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With the rapid development of distributed power generation with renewable energy as the core, the proportion of energy storage stations connected to the grid is constantly increasing. The access of a large number of energy storage stations will inevitably affect the voltage level and line flow level of the distribution network. Therefore, by reasonably optimizing the access location and capacity of the energy storage station to ensure that its impact on the distribution network is optimal. On this basis, this article uses a multiobjective optimization method to define the minimum voltage deviation, the optimal transmission line margin, and the minimum network loss as the optimization goals. And the firework algorithm is used to solve the problem, and the best access location and access capacity of the energy storage station are obtained. Finally, the IEEE35 node case is used in MATLAB to carry out the simulation calculation to prove the validity of the conclusion. Therefore, the planning scheme of energy storage station proposed in this article has effective theoretical significance and practical value.

When a large-scale interconnected system encounters a major disturbance, it will actively disassociate, and the receiving-end power grid will suffer from serious shortage of active power and a significant drop in frequency. Emergency control measures need to be taken to ensure the stability of the receiving-end power grid system. First, according to the different control characteristics of the generator's primary frequency modulation, pumped storage power station, and low-frequency load shedding, the mathematical model of the emergency control strategy is formulated. Then, according to the characteristics of the active disassembly of the power grid, the equation constraints in the model are simplified, and the heuristic algorithm with the participation factor as the basic element is used to calculate how the resources of the strategy are allocated and input to obtain the quantitative indicators of each resource. Finally, the feasibility of multi-resource frequency stability control and section correction control strategies is verified and compared through IEEE39 node simulation. The simulation results show that the coordinated implementation of multiple resources can ensure timely control of the system frequency and minimize the failure loss; at the same time, considering that the power limit is exceeded and the power transfer of the receiving end is too large, the section correction control is proposed Strategy has a great optimization effect.

This paper analyzes and evaluates the toughness of the distribution network, and briefly introduces measures to improve the distribution network: First, it briefly analyzes the impact of extreme environment on the distribution network, and proposes the concept of toughness of the distribution network. Then distinguish it from the reliability of the distribution network, select indicators and attributes to measure the flexibility of the distribution network, and build a model of the distribution network components and strong winds. Secondly, from the perspective of strengthening distribution network components, microgrids, and reserve energy to improve the toughness of the distribution network, a brief introduction is given to the distribution network enhancement strategy. Then establish the distribution network toughness evaluation model, and finally use specific calculation examples to conduct the toughness evaluation and analysis of the selected distribution network under extreme environment, and calculate the distribution ratio of the distribution network under normal weather conditions.

In this paper,we introduce a robust image watermarking method based on Hilbert-Huang Transform against geometric distortion. This watermarking is detected by a linear frequency change. The Hilbert-Huang transformation is used to detect the watermark. The chirp signals are used as watermarks and this type of signals is resistant to all stationary filtering methods and exhibits geometrical symmetry. In the two-dimensional Radon-Wigner transformation domain, the chirp signals used as watermarks change only its position in space/spatial-frequency distribution,after applying linear geometrical attack,such as scale rotation and cropping. But the two-dimensional Radon-Wigner transformation needs too much difficult computing. So the image is put into a series of 1D signal by choosing scalable local time windows. The watermark embedded in the HHT transformation domain. The watermark thus generated is invisible and performs well in StirMark test and is robust to geometrical attacks. Compared with other watermarking algorithms,this algorithm is more robust, especially against geometric distortion, while having excellent frequency properties.

In this paper, a robust image watermarking method in two-dimensional space/spatial-frequency distributions domain is proposed which is robust against geometric distortion. This watermarking is detected by a linear frequency change. The chirp let transformation is used to detect the watermark. The chirp signals are used as watermarks and this type of signals is resistant to all stationary filtering methods and exhibits geometrical symmetry. In the two-dimensional Radon-Wigner transformation domain, the chirp signals used as watermarks change only its position in space/spatial-frequency distribution, after applying linear geometrical attack, such as scale rotation and cropping. But the two-dimensional Radon-Wigner transformation needs too much difficult computing. So the image is put into a series of 1D signals by choosing scalable local time windows. The watermark embedded in the chirp let transformation domain. The watermark thus generated is invisible and performs well in Stir Mark test and is robust to geometrical attacks. Compared with other watermarking algorithms, this algorithm is more robust, especially against geometric distortion, while having excellent frequency properties.

In this paper, a robust image watermarking method in two-dimensional space/spatial-frequency distributions domain is proposed which is robust against geometric distortion. This watermarking is detected by a linear frequency change. The Doppler let transformation is used to detect the watermark. The chirp signals are used as watermarks and this type of signals is resistant to all stationary filtering methods and exhibits geometrical symmetry. In the two-dimensional Radon-Wigner transformation domain, the chirp signals used as watermarks change only its position in space/spatial-frequency distribution, after applying linear geometrical attack, such as scale rotation and cropping. But the two-dimensional Radon-Wigner transformation needs too much difficult computing. So the image is put into a series of 1D signals by choosing scalable local time windows. The watermark embedded in the Doppler let transformation domain. The watermark thus generated is invisible and performs well in StirMark test and is robust to geometrical attacks. Compared with other watermarking algorithms, this algorithm is more robust, especially against geometric distortion, while having excellent frequency properties.

In this paper, we introduce a robust watermark scheme against shearing attack for digital images based on video series wavelet transform. Based on the characteristics of the image theory and human visual system, the proposed method make use of the there-dimensional video wavelet transform to split the image to a sense of image videos and the watermark is adaptively weighed to the different positions of the middle frequency region. The method makes use of the characteristics of image 2D wavelet transform and the person’s sense of vision and shows excellent advantage against shearing attack. The method could show the watermark clearly when more than half of the image has been cut. Experimental results show this method excellent robustness for image shearing. The goal of this paper is to achieve robust digital image watermark against shearing. The algorithm performs well in StirMark test and is robust to geometrical attacks.

In this paper, a robust digital watermarking algorithm against shearing is introduced. The proposed method makes use of the complete generalized orthogonal properties of orthogonal function system to achieve the piece-based orthogonal transform on the image. To strengthen the robustness of watermark, the significant middle frequently coefficients in the transformation matrix are picked up, based on characteristics of the image visual system. The watermark is adoptively weighed to the middle frequently matrix. The method improves the validity of watermarking and shows excellent advantage against shearing attack. Experimental results show that The watermark thus generated is invisible and performs well in StirMark test and is robust to geometrical attacks.