clinical study showed that cells and patients harboring MET F/SVs have better response to MET inhibitors.Conclusion:Our fndings expanded the percentage of gliomas with abnormal MET alterations and suggested that a subgroup of gliomas harboring MET F/SVs may beneft from MET-targeted therapy.展开更多
基金supported by Research on the Oscillation Mechanism and Suppression Strategy of Yu-E MMC-HVDC Equipment and System(2021Yudian Technology 33#).
文摘The voltage source converter based high voltage direct current(VSC-HVDC)system is based on voltage source converter,and its control system is more complex.Also affected by the fast control of power electronics,oscillation phenomenon in wide frequency domain may occur.To address the problem of small signal stability of the VSCHVDC system,a converter control strategy is designed to improve its small signal stability,and the risk of system oscillation is reduced by attaching a damping controller and optimizing the control parameters.Based on the modeling of the VSC-HVDC system,the general architecture of the inner and outer loop control of the VSCHVDC converter is established;and the damping controllers for DC control and AC control are designed in the phase-locked loop and the inner and outer loop control parts respectively;the state-space statemodel of the control system is established to analyze its performance.And the electromagnetic transient simulation model is built on the PSCAD/EMTDC simulation platform to verify the accuracy of the small signal model.The influence of the parameters of each control part on the stability of the system is summarized.The main control parts affecting stability are optimized for the phenomenon of oscillation due to changes in operation mode occurring on the AC side due to faults and other reasons,which effectively eliminates system oscillation and improves system small signal stability,providing a certain reference for engineering design.
基金supported by grants from the Natural Science Foundation of China (NSFC)/Research Grants Council (RGC),Hong Kong,China Joint Research Scheme (81761168038)the National Natural Science Foundation of China (81802994,81903078,81972337,81972816,82002647,82192894,82103623,and 82002994)+3 种基金the Mainland-Hong Kong Joint Funding Scheme ITC grant MHP/004/19 and MOST grant 2019YFE0109400the Beijing Natural Science Foundation (JQ20030)Sino-German Center for Research Promotion (M-0020)the Beijing Nova Program (Z201100006820118).
文摘Purpose:Our previous study has shown that PTPRZ1-MET(ZM)fusion is a viable target for MET inhibitors in gliomas.However,the diversity and prevalence of somatic MET alterations in difuse gliomas are still elusive and need to be extensively characterized for identifying novel therapeutic targets.Methods:Totally,1,350 glioma patients and 31 patient-derived cells were collected from the Chinese Glioma Genome Atlas(CGGA)and published data.All kinds of MET fusions and/or splicing variants(MET F/SVs)were identifed by bioinformatical methods.Single-cell RNA sequencing(scRNA-seq)were used for validation.In vitro experiments of drug resistance were conducted for the possibility of MET-targeted treatment.Results:MET F/SVs but not genomic amplifcation,were highly enriched in the secondary glioblastomas(sGBM)and marked worse prognosis.Further molecular and scRNA-seq analysis revealed that MET F/SVs were induced in the course of glioma evolution and highly associated with MET overexpression.Subsequent in vitro and the clinical study showed that cells and patients harboring MET F/SVs have better response to MET inhibitors.Conclusion:Our fndings expanded the percentage of gliomas with abnormal MET alterations and suggested that a subgroup of gliomas harboring MET F/SVs may beneft from MET-targeted therapy.
