针对传统永磁同步电机(permanent magnet synchronous motor,PMSM)三矢量模型预测电流控制(three-vector model predictive current control,TV-MPCC)存在开关频率不固定和计算复杂的问题,提出一种固定开关频率TV-MPCC策略。利用前一周...针对传统永磁同步电机(permanent magnet synchronous motor,PMSM)三矢量模型预测电流控制(three-vector model predictive current control,TV-MPCC)存在开关频率不固定和计算复杂的问题,提出一种固定开关频率TV-MPCC策略。利用前一周期的零电压矢量和参考电压矢量所在扇区来快速筛选所需最优电压矢量和次优电压矢量,避免了无效枚举计算,从而降低了开关频率和计算复杂度。引入系统d和q轴电流差参数,计算各电压矢量的作用时间,确保电压矢量作用时间恒大于零和开关频率固定。以三相两电平电压型逆变器驱动的表贴式PMSM为被控对象,通过仿真和实验对传统TV-MPCC策略和所提三矢量固定开关频率模型预测电流控制策略进行对比研究,仿真和实验结果表明,所提策略在保证系统稳态和动态性能的基础上,在固定和降低开关频率的同时,降低了计算复杂度。展开更多
A new ruthenium（Ⅱ） complex,[Ru（bpy）2bdpq](ClO4)2,where bpy=2,2′-bipyridine,（bdpq=2-（benzoxazol-2-yl）-dipyrido） [2,3-f: 2′,3′-h]quinoxaline,was synthesized and characterized by IR,（）1H NMR,MALDI-TOF MS,an...A new ruthenium（Ⅱ） complex,[Ru（bpy）2bdpq](ClO4)2,where bpy=2,2′-bipyridine,（bdpq=2-（benzoxazol-2-yl）-dipyrido） [2,3-f: 2′,3′-h]quinoxaline,was synthesized and characterized by IR,（）1H NMR,MALDI-TOF MS,and elemental analysis.The electronic absorption and emission spectral titrations with calf thymus DNA,steady-state emission quenching by [Fe（CN）6]4-,and viscosity measurements were carried out to study the binding of [Ru（bpy）2bdpq](ClO4)2 with the DNA.The results indicate that the（Ru（Ⅱ）） complex acts as a DNA intercalator with a binding constant of（1.9±0.1）×106 L/mol at 50 mmol/L NaCl,and can serve as a good "DNA molecular light switches" with a luminescence enhancement factor of 180.展开更多
The formation of heterobimetallic ruthenium?complex was investigated by absorption and emission spectra. As an intercalator of DNA, the luminescent monometallic ruthenium?complex [Ru(bpy)2tpphz]2+could coordinate with...The formation of heterobimetallic ruthenium?complex was investigated by absorption and emission spectra. As an intercalator of DNA, the luminescent monometallic ruthenium?complex [Ru(bpy)2tpphz]2+could coordinate with Zn2+to form the nonluminescent heterobimetallic complex [Ru(bpy)2(tpphz)Zn]4+. The emission intensity of complex decreased as increasing the amounts of Zn2+and the luminescence was almost lost at the ratio of / of 1. After binding to DNA, the peripheral coordination site on the tpphz ligand remained accessible for Zn2+, the coordination occurred from the oppsite side of helix with respect to intercalated [Ru(bpy)2tpphz]2+and the nonluminescent heterobimetallic complex was formed. On the other hand, the [Ru(bpy)2(tpphz)Zn]4+also bound to DNA by intercalation and situated the region of the intercalated [Ru(bpy)2tpphz]2+between the base pairs of DNA. The complex looked like a molecular nut (the Zn2+) and bolt (the [Ru(bpy)2tpphz]2+).展开更多
文摘针对传统永磁同步电机(permanent magnet synchronous motor,PMSM)三矢量模型预测电流控制(three-vector model predictive current control,TV-MPCC)存在开关频率不固定和计算复杂的问题,提出一种固定开关频率TV-MPCC策略。利用前一周期的零电压矢量和参考电压矢量所在扇区来快速筛选所需最优电压矢量和次优电压矢量,避免了无效枚举计算,从而降低了开关频率和计算复杂度。引入系统d和q轴电流差参数,计算各电压矢量的作用时间,确保电压矢量作用时间恒大于零和开关频率固定。以三相两电平电压型逆变器驱动的表贴式PMSM为被控对象,通过仿真和实验对传统TV-MPCC策略和所提三矢量固定开关频率模型预测电流控制策略进行对比研究,仿真和实验结果表明,所提策略在保证系统稳态和动态性能的基础上,在固定和降低开关频率的同时,降低了计算复杂度。
文摘A new ruthenium（Ⅱ） complex,[Ru（bpy）2bdpq](ClO4)2,where bpy=2,2′-bipyridine,（bdpq=2-（benzoxazol-2-yl）-dipyrido） [2,3-f: 2′,3′-h]quinoxaline,was synthesized and characterized by IR,（）1H NMR,MALDI-TOF MS,and elemental analysis.The electronic absorption and emission spectral titrations with calf thymus DNA,steady-state emission quenching by [Fe（CN）6]4-,and viscosity measurements were carried out to study the binding of [Ru（bpy）2bdpq](ClO4)2 with the DNA.The results indicate that the（Ru（Ⅱ）） complex acts as a DNA intercalator with a binding constant of（1.9±0.1）×106 L/mol at 50 mmol/L NaCl,and can serve as a good "DNA molecular light switches" with a luminescence enhancement factor of 180.
文摘The formation of heterobimetallic ruthenium?complex was investigated by absorption and emission spectra. As an intercalator of DNA, the luminescent monometallic ruthenium?complex [Ru(bpy)2tpphz]2+could coordinate with Zn2+to form the nonluminescent heterobimetallic complex [Ru(bpy)2(tpphz)Zn]4+. The emission intensity of complex decreased as increasing the amounts of Zn2+and the luminescence was almost lost at the ratio of / of 1. After binding to DNA, the peripheral coordination site on the tpphz ligand remained accessible for Zn2+, the coordination occurred from the oppsite side of helix with respect to intercalated [Ru(bpy)2tpphz]2+and the nonluminescent heterobimetallic complex was formed. On the other hand, the [Ru(bpy)2(tpphz)Zn]4+also bound to DNA by intercalation and situated the region of the intercalated [Ru(bpy)2tpphz]2+between the base pairs of DNA. The complex looked like a molecular nut (the Zn2+) and bolt (the [Ru(bpy)2tpphz]2+).
