scholarly journals Complex Design Method of Filtration Station Considering Harmonic Components

Energies ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5872
Author(s):  
Vaclav Kus ◽  
Bohumil Skala ◽  
Pavel Drabek

The paper deals with a new methodology for calculating the filter parameters. The basis is respect for the fact that the real filter current consists of other harmonic components, which filter is tuned. The proposed methodology was used to design filters for traction substation 25 kV/50 Hz. The operation of the locomotives in the AC supply systems of 25 kV/50 Hz leads to a rising of higher order harmonic currents. Due to the 1-phase supply system, these are mainly the 3rd and 5th harmonics. By simulation and subsequent measurement of the proposed traction power station filters the proposed methodology was verified. Thus, the filter design can also be used for filter compensating stations of the standard 3-phase distribution network. The described method presents an optimal filter design without unnecessary oversizing. This fact reduces the size and cost of the filter. It is shown that it is possible to design a filter that meets the requirements for power quality under extreme load and to minimise distortion of line voltage.

2003 ◽  
Vol 39 (8) ◽  
pp. 695 ◽  
Author(s):  
G. Jovanovic-Dolecek ◽  
J. Diaz-Carmona

2011 ◽  
Vol 128-129 ◽  
pp. 181-184
Author(s):  
You Lian Zhu ◽  
Cheng Huang

Design of morphological filter greatly depends on morphological operations and structuring elements selection. A filter design method used median closing morphological operation is proposed to enhance the image denoising ability and the PSO algorithm is introduced for structural elements selecting. The method takes the peak value signal-to-noise ratio (PSNR) as the cost function and may adaptively build unit structuring elements with zero square matrix. Experimental results show the proposed method can effectively remove impulse noise from a noisy image, especially from a low signal-to-noise ratio (SNR) image; the noise reduction performance has obvious advantages than the other.


Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1880
Author(s):  
Elia Brescia ◽  
Donatello Costantino ◽  
Paolo Roberto Massenio ◽  
Vito Giuseppe Monopoli ◽  
Francesco Cupertino ◽  
...  

Permanent magnet machines with segmented stator cores are affected by additional harmonic components of the cogging torque which cannot be minimized by conventional methods adopted for one-piece stator machines. In this study, a novel approach is proposed to minimize the cogging torque of such machines. This approach is based on the design of multiple independent shapes of the tooth tips through a topological optimization. Theoretical studies define a design formula that allows to choose the number of independent shapes to be designed, based on the number of stator core segments. Moreover, a computationally-efficient heuristic approach based on genetic algorithms and artificial neural network-based surrogate models solves the topological optimization and finds the optimal tooth tips shapes. Simulation studies with the finite element method validates the design formula and the effectiveness of the proposed method in suppressing the additional harmonic components. Moreover, a comparison with a conventional heuristic approach based on a genetic algorithm directly coupled to finite element analysis assesses the superiority of the proposed approach. Finally, a sensitivity analysis on assembling and manufacturing tolerances proves the robustness of the proposed design method.


2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Yifu Feng ◽  
Zhi-Min Li ◽  
Xiao-Heng Chang

This paper investigates the problem of H∞ filtering for class discrete-time Lipschitz nonlinear singular systems with measurement quantization. Assume that the system measurement output is quantized by a static, memoryless, and logarithmic quantizer before it is transmitted to the filter, while the quantizer errors can be treated as sector-bound uncertainties. The attention of this paper is focused on the design of a nonlinear quantized H∞ filter to mitigate quantization effects and ensure that the filtering error system is admissible (asymptotically stable, regular, and causal), while having a unique solution with a prescribed H∞ noise attenuation level. By introducing some slack variables and using the Lyapunov stability theory, some sufficient conditions for the existence of the nonlinear quantized H∞ filter are expressed in terms of linear matrix inequalities (LMIs). Finally, a numerical example is presented to demonstrate the effectiveness of the proposed quantized filter design method.


2011 ◽  
Vol 2011 (CICMT) ◽  
pp. 000043-000049
Author(s):  
Ehab Abousaif ◽  
Aicha Elshabini ◽  
Fred Barlow

Microwave filters are generally designed with microwave transmission lines. However these filters are typically lossy. The waveguide filters using conventional inductive elements such as metal rods and transverse diaphragm have some disadvantages such as complicated structure, high cost and they can be hard to mass produce. But they also have many advantages such as the capability of high power transmission, a non-radiating structure, and their thermal efficiency. A novel waveguide inductive strip filter embedded in LTCC is introduced in this paper where the disadvantages of the conventional waveguide filters are eliminated. By using LTCC technology, the cost will typically be lower, it can easily be mass produce, and these designs can also be tested easily. The equivalent T-network parameters of the inductive strip mounted in a waveguide and embedded in LTCC substrate were derived. A new iterative technique was used based on the Variation principle. The design formulas and curves of the filter were presented. The design method of the filter was derived by applying the equivalent network of the inductive strip to the usual method of the filter design. A complete set of new curves relating the various filter parameters were introduced. Similar curves can be derived to design similar filters for any frequency band using any dielectric material. Three-dimensional electromagnetic field modeling and simulation was carried out using HFSS (High Frequency Structure Simulator). An optimization process was done for the designed filter. The modeling and the optimization S-parameters curves are shown. This paper introduces a new methodology of designing waveguide inductive strip filters embedded in LTCC. The design methodology was derived and presented with formulas and curves. The design steps are explained and verified by examples and results.


Author(s):  
Ryohei Yokoyama ◽  
Masashi Ohkura ◽  
Tetsuya Wakui

In designing energy supply systems, designers should consider that energy demands and costs as parameters have some uncertainties, evaluate the robustness in system performances against the uncertainties, and design the systems rationally to heighten the robustness. A robust optimal design method of energy supply systems under only uncertain energy demands was revised so that it can be applied to systems with complex configurations and large numbers of periods for variations in energy demands. In addition, a method of comparing performances of two energy supply systems under only uncertain energy demands was proposed by utilizing a part of the revised robust optimal design method. In this paper, the revised robust optimal design method as well as the proposed performance comparison method are extended so that they can be applied to the robust optimal design and the performance comparison of energy supply systems under not only uncertain energy demands but also uncertain energy costs. Through a case study on a gas turbine cogeneration system for district energy supply, the validity and effectiveness of the extended optimal design method and features of the robust optimal design are clarified. In addition, the gas turbine cogeneration system is compared with a conventional energy supply system using the extended performance comparison method.


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