System Loss Reduction Research Articles

GREY WOLF OPTIMIZER BASED OPTIMAL PLACEMENT OF MULTIPLE FACTS DEVICES IN THE TRANSMISSION SYSTEM UNDER DYNAMIC LOADING SYSTEM

The application of grey wolf optimization technique for multiple FACTS placement is presented in this paper for the reduction of total system losses and minimization of voltage deviation via optimal placement of Flexible AC Transmission System (FACTS) device. Grey wolf optimization (GWO) technique is inspired by social hierarchy and hunting behaviour of wolves and offers a right balance between exploration and exploitation during the search for global optimal. Series-shunt FACTS device; unified power flow controller (UPFC) is considered as a formidable device that can provides an alternative option for the flexible controllability and improvement of power transfer capability of a transmission lines. The analyses were conducted by increasing the number of UPFC in the network in order to evaluate the optimal number of FACTS devices that would give the least loss under maximum loading and contingency conditions. The efficacy of this proposed technique is demonstrated on 31-bus, 330 kV Nigeria National Grid (NNG) using MATLAB environment. The results show that optimal placement of FACTS device along with optimization technique provides a promising solution to the high power loss and voltage deviation bedevilling Nigeria National Grid.

A novel methodology for power loss allocation of both passive and active power distribution systems

Abstract This paper presents a new active power loss allocation (LA) scheme for fair allocation of losses among the end-user with due consideration to deregulation in power supply. In this deregulated environment, the developed technique assigns losses judiciously because it has simplified the difficulties lying with the division of cross-term power loss equation analytically without any assumptions and approximations. Further, it establishes a direct relationship between two end-voltages of a branch and its subsequent load currents, in terms of node-injected complex powers. This LA scheme assigns losses to the network participants with due consideration to their demands, power factors, and geographical locations in the network. Again, the strategy followed for remuneration of distributed generators (DGs) awards all benefits of network loss reduction (NLR) to the DG owners in terms of incentives/penalties after analyzing their actual impact towards system loss reduction. The effectiveness of the proposed method is not only investigated at different load levels but also with various types of DG power injection using a 33-bus radial distribution network (RDN) with/without DGs. The comparison results obtained signify the novelty of the present technique in contrast to other discussed established methods.

Optimum Topology of Power Distribution Networks Using Sunflower Optimizer for Loss Reduction.(Dept.E)

The network reconfiguration can aid in loss reduction in distribution systems. A neoteric optimization method, Sunflower Optimizer (SFO), is suggested for addressing the reconfiguration of power distribution networks case. The main problem is to determine the network's optimal topology, which satisfies the objective function by considering the problem constraints. The fitness function is formulated to achieve the maximum percentage of active power loss decrease. To obtain the load flow solution, an efficient approach is applied called Backward/forward sweep. Besides, an improved graph theory is developed to address the configuration variations problem. The suggested optimization approach is executed on three power distribution networks: IEEE 33, 69, and 119 bus networks. The efficiency of the suggested SFO is verified by evaluating its operational characteristics. The obtained test results show that the percentage of active power loss reduction is maximized to 31%, 56%, and 33% for the IEEE 33, 69, and 119 bus networks, respectively. Finally, the introduced SFO approach's superiority is also confirmed by measuring its outcomes with other approaches..

Reduction of distribution system losses using solar energy cooperativity by home user

Solar energy cooperatives have been gaining importance day by day in renewable energy resources. However, selection of the establishment points of renewable energy cooperatives in the distribution system is a technical problem. In this study, the effects of regional solar power system installations on the reduction of power losses in the distribution system and the expansion of solar energy cooperatives by home user were examined. In this way, it is aimed to reduce business setup costs by using a decentralized cooperative network for micro grids. The new model aims to replace the most appropriate placement of solar energy cooperatives in the distribution system. The annual electricity generation value obtained from solar power system was compared with the transformer-based annual consumption values. Then the number of domestic users that would benefit from solar power system for each region was determined. As a result, details and result of the proposed model presented.

Research on MTPA Control Strategy of Permanent Magnet Synchronous Motor Based on Fast SVPWM Algorithm

In recent years, the poor endurance of electric vehicles has been one of the main problems that have limited the development of new energy vehicles. Improving system efficiency and reducing system losses are currently one of the main methods to improve endurance. A fast SVPWM (Space Vector Pulse Width Modulation Technology) algorithm is used to improve the traditional SVPWM judgment, simplifying the complicated coordinate transformation and trigonometric function calculation of the traditional SVPWM technology judgment. Then it is applied to MTPA (Maximum Torque Per Ampere) control for Simulink model simulation to verify the effect. The experiment proves that the MTPA control under the improved SVPWM algorithm has higher response speed and stability than the traditional id = 0 control. The size of the stator current is about 1-2A smaller than id = 0 control, which achieves better MTPA control.

Loss Reduction in Distribution System using Best Practices

This paper talks about the implementation of the best practices to reduce the losses related to Transmission and Distribution (T&D) system. Distribution system is one of the major areas where the distribution companies (DisComs) face huge losses, therefore, reduction of T&D losses may bring profit to the DisComs. In this work, various technical losses are identified and tackled accordingly. This paper also discusses the measures to be taken to reduce the losses and hence increase the overall efficiency of the network.

Beaconless PAT and adaptive beam control using variable focus lens for free-space optical communication systems

Free-space optical communications (FSOCs) have recently emerged as a promising solution for various communication scenarios. However, the pointing, acquisition, and tracking (PAT) is a technically challenging issue, especially in airborne FSOC systems. In this paper, we present an adaptive beam control technique combined with beaconless PAT using a variable focus lens. By using the lens whose focal length can be tuned electrically, we facilitate the coarse PAT by enlarging the beam size and also mitigate the adverse effects of pointing errors by adjusting the beam divergence angle adaptively to the link conditions. The major benefit of the proposed scheme is that the beam control can be implemented in a simple and compact manner, without relying on mechanical movements. We carry out a proof-of-concept experimental demonstration of the proposed scheme for a 10-Gb/s free-space optical link over 104 m. The demonstration shows that the probability of PAT success can be improved considerably by using the proposed scheme. It also shows that the proposed scheme could result in a system loss reduction of 6.4 dB and improve the tolerance to pointing errors up to 500 μrad for a target bit-error ratio of 10−3. The response time of the lens is measured to be <211 ms. We confirm experimentally that the receiver size and the amount of pointing error determine the optimum beam size at the receiver.

Optimal allocation of multiple DGS in RDS using PSO and its impact on system reliability

This article presents the distributed generator (DG) integration in a radial distribution system (RDS). The DG penetration changes the single power source to multiple power sources and bidirectional load flow which enhances the system reliability and reduces system power losses. The particle swarm optimization and gravitational search algorithm are implemented for the optimal siting and sizing of one and three DG units in the RDS to examine its impact on system reliability and loss reduction. The types of DGs considered are Type I (injects real power) and Type IV (injects reactive and real power). The constant power is the chosen load model. The reliability indices taken for the analysis of system reliability are Average Energy Not Supplied, Total Energy Not Supplied and Average System Interruption Duration Index. The efficacy of the proposed method is validated on 33-bus in the presence of single and multiple DGs. The significant decrease in system power losses with the upgraded bus voltage profile, system reliability and remarkable annual loss saving is analyzed for Type IV DG over Type I DG. The results determined are compared to other meta-heuristic approaches as well as analytical techniques to demonstrate the superiority of the proposed methodology. The results are also statistically verified.

An Optimal Phase Arrangement of Distribution Transformers under Risk Assessment

This paper presents a phase arrangement procedure for distribution transformers to improve system unbalance and voltage profile of distribution systems, while considering the location and uncertainties of the wind turbine (WT) and photovoltaics (PV). Based on historical data, the Monte Carlo method is used to calculate the power generation value-at-risk (VAR) of WTs/PVs installed under a given level of confidence. The main target of this paper is to reduce the line loss and unbalance factor during 24-hour intervals. Assessing the various confidence levels of risk, a feasible particle swarm optimization (FPSO) is proposed to solve the optimal location of WTs/PVs installed and transformer load arrangement. A three-phase power flow with equivalent current injection (ECI) is analyzed to demonstrate the operating efficiency of the FPSO in a Taipower feeder. Simulation results will support the planner in the proper location of WTs/PVs installed to reduce system losses and maintain the voltage profile. They can also provide more risk information for handing uncertainties when the renewable energy is connected to the distribution system.

Evaluation of Distributed Generation Impact on Reliability of a Distribution System using DIgSILENT PowerFactory

As an effective supplement to the centralized fossil fuel based traditional generation, Distributed Generation (DG) has become an effective alternative choice and has been rapidly increasing since past few years due to growing demand for electricity and the new policies of governing bodies for usage of green energy. In overall power system, distribution systems are more vulnerable to faults and reliability aspects of such systems becomes an important issue. With higher penetration of DG into the distribution network, it will be necessary to study the impact of such generation on the various aspects of distribution system. Thus, increase in rate of penetration DGs into the distribution system on one side and increased faults in distribution network on another side, will make the study of impact of DG integration on distribution system reliability an interesting topic of research. The present work focuses on evaluation of impacts of integration of such DGs on reliability of local distribution network, typically in an urban scenario By using the simulation method using DIgSILENT PowerFactory software, the impacts of integration of DG in terms of enhancement in distribution system reliability indices and reduction in system losses for different scenarios are studied and presented in this paper. Based on the simulation results obtained and after analysis of the distribution system, overall results are summarized by focusing on the installation of suitable capacity of DG and the location of DG which are important factors affecting the system losses and system reliability indices.

Optimized Two-Time Scale Robust Dispatching Method for the Multi-Terminal Soft Open Point in Unbalanced Active Distribution Networks

To alleviate the impact of output uncertainty of renewable energy sources (RESs) in unbalanced active distribution networks (ADNs), this paper proposed a two-time scale robust optimization method for the multi-terminal soft open point (SOP). In the long-term scale, the operation points of the SOP were optimized by semidefinite programming (SDP) model to minimize system loss and mitigate voltage unbalance. An improved iterative cutting plane (ICP) method was proposed to strengthen the exactness of the SDP rank-one relaxation. In the short-term scale, V 2- P and V 2- Q droop control mode was implemented in the SOP to better respond to the output uncertainty of RESs. Then a slope robust optimization model was established based on long-term operation points and short-term forecast data to improve system robust security. To coordinate these two time scales, a co-optimization re-dispatch strategy was proposed in the short-term model so that the robust safety margin could be further expanded in extreme conditions. Case studies show that the proposed method can fully utilize the flexible power flow regulation ability of the multi-terminal SOP to reduce system loss, mitigate voltage unbalance and guarantee system robust security in the presence of RES output uncertainty.

RETRACTED: Designing a miniaturized photoacoustic sensor for detecting hydrogen gas

In this paper, photoacoustic spectroscopy method is used for hydrogen gas detection. In order to improve the performance of the sensor, we have used a miniaturized dumbbell-shaped cell containing two buffer volumes and a resonator. The coupled photoacoustic equations have been solved in gaseous environment using finite-element-method and by corresponding validation. The impacts of various effective parameters such as frequency response, quality factor, acoustic pressure and heat have been analyzed. Frequency analysis in the hydrogen gas medium leads to the first natural frequency of the sensor at 88.563 kHz which has 65 kHz difference with the second natural frequency. By studying the behavior of the resonance frequencies of the proposed system, the optimum location for the sensor positioning of the designed system has been investigated for different gases and the results show that the designed photoacoustic sensor has the fingerprint feature for detecting hydrogen gas. Moreover, the results of the cell filled by hydrogen gas have been compared to those obtained from other gases such as propane, nitrogen and carbon dioxide. The performance of the system is also evaluated for volatile organic compounds (VOCs) and nitrogen dioxide (NO2). The analysis of the proposed miniature system shows a significant improvement in the quality factor as well as the reduction in system losses.

Coordination of PV Inverters and Voltage Regulators Considering Generation Correlation and Voltage Quality Constraints for Loss Minimization

Distributed generation sources (DGs) are widely considered as important sources of power generation in distribution systems during the last few decades. Despite the substantial benefits of DGs, increasing the penetration level of the DGs can cause dramatic voltage magnitude fluctuations. Coordination of the use of dynamic reactive power sources such as photovoltaic (PV) inverters and voltage control equipment can mitigate rapid voltage magnitude fluctuations. A coordinated volt-var control method is proposed herein to achieve the optimal expected performance (e.g., system losses) while considering the spatial correlation among PV source powers and constraining the variability of voltage magnitudes throughout the distribution network within permissible ranges. The proposed strategy formulates chance constraints on the voltage magnitude and considers the uncertainty of PV power injections over the interval of interest to maintain voltage magnitudes within acceptable limits. The proposed method has been tested on the IEEE 123-node radial distribution system for validation. Moreover, the simulation results demonstrate that the proposed method can effectively mitigate the fast voltage magnitude deviations with an acceptable reduction in system losses in the presence of intermittent renewable resources.

Enhancing energy utilization efficiency of Pakistani system considering FACTS devices and distributed generation: Feasibility study

In recent years, voltage stability issues have become a serious concern with regard to the safety of electrical systems, these issues are more evident and have wider consequences in vertical networks with an insufficient reactive power reserve. Pakistan is currently suffering from the worst energy crisis in its history. Owing to an increase in energy demand, the current transmission system is becoming increasingly inadequate. It has thus become necessary to reduce losses and enhance the system voltage profile for more efficient energy utilization. In this study, the main emphasis is on assessing the feasibility of using flexible AC transmission system devices and distributed generation to compensate power failures on the power lines of the Pakistani power transmission system. The load flow and contingency analyses are performed on a 132 kV transmission system that feeds power to the Quetta electric supply company. The region of Baluchistan is studied to evaluate the effectiveness of the proposed method. The system is simulated using NEPLAN, which accurately models the details of all system elements and the optimal power flow. The simulation results indicate that the proposed method helps reduce system losses, voltage deviation, and power flow congestion, with all system constraints within permissible limits.

A branch oriented active power loss allocation method for radial distribution networks with distributed generators

The penetration of distributed generation (DG) units in the radial distribution network (RDN) introduces complexity in active power loss allocation (LA) as it leads to reverse current in the network. This current makes power system bidirectional and brings difficulties in the decomposition of cross-terms of power loss equation. To overcome such complications, this paper proposes a new branch oriented LA technique which eliminates the impact of mutual-term mathematically from loss formulation without any assumptions and approximations. It establishes a direct relationship between the subsequent load currents of a branch and its two end voltages in terms of the complex power available at its load ends. The proposed LA scheme is found to be fair as regard to the topology of the RDN. Further, the implementation of DGs may increase/decrease power loss of a system. In order to provide the exact amount of loss reduction benefit to the DG owners (DGOs), a new DG remuneration strategy is developed in this paper which assigns either rewards/penalties to the DGOs after analysing their actual impact towards system loss reduction. The effectiveness of the proposed LA method is investigated against various established LA techniques using two different test systems i.e., 17-bus and 33-bus RDNs.

Optimal Distributed Energy Resources Allocation for Enriching Reliability and Economic Benefits Using Sine-Cosine Algorithm

This paper presents an optimization algorithm called sine-cosine algorithm (SCA) for optimal distributed energy resources (DERs) allocation in various configurations of radial distribution networks. This study is demonstrated in two statuses to find the optimal locations and sizes of DERs to be installed on the distribution system. First status; the most candidate locations for connecting DERs are suggested by using the loss sensitivity factor theory and the proposed SCA is applied to select the optimal capacities of DERs. Second status; the SCA is used to determine both the optimal locations and sizes of DERs. The positive impact of DERs on distribution systems reliability has been investigated in addition to the system power losses and bus voltages. The fitness function is to maximize the savings produced by not only power losses reduction but also reliability enhancement. The proposed algorithm is applied to IEEE 33 and 69-bus radial distribution networks with installing different number of DERs. The simulation results using Matlab programming environment show that the proposed methodology is viable, supporting reliability as well as fulfilling the conventional objectives such as cost minimization, voltage profile improvement, system losses reduction. A comparison between SCA and other methods is introduced to verify the superiority of SCA where SCA fulfils the maximum saving and maximum reduction of power losses equals to 61.3% and 69.2% for IEEE 33-bus and 69-bus networks, respectively.

A new methodology for optimal location and sizing of battery energy storage system in distribution networks for loss reduction

Abstract In this study, a new methodology has been proposed for optimal allocation and optimal sizing of a lithium-ion battery energy storage system (BESS). The main purpose is to minimize the total loss reduction in the distribution system. The optimization process is applied using a newly developed type of Cayote Optimization Algorithm (COA). The proposed technique includes two different approaches. In the first approach, the optimization for allocation and the sizing are performed one by one and in the second approach, the optimization has been done simultaneously. To analyze the proposed system, four different scenarios have been analyzed which include different conditions without/with PVs and also using single/two BESS. The results showed that using two BESS can reduce the total error of the distribution system. the results also showed that using PVs can also decrease the total losses. Finally, the proposed approach based on ICOA is compared with Firefly Algorithm (FA), Whale Optimization Algorithm (WOA), and Particle Swarm Optimization (PSO) to show the proposed method's prominence efficiency.

Optimal reactive power dispatch using particle swarm optimization algorithm for Yangon distribution network

Optimal Reactive Power Dispatch (ORPD) is very efficient to optimize the control variables like as generator voltages, transformer tap setting and values of reactive power injection for loss reduction in power system. ORPD is the one of the complexity of optimization problems including with equality and inequality constraints of power systems. Many research papers have developed in ORPD applied to the IEEE test systems with various intelligent methods for the loss reduction. In this paper, the test system is carried out on Yangon Distribution Network (YDN) composed of different voltage level such as 230 kV, 66 kV and 33 kV, and supplied by various types of generation sources. Thus, it is very high in losses and difficult to find out the control variables of ORPD in YDN. The main objective is to reduce the both active and reactive power losses in YDN. Particle Swarm Optimization (PSO) method implemented in ORPD problem of YDN is very applicable and effective to obtain the minimum losses while all the bus voltage profile is acceptable in voltage constraints. The obtained results from ORPD using PSO algorithm could enhance YDN efficiently.

A hybrid algorithm based optimal placement of DG units for loss reduction in the distribution system

Distributed generation (DG) has been utilized in some electric power networks. Power loss reduction, environmental friendliness, voltage improvement, postponement of system upgrading, and increasing reliability are some advantages of DG-unit application This paper uses a hybrid technique to optimize the position and size of DG units to reduce losses in the distribution system. The hybrid technique is the joined execution of both the Grasshopper Optimization Algorithm (GOA) and Cuckoo Search (CS) technique. Here, the GOA optimization behavior is upgraded by utilizing the CS technique. Here, the perfect position of the DG unit is settled with respect to the power loss, line power flow and voltage profile using the proposed system. For improving the dynamic execution, the limit of DG is directed by the proposed technique with respect to the cost work. The motivation behind the proposed system is to produce optimal capacity to lessen the aggregate power loss and enhance the voltage profiles of power distribution networks. The proposed hybrid technique is executed in MATLAB/Simulink working platform and the dynamic dependability execution is tested and considered with IEEE 33-bus distribution networks and IEEE 69-bus system. The stability by diminishing loss of the distribution system is investigated by executed different load state of the system. The execution of the proposed system is analyzed and compared with different existing techniques.

Loss Reduction In Power System Using Evolutionary Algorithm

Loss reduction in power system using algorithm is one of the important tasks in the operation and control of power system. This paper presents a well-organized and consistent evolutionary-based approach to solve real power problem. The proposed method employs evolutionary algorithm for optimal settings of reactive power dispatch control variables. The proposed method has been tested on the IEEE 30-bus test system with different objectives that reflect power losses minimization, fuel cost minimization. After observing simulation results, it is expressed by differential evolution/ evolutionary approach, which has been adjusted. In such a way it will give better convergent time than other optimization methods.