Power Distribution Method Research Articles

Unbalanced Power Allocation Method to the Research of the Influence of the Power System Trend

After the disturbance of the power system, all generators of the system will react the disturb and adjust the output. All unbalanced power in the traditional method of trend fully will be assumed by the balancing bus, obviously do not conform to the actual operation situation. Dynamic power flow calculation can effectively deal with this problem, the current calculation method of the unbalanced power distribution exist two kinds of thinking:based on moment of inertia of the generator and based on the frequency characteristic coefficient of the generator . Here, this paper state the two methods of distribution , through analysis and comparison ,use case simulation verify the influence of the different methods of distribution on the system steady trend.

Microgrid Development Using A Grid Tie Inverter

The use of renewable energy sources (RES), especially photovoltaic (PV), to meet the demand of electrical energy has beenn gettingn an greatn dealn ofn attentionn asn ann alternativen solutionn ton electricaln energyn deficitn problems.n RESn aren being appliedn inn powern systemsn inn an varietyn ofn configurationsn includingn microgridn systems.n Onen ofn then characteristicsn ofn a microgridn isn capabilityn ton supplyingn powern ton gridn whenn theren isn ann excessn powern ton supplyn localn load.n Thisn research examinesn then chancesn ofn savingn powern consumptionn fromn gridn usingn powern convertersn gridn tien invertern (GTI)n inn a microgrid configuration. The test is done by using a zero load and power distribution methods. Test results show grid tie GTIn capablen ofn supplyingn electricaln powern ton gridn upn ton 98%n ofn then inputn powern converter.n Inn then microgrid configuration power USAge from grid can be reduced up to 91%, which should be supplied from the grid to load.

INVESTIGATION OF CAPACITY GAINS IN MIMO CORRELATED RICIAN FADING CHANNELS SYSTEMS

This paper investigate the effect of Rician fading and correlation on the capacity and diversity of MIMO channels. The use of antenna arrays at both sides of the wireless communication link (MIMO systems) can increase channel capacity provided the propagation medium is rich scattering or Rayleigh fading and the antenna arrays at both sides are uncorrelated. However, the presence of line-of-sight (LOS) component and correlation of real world wireless channels may affect the system performance. Along with that we also investigate power distribution methods for higher capacity gains and effect of CSI at the transmitter on the capacity for range of SNR. Our investigation follows capacity gain as function of number of antennas and signal-to-noise (SNR) power ratio Block and frequency nonselective Rician fading channel is assumed, and the effect of Rician factor (L) and the correlation parameter (ρ) on the capacity and diversity gains of MIMO channels are found. Index.

Cooperative Control to Enhance the Frequency Stability of Islanded Microgrids with DFIG-SMES

The issue of frequency stability of microgrids under islanded operation mode and mode transfer has attracted particular attention recently. In this paper, a cooperative frequency control method, which consists of a microgrid central control (MGCC) and microgrid local control (MGLC), is proposed to achieve a seamless transfer from grid-connected to islanded mode, and hence increase the frequency stability of islanded microgrids during both primary and secondary frequency control. A power deficiency prediction and distribution method is proposed in MGCC to effectively distribute and utilize the power and loads, and accomplish the cooperative control of all microgrid units. With regards to MGLC, a Hopfield fuzzy neural network control (HFNNC) is applied to make the corresponding frequency control of DFIG-SMES more adaptive. Meanwhile a state of capacity (SOC) control is utilized in battery energy storage (BES) to extend battery life. Simulation results indicate that the proposed frequency control approach can maintain the frequency stability of islanded microgrids even in emergency conditions.

An Optimal Power Distribution on Decentralized Energy Networks with Battery Degradation Control

This paper proposes an optimal power distribution method on decentralized energy network with battery degradation control. Because the battery degradation is unavoidable phenomenon for the battery utilization, we solve the optimal power distribution problem by MIP formulation to keep the battery degradation minimum.

Determination of protection system requirements for DC unmanned aerial vehicle electrical power networks for enhanced capability and survivability

A growing number of designs of future unmanned aerial vehicle (UAV) applications utilise DC for the primary power distribution method. Such systems typically employ large numbers of power electronic converters as interfaces for novel loads and generators. The characteristic behaviour of these systems under electrical fault conditions, and in particular their natural response, can produce particularly demanding protection requirements. Although a number of protection methods for multi-terminal DC networks have been proposed in the literature, these are not universally applicable and will not meet the specific protection challenges associated with the aerospace domain. Through extensive analysis, this study seeks to determine the operating requirements of protection systems for compact DC networks proposed for future UAV applications, with particular emphasis on dealing with the issues of capacitive discharge in these compact networks. The capability of existing multi-terminal DC network protection methods and technologies are then assessed against these criteria in order to determine their suitability for UAV applications. Recommendations for best protection practice are proposed and key inhibiting research challenges are discussed.

Power Distribution in Propulsion System of Semiautonomous Underwater Vehicle

This paper presents methods of power distribution in propulsion system of a small torpedo-shape underwater vehicle maneuverable in three dimensions. It concentrates on finding an optimal thrust allocation among thrusters for demanded values of propulsive forces and moments. The proposed approach is directed towards obtain high propulsive efficiency necessary to realize required mission. Two described methods allow minimizing the propulsion system’s power consumption necessary to produce required thrusts.

Power distribution methods for MIMO‐OFDM systems and field experimentations

AbstractIn this paper, we propose several power allocation schemes for multi‐input multi‐output (MIMO) orthogonal frequency division multiplexing (OFDM) transmission based on the minimization of an approximated bit error rate (BER) expression, and we evaluate the different solutions via field trial experimentations. The methods illustrated in this paper, serve to allocate power among the different transmit antennas and the different subcarriers which compose the MIMO OFDM transmitted signal. Several solutions are available to perform power allocation. Frequency domain power allocation, spatial domain power allocation and combined spatial and frequency power allocation are evaluated. We first review and describe the analytical solution for each power allocation scheme and then evaluate the complexity in terms of both computational operations and BER performances. Simulation results show the performance in term of BER and link the advantage of each possibility of power distribution with the associated complexity. Copyright © 2009 John Wiley & Sons, Ltd.

<p>Potential Ambient Energy-Harvesting Sources and Techniques</p>

Ambient energy harvesting is also known as energy scavenging or power harvesting, and it is the process where energy is obtained from the environment. A variety of techniques are available for energy scavenging, including solar and wind powers, ocean waves, piezoelectricity, thermoelectricity, and physical motions. For example, some systems convert random motions, including ocean waves, into useful electrical energy that can be used by oceanographic monitoring wireless sensor nodes for autonomous surveillance. Ambient energy sources are classified as energy reservoirs, power distribution methods, or power-scavenging methods, which may enable portable or wireless systems to be completely battery independent and self sustaining. The students from different disciplines, such as industrial technology, construction, design and development and electronics, investigated the effectiveness of ambient energy as a source of power. After an extensive literature review, students summarized each potential ambient energy source and explained future energy-harvesting systems to generate or produce electrical energy as a support to conventional energy storage devices. This article investigates recent studies about potential ambient energy-harvesting sources and systems.

Power Distribution in Multi-thruster Propulsion System of Undersea Robotic Vehicle

The paper presents methods of power distribution in a multi-thruster propulsion system of an undersea robot. It concentrates on finding an optimal thrust allocation for desired values of propulsive forces and moments. The optimization is directed towards minimization of energy expenditures necessary to required control obtain. Special attention is paid to the unconstrained thrust allocation and techniques like the quadratic programming, the method of least squares and the method of matrix orthogonalization.

A Novel Power Distribution Scheme Combined with Adaptive Modulation Based on Subcarrier Grouping for OFDM Systems

In this paper, we propose to adapt both the modulation scheme and the transmit power in the frequency domain using a heuristic evaluation of the bit error rate (BER) for each subcarrier. The proposed method consists in ordering in terms of fading impact, grouping a certain number of subcarriers and performing local power adaptation in each subcarrier group. The subcarrier grouping is performed in order to equalize the average channel condition of each subcarrier group. Grouping and local power adaptation allow us to take advantage of the channel variations and to reduce the computational complexity of the proposed power distribution scheme, while avoiding the performance degradation due to the suboptimum power adaptation as much as possible. Compared to the conventional power distribution methods, the proposed scheme does not require any iterative process and the power adaptation is directly performed using an analytical formula. Simulations show a gain in terms of BER performance compared to equal power distribution and existing algorithms for power distribution. In addition, due to the subcarrier group specificity, the trade-off between the computational complexity and the performance can be controlled by adjusting the size of the subcarrier groups. Simulation results show significant improvement of BER performance compared to equal power allocation.

Guide to electrical power distribution systems

Written by a highly regarded power industry expert, this comprehensive manual covers in full detail all aspects of electric power distribution systems, both as they exist today and as they are evolving toward the future. A new chapter examines the impact of the emergence of cogeneration and distributed generation on the power distribution network. Topics include an overview of the process of electricity transmission and distribution, a thorough discussion of each component of the system – conductor supports, insulators and conductors, line equipment, substations, distribution circuits and more – as well as both overhead and underground construction considerations. Improvements in both materials and methods of power distribution are also explored, including the trend toward gradual replacement of heavier porcelain insulators with lighter polymer ones. The complex aspects of electric power distribution are explained in easy-to-understand, non-technical language.

Electric distribution and control for lighting systems

Higher illumination levels and new lighting sources make it necessary to re-examine possible methods of power distribution and control for lighting loads. As a result of the higher lighting load densities and versatile lighting sources, the designer must now exercise a considerable amount of engineering judgment in planning the distribution system. New design techniques make it possible to provide maximum convenience and reliability at minimum cost and with a minimum use of critical materials. The purpose of this paper is to discuss some of the requirements of the different lighting sources and analyze the modern trends in power distribution and control for lighting loads.

Modern Electric-Power-Distribution Ideas as Applied in a Large War Plant

It may be concluded, without reservation, that the application of load-center distribution principles as herein described was responsible for an amazing reduction in material investment, principally copper and steel, compared with that which would have been required by power-distribution methods employed only a short time ago. In the planning of this project, the greatest emphasis constantly was placed on conservation of materials. The use of compact, repetitively manufactured metal-clad, load-center unit substations do realize good economy in materials and man-hours, and at the same time incorporate simplicity and safety. Unusual features incorporated in this system, which in themselves are responsible for large savings in material, manhours, or both, include: 1. The application of forced-oil air-pressure cooling to the main incoming service transformers. 2. The use of overhead high-voltage feeder-cable troughs. 3. The use of spaced single-conductor low-voltage feeder design with moderate unit copper cross sections. 4. The use of 265-volt fluorescent lighting in combination with common load-center unit substations for serving power and light. (This feature alone accounts for a saving of five tons of copper and ten tons of steel compared with the most economical method of applying 120-volt fluorescent lighting. The secondary selective system design offers a well-balanced combination of simplicity and service reliability. The negotiation of the entire distribution system as a single unit proved highly beneficial in reducing the time of execution and insuring the best co-ordination between the several component portions.