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Fault Detection and Classification for Transmission Line Protection System Using Artificial Neural Network
Issue:
Volume 4, Issue 5, October 2016
Pages:
89-96
Received:
9 September 2016
Accepted:
23 September 2016
Published:
19 October 2016
Abstract: The artificial neural network is a powerful tool for the detection of the transmission line faults due to its ability to differentiate between various patterns. This paper deals with the application of artificial neural networks (ANNs) to the fault detection and classification in high voltage transmission lines for high speed protection which can be used in digital power system protection. The three phase currents of one end are taken as inputs in the proposed scheme. The feed forward neural network along with back propagation algorithm has been employed for detection and classification of the fault for analysis of each of the three phases involved in the process. The ANN was trained and tested using various sets of field data, which was obtained from the simulation of faults at various fault scenarios (fault types, fault locations and fault resistance) of 230 kV, 193.2 km in length “Mansan-Shwesaryan, Mandalay Region, Myanmar” transmission line using a computer program based on MATLAB/Simulink. Simulation results confirm that the proposed method can efficiently be used for accurate fault classification on the transmission line.
Abstract: The artificial neural network is a powerful tool for the detection of the transmission line faults due to its ability to differentiate between various patterns. This paper deals with the application of artificial neural networks (ANNs) to the fault detection and classification in high voltage transmission lines for high speed protection which can b...
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A Fuzzy Indoor Positioning System with ZigBee Wireless Sensors
Chih-Yung Chen,
Yu-Ju Chen,
Shen-Whan Chen,
Chi-Yen Shen,
Rey-Chue Hwang
Issue:
Volume 4, Issue 5, October 2016
Pages:
97-102
Received:
20 October 2016
Published:
20 October 2016
Abstract: This paper presents an indoor positioning system (IPS) by using fuzzy estimation technique. The research aims to design an IPS with high stability, high accuracy and high reliability. The received signal strengths (RSS) sensed by ZigBee wireless sensors were used to estimate the object’s position. All studies were experimented at a 10x10 square meters’ indoor field. In all experiments, 361 positions (features) were estimated. From the experimental results shown, the fuzzy positioning technique proposed has the high accurate estimation even RSS signals are unstable. It is also clearly found that the positioning accuracy could be greatly improved when more wireless sensors are used in IPS.
Abstract: This paper presents an indoor positioning system (IPS) by using fuzzy estimation technique. The research aims to design an IPS with high stability, high accuracy and high reliability. The received signal strengths (RSS) sensed by ZigBee wireless sensors were used to estimate the object’s position. All studies were experimented at a 10x10 square met...
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Analytical Performance and Characterization of a Quartz Crystal Microbalance for the Detection of Cu(II) Ions in Water
Chi-Yen Shen,
Roan Yeh,
Mei-Hui Chung,
Rey-Chue Hwang
Issue:
Volume 4, Issue 5, October 2016
Pages:
103-108
Received:
20 October 2016
Published:
20 October 2016
Abstract: A novel quartz crystal microbalance (QCM) sensor based on combining phosphate-modified dendrimer and ionophore has been developed for the determination of Cu(II) ions. The performance of the developed QCM sensor was evaluated based on frequency data and experimental results evidently indicated that the prepared sensor could be sensitive for the determination of Cu(II) ions in water. The obtained QCM sensor presents good selectivity monitoring of Cu(II) ions, short response time (40 s), and wide linear range (0.01-100 μM).
Abstract: A novel quartz crystal microbalance (QCM) sensor based on combining phosphate-modified dendrimer and ionophore has been developed for the determination of Cu(II) ions. The performance of the developed QCM sensor was evaluated based on frequency data and experimental results evidently indicated that the prepared sensor could be sensitive for the det...
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Design and Simulation of PMSM Speed Regulating System Based on SMVSC
Zhou Jianhong,
Ge Debing,
Zhang Yulong
Issue:
Volume 4, Issue 5, October 2016
Pages:
109-113
Received:
20 October 2016
Published:
20 October 2016
Abstract: Sliding mode variable structure control (SMVSC) has very strong robustness, which has been widely applied in permanent magnet synchronous motor (PMSM) speed regulating system. Constant rate reaching law approach speed is related to the sliding mode reaching gain. The higher the sliding mode reaching gain, the faster the reaching speed, and then the stronger chattering. In this paper, a new reaching law is designed on the basis of constant reaching law. With the analysis of MATLAB, the new reaching law not only increases the approach speed of the sliding mode, but also has a better inhibition effect on chattering. It provides a reference for further experiments.
Abstract: Sliding mode variable structure control (SMVSC) has very strong robustness, which has been widely applied in permanent magnet synchronous motor (PMSM) speed regulating system. Constant rate reaching law approach speed is related to the sliding mode reaching gain. The higher the sliding mode reaching gain, the faster the reaching speed, and then the...
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Propagation of Photon in Multilayer Anisotropic Metamaterials
Issue:
Volume 4, Issue 5, October 2016
Pages:
114-119
Received:
9 November 2016
Published:
10 November 2016
Abstract: We present a theoretical study of the propagation properties of polarized photons transmitting through a multilayer cavity with anisotropic metamaterials. We find that there are the resonant peaks of transmission appearing for photons polarized in a certain direction transmitting through the cavity with the anisotropic metamaterials having negative elements of the permittivity tensor. The resonant peak of transmission for photons can be achieved by adjusting the thicknesses of the cavity. The frequency of the resonant peak moves to the lower frequency as the thickness of the cavity which is the air in our designed structure increasing for a three layer cavity. The result also shows that we can adjust the resonant peak through changing the layer number. Increasing the layer number the more resonant peaks appear. The three layer system has one resonant peak. The five layer system has two resonant peaks and the seven layer system has three resonant peaks. The cavity number which also is the number of the air layer decides the resonant peaks. Increasing the cavity thickness the space of the resonant peaks will decrease. For a three layer cavity, the resonant peak will appear to a certain cavity thickness when we keep the frequency of the input photon as a constant. As the frequency of the input photon becomes bigger the thickness of the cavity corresponding to the resonant peak becomes smaller. At the same time the resonant peak becomes sharp. The result shows that the transmission is almost invariant with the changing of the thickness of the anisotropic metamaterials. This means the resonant peak is insensitive to the thickness of the anisotropic metamaterials. So the thickness of the cavity (air) is important to the design of the cavity structure. These conclusions will give us some instructions to the design of the cavity structure with the anisotropic metamaterials. The cavity structures with the anisotropic metamaterials have the potential for applying such as filters for photons with certain polarizations.
Abstract: We present a theoretical study of the propagation properties of polarized photons transmitting through a multilayer cavity with anisotropic metamaterials. We find that there are the resonant peaks of transmission appearing for photons polarized in a certain direction transmitting through the cavity with the anisotropic metamaterials having negative...
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Copyright Protection for Digital Colour Images Using Dual Watermarking Technique by Applying Improved DWT, DCT and SVD
Lakshmi Priya A.,
S. Letitia
Issue:
Volume 4, Issue 5, October 2016
Pages:
120-130
Received:
8 December 2015
Accepted:
17 December 2015
Published:
19 November 2016
Abstract: The main objective of the majority of research in Digital Image Watermarking technique is to improve the robustness of attacks.In this paper, a new algorithm has been proposed based on Discrete Wavelet Transform, Discrete Cosine Transformation in association with Singular Value Decomposition for embedding the dual watermark which provides an efficient copyright protection.Here the primary watermark is embedded into the secondary watermark and the resultant image is used as a watermark for the host or cover image. The primary and secondary watermarks are retrieved back by using an efficient watermark retrieving algorithm. During the processes of embedding the scaling factor is varied to improve the quality of watermarked image. In this proposed algorithm the watermarked image is extracted back with same quality, high peak signal to noise ratio and normalized correlation coefficients. The quality of the extracted watermarks is authenticated using Peak Signal to Noise Ratio and Normalized Correlation Coefficient. Compared with previous methods the proposed algorithm has a significantly higher robustness against various geometrical and removal attacks.Nearly 28 attacks like Cropping, Rotating at various angles, Sharpening, Motion Blur, rescaling, resizing and adding noise like Salt and Pepper noise, Gaussian noise, Spackle noise, filters like average filter, median filters are attempted. Even after attempted all such attacks both the watermarks are retrieved back with the same quality and high normalized correlation coefficient.
Abstract: The main objective of the majority of research in Digital Image Watermarking technique is to improve the robustness of attacks.In this paper, a new algorithm has been proposed based on Discrete Wavelet Transform, Discrete Cosine Transformation in association with Singular Value Decomposition for embedding the dual watermark which provides an effici...
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Closed-Loop Design for Standalone Photovoltaic-Battery Hybrid Power System
Issue:
Volume 4, Issue 5, October 2016
Pages:
131-138
Received:
22 November 2016
Published:
24 November 2016
Abstract: The photovoltaic-battery hybrid power system is constructed with photovoltaic panels and a battery, which are connected to the load via a boost converter and a bidirectional buck/boost converter, respectively. Depending on the amount of available solar power, the photovoltaic panels may operate in a maximum power point tracking (MPPT) mode or off-MPPT mode to regulate the output voltage, and at the same time, the battery may provide power to the load or store energy from the solar power. The whole system is thus designed to operate with multiple operating modes. Compared to the system of single operating mode, the stability analysis and closed-loop design is much more difficult, as the control loops are usually coupled with each other and the design for stable operation of such system requires consideration of the stability conditions for all possible operating modes. To design the closed-loop, the commonly used small-signal analysis method based on averaged state-space is helpless here, and then the nonlinear analysis method with discrete-time mapping model is performed to evaluate the stability boundaries of the system. The parameters of the closed-loop are chosen in the stable region of the stability boundary diagrams. Moreover, a prototype is built and the experimental results are shown to verify the nonlinear analysis method in the design of closed-loop.
Abstract: The photovoltaic-battery hybrid power system is constructed with photovoltaic panels and a battery, which are connected to the load via a boost converter and a bidirectional buck/boost converter, respectively. Depending on the amount of available solar power, the photovoltaic panels may operate in a maximum power point tracking (MPPT) mode or off-M...
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Analysis of Series-Connected IGBTs Protection Method under Short Circuit II
Mei Guifang,
Xu Guancheng,
Lv Miao,
Lang Xuebin,
Dong Xiaoshuai,
Yang Xinran
Issue:
Volume 4, Issue 5, October 2016
Pages:
139-144
Received:
22 November 2016
Published:
24 November 2016
Abstract: The difference between single and series-connected insulated gate bipolar transistor (IGBTs) during short circuit II (SC II) is analyzed contrastively, and requirements for an improved protection have been advanced to solve the SC II problem of series-connected IGBTs. A new principle of short circuit protection based on the logic of SC II fault processing used by the main control unit was proposed, using an active voltage clamping circuit to balance the dynamic voltage during breakdown, using an RC circuit to balance the voltage during tail current stage, and a formula to estimate the absorption capacitance and the selection principle of static voltage balancing resistance was proposed. The parameters under the actual test condition was given, the short circuit test system of series-connected IGBTs established, and the experimental verification carried out under the actual conditions. The result shows that under a Vbus of 1400V (2.65kV maximum peak voltage for each IGBT), the new protection method can provide synchronization of protect operation and voltage balancing during turning-off process, and the unbalance of steady stage voltage is under 5%.
Abstract: The difference between single and series-connected insulated gate bipolar transistor (IGBTs) during short circuit II (SC II) is analyzed contrastively, and requirements for an improved protection have been advanced to solve the SC II problem of series-connected IGBTs. A new principle of short circuit protection based on the logic of SC II fault pro...
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