by Ignatius K. Okakwu, Emmanuel A. Ogujor and Patrick A. Oriaifo
Original Research
The Nigerian 330kV grid network is characterized with major problems like voltage instability (voltage profile violation), long transmission lines, nature of transmission lines and high power losses which affect power generation and distribution systems. This paper considered the load-flow study of the Nigerian 330-kV consisting of 32 buses, 11 generating stations and 36 transmission lines. Newton-Raphson iteration technique was used to carry out the analysis because of its fast convergence nature as compared to other iterative techniques. The data used for the study is obtained from Power Holding Company of Nigeria (PHCN). MATLAB/SIMULINK software was used to carry out the simulations. The results obtained shows that some of the bus voltages lie outside the prescribed limit of 0.95-1.05 pu (313.5 – 346.5kV). These buses include buses 16 (Kano 0.8721pu), 17(Kaduna, 0.9046pu), 18(Jos, 0.8580pu), 19(Gombe 0.8735pu) and 21(Katampe, 0.9167pu). The total active power loss is 268.622MW and that of reactive power loss is 2247.42Mvar. It is therefore inferred from the results obtained that the existing Nigerian 330-kV grid network is fraught with high line losses that require compensation using reactive power supports such as Flexible Alternating Current Transmission Systems (FACTS) devices, for effective line utilization.
American Journal of Electrical and Electronic Engineering. 2017, 5(4), 159-165. DOI: 10.12691/ajeee-5-4-6
Pub. Date: August 02, 2017
13032 Views3526 Downloads
by Poolo I.J
Original Research
The demand side management has gained considerable prospects and encounters due to the coming in of the Smart Grid. It is also anticipated that the advanced metering infrastructure will enhance the demand side management establishments. This paper discusses the proposed demand side management archetypal that relies on the advanced metering infrastructure for the smart grid. The archetypal has the following components; a collaborative or two-way communication grid, a metering infrastructure and submission software on the user’s end and regulator side correspondingly. We present and discuss the inter-associations for the various minor components that make up the archetypal. In the proposed work, the terminal consumer circulated power resources are taken into account. This archetypal is meant to improve the communication between the power end user and the supply side. It is assumed that it will enhance power distribution and serve as a bench mark to the smart distribution system load management.
American Journal of Electrical and Electronic Engineering. 2017, 5(4), 152-158. DOI: 10.12691/ajeee-5-4-5
Pub. Date: July 18, 2017
10452 Views1864 Downloads
by Yixi Chen, Rong Ju, Jie Xu, Gang Ma, Huaiyi Chen and Guchao Xu
Original Research
Resonant grounding system has been widely applied in low-voltage power systems all over the world. For the single-phase ground fault feeder-selection of resonant grounding system, the amplitude/phase comparison method of zero-sequence current which is used in traditional fault feeder-selection is not suitable to be used, due to the compensation action of arc suppression coil. In this paper, the electrical quantity changes after the single-phase ground fault of small current grounded system are analyzed firstly, therefore the reason why the amplitude/phase comparison method of zero-sequence current is not suitable to be used in resonant grounding system can be obtained. After that, based on zero-sequence current’s multi-state components (transient component and steady component), a new fault feeder-selection method using double criteria is proposed, which not only can be applied in the single-phase ground fault of resonant grounding system but also has high reliability. At last, simulations based on MATLAB/Simulink are conducted to verify the validity of the method proposed in this paper.
American Journal of Electrical and Electronic Engineering. 2017, 5(4), 144-151. DOI: 10.12691/ajeee-5-4-4
Pub. Date: July 17, 2017
17852 Views2967 Downloads3 Likes
by Doaa E. El. Matary, Esam A. A. Hagras and Hala Mansour Abdel-Kader
Original Research
For a multiuser Ultra Wide Band (UWB) system, the performance is mainly limited by inherent noise and interferences such as Multiple Access Interference (MAI) and Inter Symbol Interference (ISI) which are poorly approximated by a Gaussian distribution because of their impulsive nature. A combination between Orthogonal Frequency Division Multiplexing (OFDM) and Interleave Division Multiple Access (IDMA) has been considered as an efficient technique due to its bandwidth efficiency, and robustness against MAI and ISI. Moreover, OFDM-IDMA technique has the ability to allow frequency diversity and performance improvement with the help of efficient FEC coding technique such as Low Density Parity Check (LDPC) code. Therefore, this paper addresses the performance of LDPC-coded-IDMA-based OFDM-UWB communication system under Gaussian and non-Gaussian noisy channels. Three different models as Symmetric Alpha Stable (SS), Laplacian model and Gaussian Mixture Model (GMM), have been introduced for approximating the non-Gaussian noise which are more realistic for UWB system. Simulation results show that LDPC-coded OFDM-IDMA system is robust against noise and interferences in UWB indoor environment, and achieves good performance under Cauchy (SαS) model rather than other non-Gaussian models with simple Chip-By-Chip (CBC) iterative receiver. Furthermore, the proposed system gains a significant performance improvement compared with the un-coded OFDM-IDMA-UWB system under the studied noise models.
American Journal of Electrical and Electronic Engineering. 2017, 5(4), 136-143. DOI: 10.12691/ajeee-5-4-3
Pub. Date: July 17, 2017
13716 Views2503 Downloads
by Salaheddin Odeh, Tarek Rishmawi and Rafat Al-Hawash
Original Research
This paper proposes the hardware and software implementation of the system required to establish a low-cost educational remotely controlled solar energy laboratory. The system consists of two main parts, a Solar Energy System and a Remotely Controlled Laboratory. The Solar Energy System is a Photovoltaic system, which consists of multiple photovoltaic cells that convert solar radiation (sunlight) or normal lights into usable direct current (DC) electricity, and then it either charges a backup battery or uses an inverter circuit that changes direct current (DC) to alternating current (AC). The other part of the system is a Remotely Controlled Laboratory, aimed at enabling students to control solar energy experiments remotely.
American Journal of Electrical and Electronic Engineering. 2017, 5(4), 126-135. DOI: 10.12691/ajeee-5-4-2
Pub. Date: July 10, 2017
16601 Views2350 Downloads4 Likes
by Emmanuel U. Oleka, Evelyn R. Sowells and Gary L. Lebby
Original Research
Synchrophasor technology is receiving a global acceptance for electric power grid Wide Area Measurement System, (WAMS), an important function in a smart power transmission grid. A critical challenge in the synchrophasor technology deployment is the optimal choice of Phasor Measurement Unit (PMU) locations on the power grid. Researchers have proposed several techniques and algorithms in this respect. This work evaluated some of the major techniques and established that the available techniques and the factors they considered are not sufficient for a real-life optimal PMU placement (OPP). It also pointed to a method that could be applied to achieve a practical and robust solution for effective PMU placement for synchrophasor applications in a real-life electric power grid. It, therefore, calls for a shift in paradigm in the studies for the optimal PMU placement locations.
American Journal of Electrical and Electronic Engineering. 2017, 5(4), 120-125. DOI: 10.12691/ajeee-5-4-1
Pub. Date: July 03, 2017
15577 Views2675 Downloads