Conventional multilevel inverters often suffer from high harmonic distortion and increased design complexity due to the need for numerous power semiconductor components,particularly at elevated voltage levels.Addressi...Conventional multilevel inverters often suffer from high harmonic distortion and increased design complexity due to the need for numerous power semiconductor components,particularly at elevated voltage levels.Addressing these shortcomings,thiswork presents a robust 15-level PackedUCell(PUC)inverter topology designed for renewable energy and grid-connected applications.The proposed systemintegrates a sensor less proportional-resonant(PR)controller with an advanced carrier-based pulse width modulation scheme.This approach efficiently balances capacitor voltage,minimizes steady-state error,and strongly suppresses both zero and third-order harmonics resulting in reduced total harmonic distortion and enhanced voltage regulation.Additionally,a novel switching algorithm simplifies the design and implementation,further lowering voltage stress across switches.Extensive simulation results validate the performance under various resistive and resistive-inductive load conditions,demonstrating compliance with IEEE-519 THD standards and robust operation under dynamic changes.The proposed sensorless PR-controlled 15-PUC inverter thus offers a compelling,cost-effective solution for efficient power conversion in next-generation renewable energy systems.展开更多
Citrus canker,caused by Xanthomonas citri subsp.citri(Xcc),is a globally quarantine disease infecting nearly all Citrus cultivars.Citron C-05 has been identified with complete and active resistance to Xcc.However,the ...Citrus canker,caused by Xanthomonas citri subsp.citri(Xcc),is a globally quarantine disease infecting nearly all Citrus cultivars.Citron C-05 has been identified with complete and active resistance to Xcc.However,the mechanism underlying Citron C-05's resistance to Xcc remains elusive.We identified a gene cluster on chromosome 8 of the citrus genome comprising five pathogenesis-related 4-like genes.PR4A was upregulated in Citron C-05 leaves under Xcc infection,exhibiting the highest expression among these PR4-like genes.In addition,PR4A expression was higher in leaves of disease-resistant genotypes than susceptible genotypes under Xcc invasion.Bimolecular fluorescence complementation(BiFC)and Split-Luc assays indicated that CmWRKY75,a positive regulator of PR4A,interacted with pthA4 and upregulated expression of PR4A in Citron C-05 leaves.Regulatory function for the expression of CmPR4A was localized to a 516-nucleotide region upstream of the translational start site,which was designated Pro CmPR4A-P516.Transient overexpression of CmPR4A improved resistance to Xcc in sweet orange,and three transgenic lines of OE-CmPR4A exhibited resistance to Pseudomonas syringae pv.tomato DC3000(Pst DC3000)in Arabidopsis.Furthermore,CmSMU2 was identified through yeast two-hybrid library using CmPR4A as bait,Bi FC and Split-Luc assays further verified their interaction.Transient overexpression of CmSMU2 in sweet orange increased resistance to Xcc.Co-expression of CmSMU2 and CmPR4A enhanced accumulation of reactive oxygen species compared to CmSMU2 or CmPR4A,indicating that they may synergistically enhance resistance to Xcc in citrus.These findings lay the groundwork for a theoretical analysis of the mechanism underlying the resistance of Citron C-05 against citrus canker.展开更多
文摘Conventional multilevel inverters often suffer from high harmonic distortion and increased design complexity due to the need for numerous power semiconductor components,particularly at elevated voltage levels.Addressing these shortcomings,thiswork presents a robust 15-level PackedUCell(PUC)inverter topology designed for renewable energy and grid-connected applications.The proposed systemintegrates a sensor less proportional-resonant(PR)controller with an advanced carrier-based pulse width modulation scheme.This approach efficiently balances capacitor voltage,minimizes steady-state error,and strongly suppresses both zero and third-order harmonics resulting in reduced total harmonic distortion and enhanced voltage regulation.Additionally,a novel switching algorithm simplifies the design and implementation,further lowering voltage stress across switches.Extensive simulation results validate the performance under various resistive and resistive-inductive load conditions,demonstrating compliance with IEEE-519 THD standards and robust operation under dynamic changes.The proposed sensorless PR-controlled 15-PUC inverter thus offers a compelling,cost-effective solution for efficient power conversion in next-generation renewable energy systems.
基金supported by the National Natural Science Foundation of China(32402500 and 31741110)the Scientific Research Fund of Hunan Provincial Education Department,China(21B0220)。
文摘Citrus canker,caused by Xanthomonas citri subsp.citri(Xcc),is a globally quarantine disease infecting nearly all Citrus cultivars.Citron C-05 has been identified with complete and active resistance to Xcc.However,the mechanism underlying Citron C-05's resistance to Xcc remains elusive.We identified a gene cluster on chromosome 8 of the citrus genome comprising five pathogenesis-related 4-like genes.PR4A was upregulated in Citron C-05 leaves under Xcc infection,exhibiting the highest expression among these PR4-like genes.In addition,PR4A expression was higher in leaves of disease-resistant genotypes than susceptible genotypes under Xcc invasion.Bimolecular fluorescence complementation(BiFC)and Split-Luc assays indicated that CmWRKY75,a positive regulator of PR4A,interacted with pthA4 and upregulated expression of PR4A in Citron C-05 leaves.Regulatory function for the expression of CmPR4A was localized to a 516-nucleotide region upstream of the translational start site,which was designated Pro CmPR4A-P516.Transient overexpression of CmPR4A improved resistance to Xcc in sweet orange,and three transgenic lines of OE-CmPR4A exhibited resistance to Pseudomonas syringae pv.tomato DC3000(Pst DC3000)in Arabidopsis.Furthermore,CmSMU2 was identified through yeast two-hybrid library using CmPR4A as bait,Bi FC and Split-Luc assays further verified their interaction.Transient overexpression of CmSMU2 in sweet orange increased resistance to Xcc.Co-expression of CmSMU2 and CmPR4A enhanced accumulation of reactive oxygen species compared to CmSMU2 or CmPR4A,indicating that they may synergistically enhance resistance to Xcc in citrus.These findings lay the groundwork for a theoretical analysis of the mechanism underlying the resistance of Citron C-05 against citrus canker.
