Excitation regulator has played an important role to ensure that generator run safely and stably. However, in some remote areas, the rural small generator excitation control system is very backward, and it has hindere...Excitation regulator has played an important role to ensure that generator run safely and stably. However, in some remote areas, the rural small generator excitation control system is very backward, and it has hindered the development of Chinese agriculture and the pace of new countryside construction. This paper introduced a kind of structure and basic principle of DSP-based automatic excitation regulator, which was applied to rural small generator. We chose TMS320LF2407A chip as the core of regulator control system; the regulator adjusted PWM based on PID control strategy to control the exciting current. The theoretical analysis showed that the regulator had the characteristics of simplicity and reliability, well dynamic and static characteristics, and it could also adjust its own state quickly. The result was applicable to small rural hydropower station.展开更多
Three new lanthanide-organic compounds, namely, [Ln_2(OH)_2(oba)(2-pc)_2]n(Ln =Er(1), Ho(2), and Dy(3))(oba = 4,4?-oxybis(benzoate), 2-pc = 2-pyrazinecarboxylic acid) have been obtained under hydrothermal conditions. ...Three new lanthanide-organic compounds, namely, [Ln_2(OH)_2(oba)(2-pc)_2]n(Ln =Er(1), Ho(2), and Dy(3))(oba = 4,4?-oxybis(benzoate), 2-pc = 2-pyrazinecarboxylic acid) have been obtained under hydrothermal conditions. These compounds are isostructural and exhibit 2 D layered structures by incorporating [Ln_4(μ_3-OH)_4]^(8+) clusters and the mixed linkers of oba and 2-pc. It is interesting that decarboxylation occurred in the ortho position and 2,3-pyrazinedicarboxylic acid was partially transformed into 2-pc under hydrothermal conditions. Compound 3 emits a typical Dy^(3+) emission spectrum. Furthermore, the PXRD, TGA and IR spectra were also studied.展开更多
文摘Excitation regulator has played an important role to ensure that generator run safely and stably. However, in some remote areas, the rural small generator excitation control system is very backward, and it has hindered the development of Chinese agriculture and the pace of new countryside construction. This paper introduced a kind of structure and basic principle of DSP-based automatic excitation regulator, which was applied to rural small generator. We chose TMS320LF2407A chip as the core of regulator control system; the regulator adjusted PWM based on PID control strategy to control the exciting current. The theoretical analysis showed that the regulator had the characteristics of simplicity and reliability, well dynamic and static characteristics, and it could also adjust its own state quickly. The result was applicable to small rural hydropower station.
文摘Three new lanthanide-organic compounds, namely, [Ln_2(OH)_2(oba)(2-pc)_2]n(Ln =Er(1), Ho(2), and Dy(3))(oba = 4,4?-oxybis(benzoate), 2-pc = 2-pyrazinecarboxylic acid) have been obtained under hydrothermal conditions. These compounds are isostructural and exhibit 2 D layered structures by incorporating [Ln_4(μ_3-OH)_4]^(8+) clusters and the mixed linkers of oba and 2-pc. It is interesting that decarboxylation occurred in the ortho position and 2,3-pyrazinedicarboxylic acid was partially transformed into 2-pc under hydrothermal conditions. Compound 3 emits a typical Dy^(3+) emission spectrum. Furthermore, the PXRD, TGA and IR spectra were also studied.
