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The unified power quality conditioner (UPQC) has become one of the most proficient solutions for compensating the effects of voltage fluctuations, harmonics, sudden load changes and enhancing the power quality of distribution networks. Aiming at the shortcomings of conventional compensation control strategies and enhancing the compensation effect of UPQC, this paper proposes an effective control strategy for UPQC based on dq0 detection method. Furthermore, the space vector pulse width modulation (SVPWM) algorithm is improved in this paper. The fundamental and harmonic detection on the power supply side current and load side voltage are performed through the proposed strategy. In order to verify the effectiveness of the proposed control strategy, the simulation model of the system is established by MATLAB/Simulink under three-phase voltage unbalance conditions, voltage sag and load sudden changes. In addition, an experimental verification is carried out on an installed experimental platform. Under normal and unbalance operating conditions of the three-phase power supply voltage, the proposed control strategy has a better fundamental and harmonic detection effect compared with the conventional detection-based control strategy. Furthermore, under different load sudden changes conditions, it is verified that the proposed control strategy has better voltage tracking performance. Finally, the outcomes showed the effectiveness of the proposed control strategy in maintaining load side voltage stability, maintaining power side current sinusoidal, and enhancing the power quality of the distribution network.

With three dimensional uniform discrete curvelet transform (3D-UDCT) and spatial-temporal structure tensor, a novel video fusion algorithm for videos with static background images is proposed in this paper. Firstly, the 3D-UDCT is employed to decompose source videos into many subbands with different scales and directions. Secondly, corresponding subbands of source videos are merged with different fusion schemes. Finally, the fused video is obtained by the reverse 3D-UDCT. Especially, when bandpass directional subband coefficients are merged, a spatial-temporal salience detection algorithm based on the structure tensor is performed. And each subband is divided into three types of regions, i.e., regions with temporal moving targets, regions with spatial features of background images, and smooth regions. Then different fusion rules are designed for each type of regions. Compared with some existing fusion methods, the proposed fusion algorithm can not only extract more spatial-temporal salient features from input videos but also perform better in spatial-temporal consistency. In addition, the proposed fusion algorithm can also be extended to fuse videos with dynamic background images by a simple modification. Several sets of experimental results demonstrate the feasibility and validity of the proposed fusion method.