Fuzzy-GA based algorithm for optimal placement and sizing of distribution static compensator (DSTATCOM) for loss reduction of distribution network considering reconfiguration

This work presents a fuzzy based methodology for distribution system feeder reconfiguration considering DSTATCOM with an objective of minimizing real power loss and operating cost. Installation costs of DSTATCOM devices and the cost of system operation, namely, energy loss cost due to both reconfiguration and DSTATCOM placement, are combined to form the objective function to be minimized. The distribution system tie switches, DSTATCOM location and size have been optimally determined to obtain an appropriate operational condition. In the proposed approach, the fuzzy membership function of loss sensitivity is used for the selection of weak nodes in the power system for the placement of DSTATCOM and the optimal parameter settings of the DFACTS device along with optimal selection of tie switches in reconfiguration process are governed by genetic algorithm(GA). Simulation results on IEEE 33-bus and IEEE 69-bus test systems concluded that the combinatorial method using DSTATCOM and reconfiguration is preferable to reduce power losses to 34.44% for 33-bus system and to 45.43% for 69-bus system.

The Need for Awareness of Drinking Water Loss Reduction for Sustainable Water Resource Management in Rwanda

Drinking water loss or Non-Revenue Water (NRW) threatens the financial viability of water utilities and sustainable natural water resource management. However, little attention has been paid to quantitative assessment of the spatial distribution of water losses in Rwanda. Therefore, this study focused on the magnitude of water losses, the associated environmental and socio-economic consequences, as well as the potential benefits from water loss reduction in Rwanda. Based on water usage records from the Water and Sanitation Corporation (WASAC) of Rwanda, NRW was calculated for 15 WASAC branches and Provinces, from July 2013 to June 2014, by using the International Water Association (IWA) standard water balance approach. The results highlight an annual NRW of 16,502,198 or 41% of the total water produced, inducing a revenue loss of US$ 8,713,156. In 14 of the 15 WASAC water branches and all Rwandan provinces, the NRW ratios exceed the NRW threshold (10%) recommended by the American Water Works Association (AWWA). Because of the lost revenue, the water facilities may not expand quickly enough to meet the demands of the rapidly growing population. The suggested 50% reduction in NRW would provide additional 8,251,100 m3 of treated water yearly, enough to serve extra 41,925 households or irrigate 661 ha of cropland and save US$ 4,356,579, which would reduce the financial gap in Rwanda’s National Water Improvement Project by more than 24%.

Construction of New Value Chain Management and Various BOMs for Research Project of SDGs Food Loss Reduction:Case Studies on Circular Economy Sweets Product Planning,Sales Event Holding,and Questionnaire Surveys

Regarding the social problem of food loss in Japan,about 10%-20%of agricultural products(e.g.vegetables and fruits)are seen as“non-standardized foods”or“surplus foods”by the Agricultural Cooperative Association.Those foods are then discarded.The Tamaki Laboratory of the School of Business,Aoyama Gakuin University is promoting the“SDGs Food Loss Regeneration Project”through industry and academic collaboration—as a research study—to solve this social problem.Therefore,the purpose of this research is the following three subjects:(1)Indicate the design of VCM(value chain management).VCM corresponds to the planning,manufacturing,and sales meetings of“SDGs Moist Vegetable Cake”,and the roles of stakeholders engaged in each area of VCM.(2)Design various BOMs(bill of materials)corresponding to the VCM.Describe how to use BOM and the significance of using each BOM in cooperation.(3)In order to verify the effectiveness of the“SDGs Food Loss Regeneration Project”with“SDGs Moist Vegetable Cake”,conduct and analyze questionnaire surveys and consider the results.

Tip-leakage flow loss reduction in a two-stage turbine using axisymmetric-casing contouring

In order to reduce the losses caused by tip-leakage flow, axisymmetric contouring is applied to the casing of a two-stage unshrouded high pressure turbine（HPT） of aero-engine in this paper. This investigation focuses on the effects of contoured axisymmetric-casing on the blade tipleakage flow. While the size of tip clearance remains the same as the original design, the rotor casing and the blade tip are obtained with the same contoured arc shape. Numerical calculation results show that a promotion of 0.14% to the overall efficiency is achieved. Detailed analysis indicates that it reduces the entropy generation rate caused by the complex vortex structure in the rotor tip region, especially in the tip-leakage vortex. The low velocity region in the leading edge（LE） part of the tip gap is enlarged and the pressure side/tip junction separation bubble extends much further away from the leading edge in the clearance. So the blocking effect of pressure side/tip junction separation bubble on clearance flow prevents more flow on the tip pressure side from leaking to the suction side, which results in weaker leakage vortex and less associated losses.

Optimizing coil configurations for AC loss reduction in REBCO HTS fast-ramping magnets at cryogenic temperatures

AC loss is one of the critical issues for designing REBCO fast‐ramping magnets operating at cryogenic temperatures.There are many ways to reduce AC loss for coil windings.However,it is not clear which method is the most effective way to minimize AC loss in the coil windings for a given Ampere‐turns.In this work,we numerically studied coil configurations of several small superconducting magnets constructed from 12 mm SuperPower REBCO coated conductors,for fast‐ramping application with the same Ampere‐turns to identify the lowest AC loss among them.The HTS magnets have a total turn number of 50 and inner diameter of 30 cm,carrying AC current operating in the temperature range of 20–40 K at 25 Hz.We incorporated several existing loss reduction strategies including spacing between the turns for single pancake coils,grading Ic values for the solenoid configuration,and applying flux diverters to shape the magnetic field around the coil windings.The simulation was implemented using a homogenized H‐formulation.Across all studied loss reduction methods,the use of flux diverters has the largest impact in AC loss reduction.The AC loss values in the solenoid winding comprising a stack of five single pancake coils with 0.1 mm turn‐to‐turn gap with the flux diverters agree well with those in the single pancake coil for 2 mm turn‐to‐turn gap with the flux diverters.Solenoid type coil configurations with flux diverters generate much smaller AC loss than the single pancake type with flux diverters when they generate the same center magnetic field.

Exploration and Practice of Precision Emission Reduction Monitoring System in Air Pollution Prevention and Control in a District of Tianjin

At present,China’s atmospheric environmental protection work has achieved initial results,but environmental protection is facing increasing pressure,and the environmental situation is still not optimistic.In response to the call of the state,efforts have been intensified in environmental protection and ecological civilization construction,and supply-side structural reform has been actively promoted,and the Implementation Plan for Tianjin’s Comprehensive Discharge of Industrial Pollution Sources to Meet Standards has been promoted.When the total amount of pollutants discharged in key areas far exceeds the environmental capacity,regional heavy pollution weather will still occur once adverse meteorological conditions are encountered.In accordance with the Law of the People’s Republic of China on the Prevention and Control of Atmospheric Pollution,when the deterioration of air quality to a certain extent,to protect public health,key gas related industries should carry out emergency emission reduction in accordance with the local emergency plan while the local government starts the emergency response of heavy pollution weather.Direct economic loss of emergency response to heavy pollution weather is enormous.On the basis of meeting the total amount of emissions required by the state,the project aims to achieve the effect of"emission reduction and production increase"by precise emission reduction according to local characteristics.

Ideas of establishing the information system for emergence decisions on the protection against earthquakes and disaster reduction in cities (application of GIS)

ith urban reformation and opening becoming deeper,the work of protection against earthquake and disaster reduction would be more important.In this paper,some ideas are suggested about establishing the information system for emergency decisions on protection against earthquake and disaster reduction in cities .The information system mainly includes a subsystem for rapid evaluation of damage loss from earthquake (which includes input of seismic information,distribution of earthquake intensity,evaluation of seismic fragility on all social factors and etc.) and a subsystem for the decisive information of seismic emergency(which mainly includes project of disaster relief,project of personnel evacuation,dangerous degree warning for the dangerous articlesstoring places and protection measures against them,assistant decision on fire due to earthquake,location of headquarter for providing disaster relief,and etc.). It is thought that the data investigation and collection about all kinds of buildings(including lifeline engineering)are the most important and difficult work as establishing this system.

Shapley value cooperative game theory-based locational marginal price computation for loss and emission reduction

An iterative method based on Shapley Value Cooperative Game Theory is proposed for the calculation of local marginal price (LMP) for each Distributed Generator (DG) bus on a network. The LMP value is determined for each DG on the basis of its contribution to reduce loss and emission reduction, which is assessed using the Shapley Value approach. The proposed approach enables the Distribution Company (DISCO) decision-maker to operate the network optimally in terms of loss and emission. The proposed method is implemented in the Taiwan Power Company distribution network 7 warnings consisting of 84 buses and 11 feeders in the MATLAB environment. The results show that the proposed approach allows DISCO to operate the network on the basis of its priority between the reduction of active power loss and emission in the network.

Effects of Vortex Generator Jet on Corner Separation/Stall in High-Turning Compressor Cascade

The effects of the vortex generator jet(VGJ)attached at the endwall on the corner separation/stall control are investigated by numerical simulation in a high-turning linear compressor cascade. The results show that the corner separation could be reduced significantly, which results in a wider operation range as well as a more uniform exit flow angle and total pressure profile. At the near-stall operation point, the maximum relative reduction of the total pressure loss is up to 32.5%,, whereas the jet mass ratio is less than 0.4%,. Based on the analysis of the detailed flow structure, three principal effects of the VGJ on the endwall cross flow and corner separation are identified. One is to increase the tangential velocity component opposite to cross flow, thus inhibiting the endwall secondary flow near the jet exit. The second is to suppress the pitchwise extension of the passage vortex as an air fence. The third is to sweep the low energy fluids towards the mainstream on the up-washed side and to transport the mainstream fluids to the endwall to reenergize the boundary layer on the down-washed side.

Manufacture of Catalyst Systems for Ammonia Conversion

Platinum catalyst gauzes have been in use since the moment of development of the process of catalyst oxidation of ammonia for production of nitric acid or hydrocyanic acid.Catalyst gauzes are usually made of platinum or its alloys with rhodium and palladium.These precious metals have remarkable properties that make them ideal catalysts for acceleration of the ammonia/oxygen reaction.In 2008,OJSC "SIC 'Supermetal'" and Umicore AG&Co.KG launched a production line for Pt-alloy-based catalyst systems to be used for ammonia oxidation in the production of weak nitric acid.Catalyst systems consist of a pack of catalyst gauzes and a pack of catchment gauzes,which are made using flat-bed knitting machines and wire-cloth looms.Today,up-to-date catalyst systems MKSprecise TM are being manufactured,the basic advantages of which are an individual structure of gauzes and composition of the material,which allows to define precisely the position of each gauze in the catalyst pack,a high activity of the catalyst pack,direct catching of platinum and rhodium in the catalyst system,and a reasonable combination of single-and multilayer types of gauzes.This makes it possible to vary the configuration of the catalyst and select an optimum composition of the system to ensure the maximum efficiency of the ammonia oxidation process.We also produce the catchment systems that allow to find the best decision from the economic point view for each individual case.

An experimental investigation on sound transmission loss and vibration reduction of a vessel in water

Experimental results of sound transmission loss in a range of frequency through bubbly curtains were obtained, where the air content was in a wide range by means of varying pressure differences and the diameters of the pores of bubble-produce apparatus . Vibration reduction of a vessel in water due to the bubbly curtain was found.

Power system reconfiguration and loss minimization for a distribution systems using ＂Catfish PSO＂ algorithm

One of the very important ways to save electrical energy in the distribution system is network reconfiguration for loss reduction. Distribution networks are built as interconnected mesh networks; however, they are arranged to be radial in operation. The distribution feeder reconfiguration is to find a radial operating structure that optimizes network performance while satisfying operating constraints. The change in network configuration is performed by opening sectionalizing （normally closed） and closing tie （normally opened） switches of the network. These switches are changed in such a way that the radial structure of networks is maintained, all of the loads are energized, power loss is reduced, power quality is enhanced, and system security is increased. Distribution feeder reconfiguration is a complex nonlinear combinator- ial problem since the status of the switches is non- differentiable. This paper proposes a new evolutionary algorithm （EA） for solving the distribution feeder reconfiguration （DFR） problem for a 33-bus and a 16- bus sample network, which effectively ensures the loss minimization.

AC loss mitigation for high temperature superconducting coils in wireless power transfer

With the rapid development of high temperature superconducting(HTS)technology,second generation(2G)HTS materials have become a promising alternative to traditional conductive materials in the power transmission industry.Recently,the topic of using HTS materials in wireless power transfer(WPT)systems for electric vehicles(EVs)has attracted widespread attention in the background of net zero transport.With virtually zero DC resistance and superior current‐carrying capacity,HTS materials can achieve high quality factor and power density in the WPT resonant circuits compared to conventional metals,e.g.,copper.However,the optimal working frequency for the conventional WPT system is relatively high in the order of kilohertz level.Superconducting coils working at high frequencies could generate high AC losses,reducing the overall power transfer efficiency(PTE)and increasing the cooling burden.In order to improve the PTE of HTS‐WPT systems,the AC loss mitigation methods for different HTS coil topologies have been investigated in this paper by varying the inter‐turn gap and tape width.Three HTS coil structures,namely the spiral coil,the solenoid coil and the double pancake(DP)coil,have been studied with a 2D axisymmetric multi‐layer numerical model based on the H‐formulation,and the simulation results have been validated by the published experimental data.The general loss characteristics,loss distributions in each turn,as well as magnetic flux densities have been analysed in detail for three types of HTS coils.Moreover,the impact of these two loss reduction methods on the WPT performance has also been evaluated.Findings have shown that increasing the inter‐turn gap and tape width can effectively reduce the AC power losses and increase the PTE of the HTS‐WPT system.The spiral coil demonstrates the highest AC power loss reduction effect and PTE while maintaining a stable level of magnetic fields.This paper is believed to deepen the understanding of superconducting WPT and provide a useful reference for more efficient wireless energisation applications.

U-shaped energy loss curves utilization for distributed generation optimization in distribution networks

We propose novel techniques to find the optimal location,size,and power factor of distributed generation(DG) to achieve the maximum loss reduction for distribution networks.Determining the optimal DG location and size is achieved simultaneously using the energy loss curves technique for a pre-selected power factor that gives the best DG operation.Based on the network's total load demand,four DG sizes are selected.They are used to form energy loss curves for each bus and then for determining the optimal DG options.The study shows that by defining the energy loss minimization as the objective function,the time-varying load demand significantly affects the sizing of DG resources in distribution networks,whereas consideration of power loss as the objective function leads to inconsistent interpretation of loss reduction and other calculations.The devised technique was tested on two test distribution systems of varying size and complexity and validated by comparison with the exhaustive iterative method(EIM) and recently published results.Results showed that the proposed technique can provide an optimal solution with less computation.

Experimental Investigation of Effects of Distributed Riblets on Aerodynamic Performance of a Low-speed Compressor

It is well known that riblet applied on compressor blades is a promising flow control technique. However, detailed investigation of its effects on the flow field of turbomachinery is rare in existing literatures. This paper presents a detailed experimental investigation of effects of distributed riblet on the flow field of an axial compressor iso- lated-rotor stage. The research was performed in a large-scale facility respectively with two configurations, in- eluding grooved hub, and grooved surface on both hub and partial suction surface. The riblet film is rectangle grooved type with a height of 0.1 ram. The flow field at 10% chord downstream from the cascade trailing edge was measured using a mini five-hole pressure probe and a total pressure probe. The testing was conducted at sev- eral operational points under two reduced rotational speeds. Stagnation pressure loss in rotational frame was cal- culated and compared with the control test in which a smooth film was applied to the corresponding position. Results show that with the grooved hub configuration at the design operation point of the lower rotational speed, the riblet film provides an obvious improvement of a 48% reduction of total pressure loss in rotational frame. Also, a distinct weaken hub comer vortex was identified. In the meantime, there exists a deviation of flow angle about 5 degrees at 20%-80% span which previously was not considered to be the affected region.

Development and performance evaluation of a high temperature resistant, internal rigid, and external flexible plugging agent for water-based drilling fluids

During the drilling process for oil and gas production,a larger number of drilling fluids invade the formation,causing severe formation damage and wellbore collapsing,which seriously hinders the efficient production of deep oil and gas.Although several plugging agents have been developed for efficient fracture sealing in recent years,the development of high-performance plugging agents with self-adaptive ability and high-temperature resistance remain a challenge.Herein,we report the synthesis of an internal rigid and external flexible plugging agent PANS by reversed-phase emulsion polymerization with nano-silica as the rigid core and poly(acrylamide-co-N-vinylpyrrolidone)as a flexible shell.The plugging agent has a median particle size of 10.5μm and can self-adapt to seal the microfractures and fractures in the formation,leading to an effective reduction in the filtration loss of bentonite water-based drilling fluid under both low temperature and low pressure(LTLP)and high temperature and high pressure(HTHP)conditions.In addition,compared with the neat nano-silica(500 nm),the sealing efficiency of PANS toward 100–120 mesh sand bed was increased by 71.4%after hot rolling at 180°C.

Fuzzy stochastic long-term model with consideration of uncertainties for deployment of distributed energy resources using interactive honey bee mating optimization

This paper presents a novel modified inter- active honey bee mating optimization （IHBMO） base fuzzy stochastic long-term approach for determining optimum location and size of distributed energy resources （DERs）. The Monte Carlo simulation method is used to model the uncertainties associated with long-term load forecasting, A proper combination of several objectives is considered in the objective function. Reduction of loss and power purchased from the electricity market, loss reduc- tion in peak load level and reduction in voltage deviation are considered simultaneously as the objective functions. First, these objectives are fuzzified and designed to be comparable with each other. Then, they are introduced into an IHBMO algorithm in order to obtain the solution which maximizes the value of integrated objective function. The output power orDERs is scheduled for each load level. An enhanced economic model is also proposed to justify investment on DER. An IEEE 30-bus radial distribution test system is used to illustrate the effectiveness of the proposed method.

Simultaneous allocation of renewable energy sources and custom power quality devices in electrical distribution networks using artificial rabbits optimization

This study suggests an optimal renewable energy source(RES)allocation and distribution-static synchronous compensator(D-STATCOM)and passive power filters(PPFs)for an electrical distribution network(EDN)to improve its performance and power quality(PQ).First,the latest metaheuristic artificial rabbits optimization(ARO)is used to locate and size solar photovoltaic(PV),wind turbine(WT)and D-STATCOM units.In the second stage,ratings of single-tuned PPFs and D-STATCOMs at the RESs are determined,considering non-linear loads in the network.The multi-objective function reduces power loss,improves the voltage stability index(VSI)and limits total harmonic distortion.Simulations using the IEEE 33-bus EDN compared the ARO results with those of previous studies.In the first scenario,ideally integrated D-STATCOMs,PVs and WTs reduced losses by 34.79%,64.74%and 94.15%,respectively.VSI increases from 0.6965 to 0.7749,0.8804 and 0.967.The optimal WT integration of the first scenario outperformed the PVs and D-STATCOMs.The second step optimizes the WTs and PQ devices for non-linear loads.WTs and D-STATCOMs reduce the maximum total harmonic distortion of the voltage waveform by 5.21%with non-linear loads to 3.23%,while WTs and PPFs reduce it to 4.39%.These scenarios demonstrate how WTs and D-STATCOMs can improve network performance and PQ.The computational efficiency of ARO is compared to that of the pathfinder algorithm,future search algorithm,butterfly optimization algorithm and coyote optimization algorithm.ARO speeds up convergence and improves solution quality and comprehension.

Optimal Simultaneous Allocation of Electric Vehicle Charging Stations and Capacitors in Radial Distribution Network Considering Reliability

The popularity of electric vehicles(EVs)has sparked a greater awareness of carbon emissions and climate impact.Urban mobility expansion and EV adoption have led to an increased infrastructure for electric vehicle charging stations(EVCSs),impacting radial distribution networks(RDNs).To reduce the impact of voltage drop,the increased power loss(PL),lower system interruption costs,and proper allocation and positioning of the EVCSs and capacitors are necessary.This paper focuses on the allocation of EVCS and capacitor installations in RDN by maximizing net present value(NPV),considering the reduction in energy losses and interruption costs.As a part of the analysis considering reliability,several compensation coefficients are used to evaluate failure rates and pinpoint those that will improve NPV.To locate the best nodes for EVCSs and capacitors,the hybrid of grey wolf optimization(GWO)and particle swarm optimization(PSO)(HGWO_PSO)and the hybrid of PSO and Cuckoo search(CS)(HPSO_CS)algorithms are proposed,forming a combination of GWO,PSO,and CS optimizations.The impact of EVCSs on NPV is also investigated in this paper.The effectiveness of the proposed optimization algorithms is validated on an IEEE 33-bus RDN.