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The dead-time effects of single-phase rectifier causes voltage and current distortions, zero-current clamping effects,etc. To solve the problems, the dead-time and zero-current clamping effects were analyzed, and a novel dead time compensation method of single-phase PWM rectifier was proposed by the observation of grid input voltage based on resonant controller phase-looked loop. The new method avoids the noise of the current detection, so that zero-crossing detection is more accurate, and does not cause the phase delay. Comparative analysis was conducted with traditional dead time compensation method based on the current. The proposed scheme can effectively improve the degree of sinusoidal current waveform, and eliminate the need to detect the direction of the current conventional solutions drawbacks. This algorithm is simple and has a practical value. The simulation and experiment results show that the grid input current total harmonic distortion with grid input voltage observation is lower and compensation effect is better. [ABSTRACT FROM AUTHOR]

A new dinuclear bromido-coordinated Schiff base zinc(II) complex, [Zn2Br2L1(MeOH)]·MeOH (1), and a new mononuclear bromido-coordinated Schiff base zinc(II) complex, [ZnBr2L2] (2), where L1is the dianionic form ofN,N’-bis(5-fluoro-2-hydroxybenzylidene)propane-1,3-diamine (H2L1), and L2is the zwitterionic form of 2-[(3-dimethylammoniopropylimino)methyl]-4-fluorophenol, have been preprared and characterized mainly by single-crystal X-ray diffraction. Complex 1 crystallizes in the monoclinic space groupP21/nwith unit cell dimensionsa= 10.0876(9) Å,b= 8.9549(8) Å,c= 26.586(2) Å, β = 95.134(2)º, V = 2391.9(4) Ǻ3, Z = 4,R1= 0.0547, andwR2= 0.1025. Complex 2 crystallizes in the monoclinic space groupP21/cwith unit cell dimensionsa= 7.359(1) Å,b= 13.798(2) Å,c= 17.676(2) Å, β = 114.602(2)º, V = 1631.8(4) Ǻ3, Z = 4,R1= 0.0877, andwR2= 0.2197. The inner Zn atom in 1 is five-coordinated in a square pyramidal geometry. The outer Zn atom in 1 and the Zn atom in 2 are four-coordinated in tetrahedral geometry. The crystals of the complexes are stabilized by intermolecular hydrogen bonds. [ABSTRACT FROM PUBLISHER]