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Impact of Photovoltaic Tied to Electrical Grid System On Power Quality
Salah Kamal EL-Sayed,
Ehab Issa Okasha
Issue:
Volume 5, Issue 2, April 2017
Pages:
23-32
Received:
8 March 2017
Accepted:
17 March 2017
Published:
4 April 2017
Abstract: The High Penetration of PV power into the existing electricity grid needs more study and analysis to enable safe operation. One of the major concerns is the impact of PV system on grid power quality .Poor power quality could cause disturbance and financial losses due to the use of power inverters. Harmonic distortion is a serious power quality problem that reduces power quality and consequently causes a number of problems to consumer and network. This Paper proposes a new strategy for power quality improvement in a three-phase grid connected PV Inverter with central and string configuration and controlling on them using Sinusoidal pulse width modulation and space vector modulation methods with LCL Filter .This paper investigates PV Inverter configuration and impact of them on PV Plant Performance and harmonics that produced by PV inverter. The design, modeling, and analysis of a grid-tied PV system were performed in the PSCAD software simulation environment. The simulations of Harmonic Distortion (Total Demand Distortion & Total Harmonic Distortion) were applied at Point of Coming Coupling and the results obtained were compared with the limits specified by IEEE STD 519-1992 standards.
Abstract: The High Penetration of PV power into the existing electricity grid needs more study and analysis to enable safe operation. One of the major concerns is the impact of PV system on grid power quality .Poor power quality could cause disturbance and financial losses due to the use of power inverters. Harmonic distortion is a serious power quality prob...
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A New Method of Radar Signal Feature Parameter Assessment
Cheng Bolin,
Xu Jing,
Tang Yuwen
Issue:
Volume 5, Issue 2, April 2017
Pages:
33-37
Received:
5 April 2017
Published:
6 April 2017
Abstract: Aimed at the problem of radar signal feature parameter assessment in the process of sorting, a multi-index joint assessing method is proposed. This method uses complexity, separability and stability to assess the performance of feature parameters sorting. It overcomes the defects of traditional ways that cannot make an overall and scientific assessment by only using a single index. Meanwhile, it can get the optimal comprehensive score value under different application requirements. Its validity and good engineering utilization performance is proved by computer simulation.
Abstract: Aimed at the problem of radar signal feature parameter assessment in the process of sorting, a multi-index joint assessing method is proposed. This method uses complexity, separability and stability to assess the performance of feature parameters sorting. It overcomes the defects of traditional ways that cannot make an overall and scientific assess...
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Design of Coplanar Dipole Antenna with Inverted-H Slot for 0.9/1.575/2.0/2.4/2.45/5.0 GHz Applications
Issue:
Volume 5, Issue 2, April 2017
Pages:
38-47
Received:
5 April 2017
Published:
6 April 2017
Abstract: A coplanar symmetric dipole slot antenna with inverted-H slot is proposed for 0.9/1.575/2.0/2.4/2.45/5.0 GHz wireless communication applications. The inverted-H slot is etched on the metallic layer of a single sided printed circuit board to form the coplanar dipole slot antenna. The dimensions of inverted-H slot are changed to design and fabricate the antenna which can be operated at 0.9/1.575/2.0/2.4/2.45/5.0 GHz successfully. We use IE3D software to design this dipole slot antenna and choose the better parameters to manufacture the proposed antenna. The influences of slot dimension parameters of the proposed antenna on resonant frequency, input reflection coefficient expressed in decibel and impedance bandwidth are described. The proposed antenna with the volume of 123mm×31mm×1.6mm has been fabricated. The measured result shows that the proposed antenna can be successfully operated at 0.9/1.575/2.0/2.4/2.45/5.0 GHz.
Abstract: A coplanar symmetric dipole slot antenna with inverted-H slot is proposed for 0.9/1.575/2.0/2.4/2.45/5.0 GHz wireless communication applications. The inverted-H slot is etched on the metallic layer of a single sided printed circuit board to form the coplanar dipole slot antenna. The dimensions of inverted-H slot are changed to design and fabricate ...
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A Novel Sorting Method Based on Auto-correlation Function of Coherent Radar Signal
Wei Qing-yun,
Chen Bei,
Wang Jing,
Han Jun,
Tang Yu-wen
Issue:
Volume 5, Issue 2, April 2017
Pages:
48-52
Received:
5 April 2017
Published:
6 April 2017
Abstract: In order to solve the increasing-batch problem in signal sorting, a novel sorting method based on auto-correlation function of coherent radar signal is proposed. By using the instantaneous auto-correlation function of coherent signal, the discrimination model of ratio of peak values was built and applied in sorting simulation. Simulation results show that the proposed approach can solve the Increasing-batch problem for CW, LFM, NLFM one sorting when the signal-to-noise rate (SNR) above 5dB. The validity of the approach is demonstrated by experimental results.
Abstract: In order to solve the increasing-batch problem in signal sorting, a novel sorting method based on auto-correlation function of coherent radar signal is proposed. By using the instantaneous auto-correlation function of coherent signal, the discrimination model of ratio of peak values was built and applied in sorting simulation. Simulation results sh...
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Control Strategy for Distributed Integration of Photovoltaic and Energy Storage and Wind Power Systems in DC Micro-Grid
Issue:
Volume 5, Issue 2, April 2017
Pages:
53-62
Received:
3 March 2017
Accepted:
16 March 2017
Published:
7 April 2017
Abstract: Small DC networks to communicate effectively with a variety of output sources such as photovoltaic systems and wind energy storage systems,. If in addition the system DC power is fed over the need to transform and rectify AC network resources compared with a small decrease. Use most of the renewable energy the different factors fine network operates independently suggestions have been. When the system is network -independent, and the exploitation of natural and production of active power by a converter AC balance will be funded constant DC voltage is guaranteed Successful performance of the system in different positions by a coordinated strategy on energy storage systems and photovoltaic systems and wind energy will be discussed And about time management including load and battery state is considering proposals have been Differences by network performance monitoring method is specified MATLAB / SIMULINK, simulation proved strong on performance and determining the status of various systems and control function is proposed.
Abstract: Small DC networks to communicate effectively with a variety of output sources such as photovoltaic systems and wind energy storage systems,. If in addition the system DC power is fed over the need to transform and rectify AC network resources compared with a small decrease. Use most of the renewable energy the different factors fine network operate...
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Robust Detection Method of Arrival Time Difference Under Minimum Maximum Entropy Criterion
Wenhong Liu,
Junhao Li,
Niansheng Chen,
Guangyu Fan
Issue:
Volume 5, Issue 2, April 2017
Pages:
63-67
Received:
6 February 2017
Accepted:
24 March 2017
Published:
10 April 2017
Abstract: Accurate measurement of arrival time difference is one of the key technologies in many areas, such as the global positioning system. Due to the effects of environmental noises around receiver, the classic methods under least mean-square error rule are the lack of robustness. In this paper, a robust method of the time difference detection is addressed based on the minimum maximum entropy, referred to MMEATD. The maximum entropy function used in this method is a smooth approximation of the L1 norm. It has robustness to large outliers, but also is differentiable. Under the minimum maximum entropy criterion, the adaptive filter weight vector will be convergence, and its peak position indicates the arrival time difference. The computer simulation experiments show the estimation performance of this algorithm under different signal and noise ratio or different impulsive noise intension. Meanwhile, its estimation performance is compared with minimum mean square error algorithm. Results show that the proposed method has a good robustness under the impulsive noise environment.
Abstract: Accurate measurement of arrival time difference is one of the key technologies in many areas, such as the global positioning system. Due to the effects of environmental noises around receiver, the classic methods under least mean-square error rule are the lack of robustness. In this paper, a robust method of the time difference detection is address...
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Improved Particle Swarm Optimization with Controllable Velocity-Updating Mode
Jiao Weidong,
Huang Zhijing,
Yan Gongbiao
Issue:
Volume 5, Issue 2, April 2017
Pages:
68-73
Received:
11 April 2017
Published:
12 April 2017
Abstract: At the late evolution stage of the basic particle swarm optimization (BPSO), convergence process starts to slow down and the best fitness particle fluctuates around the globally-optimal solution, which may give rise to decrease on convergence precision of the BPSO. Therefore, an improved algorithm for particle swarm optimization was proposed. The modified version of PSO uses a controllable velocity-updating mode to control velocity of evolved particles, which is expected to be useful for tuning the search for the globally-optimal solution. Optimization examples showed that the improved PSO is superior to the BPSO, on not only convergence precision but also computation expense.
Abstract: At the late evolution stage of the basic particle swarm optimization (BPSO), convergence process starts to slow down and the best fitness particle fluctuates around the globally-optimal solution, which may give rise to decrease on convergence precision of the BPSO. Therefore, an improved algorithm for particle swarm optimization was proposed. The m...
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On the Determination of Levelized Cost of Electricity of Wind Energy in the Coastal Areas of Bangladesh
Fahmida Azmi,
M. Mofazzal Hossain
Issue:
Volume 5, Issue 2, April 2017
Pages:
74-79
Received:
19 February 2017
Accepted:
1 March 2017
Published:
13 April 2017
Abstract: Sustainable energy supply is the key to industrial, social and economic developments of any society. At the same time environment friendly sustainable energy supply is a burning issue nowadays. Among other renewable energy sources, due to geographical location, wind energy harvesting is more prospective in Bangladesh, especially in the coastal area of Bangladesh. In this work we studied the feasibility of harvesting wind energy in the coastal area of Bangladesh through the calculation of levelized cost of electricity (LCOE) at seven different locations. It is found that among seven locations the LCOE is approximately 5 BDT/kWh at Kuakata and St. Martin. We also investigated the effects of blade diameter and tower height on LCOE. It is found that the minimum LCOE may be achieved using blade diameter of 21.5 m and tower height has insignificant effects on the LCOE of wind energy for the coastal area of Bangladesh.
Abstract: Sustainable energy supply is the key to industrial, social and economic developments of any society. At the same time environment friendly sustainable energy supply is a burning issue nowadays. Among other renewable energy sources, due to geographical location, wind energy harvesting is more prospective in Bangladesh, especially in the coastal area...
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A Non-interactive Deniable Authentication Scheme in the Standard Model
Issue:
Volume 5, Issue 2, April 2017
Pages:
80-85
Received:
21 April 2017
Published:
21 April 2017
Abstract: Deniable authentication protocols enable a sender to authenticate a message to a receiver such that the receiver is unable to prove the identity of the sender to a third party. In contrast to interactive schemes, non-interactive deniable authentication schemes improve communication efficiency. Currently, several non-interactive deniable authentication schemes have been proposed with provable security in the random oracle model. In this paper, we study the problem of constructing non-interactive deniable authentication scheme secure in the standard model without bilinear groups. An efficient non-interactive deniable authentication scheme is presented by combining the Diffie-Hellman key exchange protocol with authenticated encryption schemes. We prove the security of our scheme by sequences of games and show that the computational cost of our construction can be dramatically reduced by applying pre-computation technique.
Abstract: Deniable authentication protocols enable a sender to authenticate a message to a receiver such that the receiver is unable to prove the identity of the sender to a third party. In contrast to interactive schemes, non-interactive deniable authentication schemes improve communication efficiency. Currently, several non-interactive deniable authenticat...
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