Energy efficiency of milling machining: Component modeling and online optimization of cutting parameters

Shin, S.J.,Woo, J.,Rachuri, S. Butterworth-Heinemann, Ltd 2017 Journal of cleaner production Vol.161 No.-

Energy consumption is a major sustainability focus in the metal cutting industry. As a result, process planning is increasingly concerned with reducing energy consumption in machine tools. The relevant literature has been categorized into two research areas. The first includes energy prediction models, which characterize the relationships between cutting parameters - the main outputs of process planning - and energy consumption. The second involves energy-consumption optimization, which uses the prediction models to find the cutting parameters that minimize energy use. However, previous energy prediction models are limited to predict energy for tool paths coded in a Numerical Control (NC) program. Previous energy optimization methods typically do not use online optimization, which enables fast optimization decision-making for supporting on-demand process planning and real-time machine control. This paper presents a component-based energy-modeling methodology to implement the online optimization needed for real-time control. Models that can predict energy up to the tool path-level at specific machining configurations are called component-models in this paper. These component-models are created using historical data that includes process plans, NC programs, and machine-monitoring data. The online optimization is implemented using a dynamic composition of component-models together with a divide-and-conquer technique. The feasibility and effectiveness of our methodology has been demonstrated in a milling-machine example.

Simulation-based machining condition optimization for machine tool energy consumption reduction

Lee, Wonkyun,Kim, Seong Hyeon,Park, Jaesang,Min, Byung-Kwon Elsevier 2017 JOURNAL OF CLEANER PRODUCTION Vol.150 No.-

<P><B>Abstract</B></P> <P>Optimizing the machining condition is one of the effective ways for reducing the energy consumption of machine tools at a unit process level. Based on statistical approaches with design of experiments, various methods have been developed to reduce the energy consumption by optimizing the machining condition. However, the methods cannot be easily utilized when the optimization target or machine tool design is modified because the optimal solution is determined based on the experimentally measured data. In this study, a simulation-based method that utilizes a virtual machine tool (VMT) to optimize the machining condition is proposed. The VMT model is designed to focus on estimating the energy consumption during machining and is developed by replicating real machine tools. Based on the VMT model, a genetic algorithm is used to optimize the machining condition to reduce the energy consumption. The changes in the optimization target or machine tool design are easily considered by modifying the cost function or component model, respectively. The proposed method is applied to reduce the energy consumption of a three-axis milling machine. The optimal feed rate and spindle speed are obtained for each line of the part program when the thrust force is limited. An experimental setup of the machine tool with an energy consumption monitoring system is constructed to demonstrate the effectiveness of the proposed method. The results show that the total energy consumption of the machine tool reduces by 13% owing to the optimization.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Simulation-based method to reduce the energy consumption of machine tool is proposed. </LI> <LI> Virtual machine tool to estimate the energy consumption during machining is built. </LI> <LI> Optimal machining conditions to minimize the energy consumption is obtained. </LI> <LI> Energy consumption reduction using proposed method is demonstrated experimentally. </LI> </UL> </P>

Policy research and energy structure optimization under the constraint of low carbon emissions of Hebei Province in China

Wei Sun,Minquan Ye,Yanfeng Xu 대한환경공학회 2016 Environmental Engineering Research Vol.21 No.4

As a major energy consumption province, the issue about the carbon emissions in Hebei Province, China has been concerned by the government. The carbon emissions can be effectively reduced due to a more rational energy consumption structure. Thus, in this paper the constraint of low carbon emissions is considered as a foundation and four energies--coal, petroleum, natural gas and electricity including wind power, nuclear power and hydro-power etc are selected as the main analysis objects of the adjustment of energy structure. This paper takes energy cost minimum and carbon trading cost minimum as the objective functions based on the economic growth, energy saving and emission reduction targets and constructs an optimization model of energy consumption structure. And empirical research about energy consumption structure optimization in 2015 and 2020 is carried out based on the energy consumption data in Hebei Province, China during the period 1995-2013, which indicates that the energy consumption in Hebei dominated by coal cannot be replaced in the next seven years, from 2014 to 2020, when the coal consumption proportion is still up to 85.93%. Finally, the corresponding policy suggestions are put forward, according to the results of the energy structure optimization in Hebei Province.

플러스에너지빌딩 미래혁신기술

강용태(Yong Tae Kang),김용찬(Yongchan Kim),이호성(Hoseong Lee),송주영(Joo Young Song) 대한설비공학회 2020 대한설비공학회 학술발표대회논문집 Vol.2020 No.6

중국 베이징 지역의 준 제로에너지 주택의 에너지 성능 최적화 방안

진해조 ( Chen Hai-chao ),이상훈 ( Lee Sang-hoon ) 충북대학교 건설기술연구소 2020 建設技術論文集 Vol.39 No.1

중국은 급속한 도시화 시대에 경제와 사회의 급속한 발전과 사람들의 생활수준의 지속적인 개선으로 인해 에너지와 환경 사이에 갈등이 갈수록 심화되고 있다. 건물 총 에너지 소비량과 에너지 소비 강도에 대한 압력이 계속 증가하고 있다. 현재 속도로 계속 성장한다면 건물 관련 탄소 배출량은 2050년까지 두 배가 될 것이므로 건물 에너지 효율 표준의 지속적인 개선을 통해 건물에 대한 특별한 에너지 절약 배출 감소 작업을 수행해야한다. 한랭 지역의 지역 특성에 적합한 설계 전략을 모색하고 주택의 에너지 수요를 줄일 수 있는 녹색 외곽을 개발한다는 목표를 달성할 수 있으며 주택의 초기 계획단계에서 활용을 목적으로 한다. 본 연구에서는 DesignBuilder 해석 시뮬레이션 프로그램을 통해 준제로 에너지 주택의 시뮬레이션 분석 모델을 구축하였으며, 중국 한랭 지역 대표 도시의 기후 데이터를 EnergyPlus 프로그램을 통한 시뮬레이션 분석에 사용 하였다. 입력 및 출력 데이터를 얻다. <준 제로에너지 건축 기술 표준>의 지표에 따라 EnergyPlus 프로그램을 사용하여 최적화 시뮬레이션 분석을 수행하였다. 연구를 통해 외곽의 준제로 에너지 주택에 적용된 성능에 따른 재료두께 및 에너지 요구량 분석을 시행하였으며 에너지 및 성능이 동시에 최적 평가기준을 만족하는 것으로 분석되었다. At the 21st United Nations Climate Change Conference, the whole life cycle of buildings account for 30% of the total global carbon emissions. If this rate continues, carbon emissions of buildings will double by 2050. With the rapid urbanization, economic and social development as well as continuous improvement of people’s living standards, contradictions between energy and environment in China are increasingly prominent, and the upward pressure on total energy consumption and intensity of buildings is increasing. As a consequence, it is necessary to improve the energy-saving standards of buildings, and conduct special energy conservation and emission reduction of buildings. The study with DesignBuilder program to establishes a simulation analysis model of Nearly Zero Energy House; based on the climate data of representative cities in the cold regions of China, it makes a simulation analysis with DesignBuilder program, gaining the input and output data; and according to the index of "Technical Standard for Nearly Zero Energy Building", it conducts an Optimization simulation analysis with EnergyPlus program. larger amount is required in order to be optimal, obtaining the Optimization Building Envelope performance with minimal use of energy.

Multi-objective energy-cost design optimization for the variable-speed wind turbine at high-altitude sites

Song, Dongran,Liu, Junbo,Yang, Jian,Su, Mei,Yang, Sheng,Yang, Xuebing,Joo, Young Hoon Elsevier 2019 Energy conversion and management Vol.196 No.-

<P><B>Abstract</B></P> <P>As the development of wind power utilization, onshore wind turbines have been installed at various sites with different altitudes. Although the site-specific design is an effective way to reduce the levelized energy cost of the wind turbines, the influence of the site altitude on the energy cost is not considered in the existing site-specific designs. To fill the knowledge gap, this study presents the site-specific design optimization of the wind turbines at the high-altitude sites, based on a multi-objective trade-off between maximization of the energy production and minimization of the production cost. For this purpose, two improved estimation models of the annual energy production and the annual production cost are firstly introduced for the high-altitude wind turbines. On this basis, the multi-objective energy-cost optimization problem is formulated as two nonlinear functions relevant to two key designed parameters: the rated power and the rotor radius. After that, a multi-objective particle swarm optimization method is proposed. Finally, the proposed method is applied to the Huitengxile and Maanshan wind farms, located in Inner Mongolia and Yunnan-Kweichow plateaus of China, respectively. The results show that the energy cost has been noticeably increased by about 15% and 18% in the two applications comparing with the results ignoring the site altitude. Moreover, a trade-off between various alternative energy-cost solutions has been provided by the generated set of the optimally designed parameters. Thus, a two-step criterion has been proposed to help the turbine designers select the designed parameters according to their preference.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Multi-objective optimization for the site-specific turbine design. </LI> <LI> Improved energy and cost estimations for the high-altitude wind turbine. </LI> <LI> Proposed method applied to two high-altitude wind farms. </LI> <LI> Trade-off results between the energy and the cost in the two applications. </LI> <LI> Novel two-step criterion for selecting the optimally designed parameters. </LI> </UL> </P>

Distributed Energy Generation and Flow Optimization: A Simultaneous Approach

Phuong Huu Hoang,Chuong Van Nguyen,Hyo-Sung Ahn 제어로봇시스템학회 2018 제어로봇시스템학회 국제학술대회 논문집 Vol.2018 No.10

Energy generation and flow optimization is one of primary concerns in distributed energy grids. Typically, optimal energy generation and optimal flow are studied separately. In this paper, we propose an optimization algorithm which considers both energy generation and energy flow simultaneously. We construct a dynamical system to seek the optimal solution for both energy generation and energy flow. The theoretical guarantee of the proposed algorithm is provided. In addition, we carry out a numerical simulation to demonstrate the correctness of the strategy.

Wind farm layout optimization for wake effect uniformity

Yang, Kyoungboo,Kwak, Gyeongil,Cho, Kyungho,Huh, Jongchul Pergamon Press 2019 Energy Vol.183 No.-

<P><B>Abstract</B></P> <P>The basic objective of wind farm layout optimization is to maximize the energy produced by wind farms. However, when wind turbines are arranged in a limited space like an onshore wind farm, specific wind turbines may have greater wake exposure than other wind turbines. This phenomenon can be conspicuous in a mixed layout that consists of turbines with different capacities and hub heights. In this study, we developed and tested a new objective function to increase wind farm energy output while making the wake loss of each wind turbine uniform. The purpose of this function is to adjust the wake effects of all of the wind turbines on a wind farm to similar levels, thereby promoting the operational stability of all of the wind turbines. Layout optimization was performed using a simulated annealing algorithm, which is a heuristic method, with actual wind conditions for an existing wind farm in operation. Then, the results obtained using the proposed method were compared with those yielded by layout optimization for energy maximization. The layout generated using the proposed objective function had lower energy output than that obtained by energy maximization. However, this difference was small and the proposed method prevented wake effect concentration on specific turbines by making the wake effect levels uniform.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A simulated annealing algorithm is suggested for wind farm layout optimization. </LI> <LI> An objective function for wind turbine wake effect uniformity is proposed. </LI> <LI> Wind turbine layout optimization was performed for an existing wind farm. </LI> <LI> The optimal layouts for energy maximization and wake effect uniformity were compared. </LI> <LI> The proposed objective function increased energy and reduced wake effect deviation. </LI> </UL> </P>

Optimal Sizing in Hybrid Renewable Energy System with the Aid of Opposition Based Social Spider Optimization

S. R. Sandeep,Rudranna Nandihalli 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.1

Rely on fossil fuels for several decades deplete the source and pollute environment drastically, these signifcant impact contemplates and urge seeking alternate energy. Renewable energy plays a vital role in compensating power demands and ecofriendly source of alternate energies. Despite, individual standalone source of renewable energy is inadequate to fulfll power demand and this urge hybrid renewable energy power generation. This research work incorporate solar photovoltaic and wind energy power generations as hybrid form of renewable energy to compensate power demands. This objective pursue with optimal sizing of enroll equipment responsible to compensate power demand. To pursue the research objective through manual take a long time to compute which pave the path of incorporating optimization techniques in the context of confguring appropriate generating and backup units to satisfy power demand in economic cost. The techniques intend to employ in this research are particle swarm optimization, artifcial fsh swarm optimization, adaptive genetic algorithm with Cauchy mutation (AGA-Cauchy), social spider optimization and opposition based social spider optimization (OSSO). It is apparent in the following results that OSSO a swarm intelligence techniques unveil profcient performance over contest techniques.

마이크로 에너지 그리드 기술 적용 통합에너지운영센터 공간 계획에 관한 기초 연구

오현인(Oh, Hyun-In),조보형(Cho, Bo-Hyung) 한국실내디자인학회 2013 한국실내디자인학회 학술대회논문집 Vol.15 No.1

A new urban paradigm “green city” has emerged with the incorporation of smart grid technology into urban infrastructure. As an integral part of the green city, the integrated energy operations center is an information processing and service platform for the efficient use and management of energy. The next-generation energy technology “micro energy grid” is characterized as a combination of technologies for smart grids, power decentralization and use of final energy (i.e. heat, electricity, gas, etc.) and provides a total energy solution that can underlie the realization of energy-sufficient cities (and buildings) by ensuring the efficiency of energy production and consumption. The present study aims to propose a space plan for the integrated energy operations center based on communication infrastructure and interfaces for such micro energy grids. In addition, this study attempts to suggest a more advanced energy operations center for automation technologies and services with the application of the micro energy grid technology to a real-world building (test bed).