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含冷热电三联供的微能源网能量流计算及综合仿真 被引量:54
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作者 马腾飞 吴俊勇 郝亮亮 《电力系统自动化》 EI CSCD 北大核心 2016年第23期22-27,124,共7页
首先给出了微能源网的定义,然后基于能源集线器的概念,建立了冷热电三联供(CCHP)系统的能量流模型;并将其作为配电网与天然气网的耦合节点,推导了适用于天然气网能量流计算的有限元节点法,提出了一种电—气耦合微能源网的能量流计算方... 首先给出了微能源网的定义,然后基于能源集线器的概念,建立了冷热电三联供(CCHP)系统的能量流模型;并将其作为配电网与天然气网的耦合节点,推导了适用于天然气网能量流计算的有限元节点法,提出了一种电—气耦合微能源网的能量流计算方法。提出了CCHP供能率的指标。以openDSS和MATLAB为平台,对含CCHP的微能源网进行综合仿真,分别计算了以电定热和以热定电两种典型运行方式下夏季典型日的逐时能量流。计算结果表明,所提出的能量流计算和综合仿真方法可用于分析微能源网的能量流,CCHP供能率指标可以反映微能源网电—气能源的耦合程度。 展开更多
关键词 能源互联网 微能源网 能源集线器 天然气网 有限元节点法 能量流 openDSS 供能率
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Numerical Analysis of Influencing Factors on Temperature Field and Airflow Distribution of the Displacement Ventilation System 被引量:1
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作者 那艳玲 邢金城 +1 位作者 涂光备 于松波 《Transactions of Tianjin University》 EI CAS 2005年第1期66-72,共7页
Indoor air quality and thermal comfort are important features of indoor environment. In this paper, a numerical simulation based on the k-ε model of CFD is used to analyze factors such as loading, exterior-protected ... Indoor air quality and thermal comfort are important features of indoor environment. In this paper, a numerical simulation based on the k-ε model of CFD is used to analyze factors such as loading, exterior-protected construction, blowing-in rate that play an important role in the temperature field and airflow field of the displacement ventilation system. Exterior-protected construction has little influence on indoor temperature distribution of displacement ventilation systems and the influence is limited only in a small area near the external wall when the indoor heat source is the main cooling load.The height of a room has little influence on indoor temperature field, and the temperature gradient of active region is basically unchanged. In the system combined with a displacement ventilation system and a cooling system, the height also has little influence. When the cooling load is high,the indoor heat source creates a strong convective plume, which will make the average indoor air age lower, the ventilation efficiency higher and the elimination of pollutant easier. Air supply rate plays an important role in displacement ventilation systems. The increase of air supply rate that can be realized by increasing the air supply velocity and enlarging the area of air inlet will increase the mass capability of the system and diminish the vertical temperature gradient. From the comparison between simulations and experiments, it is concluded that this simulation are creditable. 展开更多
关键词 cooling load exterior-protected construction air supply rate CFD numerical simulation ENERGY-SAVING
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Energy efficiency performance of multi-energy district heating and hot water supply system 被引量:2
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作者 金楠 赵靖 朱能 《Journal of Central South University》 SCIE EI CAS 2012年第5期1377-1382,共6页
A district heating and hot water supply system is presented which synthetically utilizes geothermal energy,solar thermal energy and natural gas thermal energy.The multi-energy utilization system has been set at the ne... A district heating and hot water supply system is presented which synthetically utilizes geothermal energy,solar thermal energy and natural gas thermal energy.The multi-energy utilization system has been set at the new campus of Tianjin Polytechnic University(TPU),A couple of deep geothermal wells which are 2 300 m in depth were dug,Deep geothermal energy cascade utilization is achieved by two stages of plate heat exchangers(PHE) and two stages of water source heat pumps(WSHP).Shallow geothermal energy is used in assistant heating by two ground coupled heat pumps(GCHPs) with 580 vertical ground wells which are 120 m in depth.Solar thermal energy collected by vacuum tube arrays(VTAs) and geothermal energy are complementarily utilized to make domestic hot water.Superfluous solar energy can be stored in shallow soil for the GCHP utilization.The system can use fossil fuel thermal energy by two natural gas boilers(NGB) to assist in heating and making hot water.The heating energy efficiency was measured in the winter of 2010-2011.The coefficients of performance(COP) under different heating conditions are discussed.The performance of hot water production is tested in a local typical winter day and the solar thermal energy utilization factor is presented.The rusults show that the average system COP is 5.75 or 4.96 under different working conditions,and the typical solar energy utilization factor is 0.324. 展开更多
关键词 geothermal energy solar thermal energy district heating hot water supply
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Traffic-prediction-assisted dynamic power saving mechanism for IEEE 802.16e wireless MANs 被引量:1
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作者 陆绍飞 王建新 +1 位作者 荣辉桂 秦拯 《Journal of Central South University》 SCIE EI CAS 2013年第6期1552-1558,共7页
How to reduce the energy consumption powered mainly by battery to prolong the standby time is one of the crucial issues for IEEE 802.16e wireless MANs.By predicting the next downlink inter-packet arrival time,three tr... How to reduce the energy consumption powered mainly by battery to prolong the standby time is one of the crucial issues for IEEE 802.16e wireless MANs.By predicting the next downlink inter-packet arrival time,three traffic-prediction-assisted power saving mechanisms based on P-PSCI,i.e.,PSCI-PFD,PSCI-ED and PSCI-LD,were proposed.In addition,the corresponding adjustment strategies for P-PSCI were also presented when there were uplink packets to be transmitted during sleep mode.Simulation results reveal that compared with the sleep mode algorithm recommended by IEEE 802.16e,the proposed mechanism P-PSCI can improve both energy efficiency and packet delay for IEEE 802.16e due to the consideration of the traffic characteristics and rate changes.Moreover,the results also demonstrate that PSCI-PFD (a=-2) significantly outperforms PSCI-ED,PSCI-LD,and the standard sleep mode in IEEE 802.16e is in terms of energy efficiency and packet delay. 展开更多
关键词 sleep mode power saving traffic prediction IEEE 802.16e
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Energy Efficiency Optimization in Relay-Assisted Networks with Energy Harvesting Relay Constraints 被引量:5
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作者 ZHAO Ming ZHAO Jing +2 位作者 ZHOU Wuyang ZHU Jinkang ZHANG Sihai 《China Communications》 SCIE CSCD 2015年第2期84-94,共11页
In this paper we consider data transmission in a decode-and-forward(DF)relay-assisted network in which the relay is energy harvesting(EH) powered while the base station(BS) is power-grid powered.Our purpose is to maxi... In this paper we consider data transmission in a decode-and-forward(DF)relay-assisted network in which the relay is energy harvesting(EH) powered while the base station(BS) is power-grid powered.Our purpose is to maximize the BS's energy efficiency(EE) while making full use of the relay's renewable energy and satisfying the specific average throughput requirements.In contrast to existing literature on energy harvesting system which only considers the radio transmission power,we take the static circuit power into account as well.We formulate the EE optimization problem and prove that the EE of the BS and relay are both quasiconvex in the instantaneous transmission rate.Then we divide the complex optimization problem into two point-to-point link level optimization parts and propose an energyefficient resource allocation(EERA) scheme in which power control and sleep mode management are jointly used.The simulation results demonstrate that EERA may achieve good energy saving effects.We also compare the EE of an energy harvesting relay system with a power-grid powered one and provide more insight into the EE problem of energy harvesting relay system. 展开更多
关键词 energy efficiency energy harvesting relay sleep mode
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New type steam turbine for cogeneration
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作者 He Jianren Yang Qiguo Xu Damao 《Engineering Sciences》 EI 2010年第3期81-84,共4页
A concept of energy saving & efficiency improving from cold source for cogeneration steam turbine was discussed herein. A new type "NCB" cogeneration steam turbine was proposed,which could considerably i... A concept of energy saving & efficiency improving from cold source for cogeneration steam turbine was discussed herein. A new type "NCB" cogeneration steam turbine was proposed,which could considerably increase heat supply capacity,thermal efficiency and electric power. Taking 300 MW cogeneration steam turbine as an example,the results show that heat supply capacity reaches the maximum,i.e. increases by 30 %,thermal efficiency is improved by 12 %,and electric power is enhanced by 15 MW during peak heat load. 展开更多
关键词 cold source new type cogeneration steam turbine energy saving emission reducing economic effect
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A Neuro-Fuzzy Based Adaptive Set-Point Heat Exchanger Control Scheme in District Heating System
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作者 Liang Huang Zaiyi Liao Zhao Lian 《Journal of Civil Engineering and Architecture》 2012年第11期1584-1588,共5页
The control of heat exchange stations in district heating system is critical for the overall energy efficiency and can be very difficult due to high level of complexity. A conventional method is to control the equipme... The control of heat exchange stations in district heating system is critical for the overall energy efficiency and can be very difficult due to high level of complexity. A conventional method is to control the equipment such that the temperature of hot water supply is maintained at a set-point that may be a fixed value or be compensated against the external temperature. This paper presents a novel scheme that can determine the optimal set-point of hot water supply that maximizes the energy efficiency whilst providing sufficient heating capacity to the load. This scheme is based on Adaptive Neuro-Fuzzy Inferential System. The aim of this study is to improve the overall performance of district heating systems. 展开更多
关键词 District heating system NEURO-FUZZY inferential sensor energy efficiency CONTROL
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Modeling Relative Humidity Effects on Power Electronic Performance
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作者 R. Ciprian B. Lehman 《Journal of Energy and Power Engineering》 2011年第7期632-640,共9页
Variations in the behavior of power supplies caused electrical behavior dependence with environmental conditions. by environmental conditions require accurate characterization of the This paper introduces models to he... Variations in the behavior of power supplies caused electrical behavior dependence with environmental conditions. by environmental conditions require accurate characterization of the This paper introduces models to help predict relative humidity (Rtt) and other environmental factors influence on sensitive circuitry in power electronic systems. The resistivity and permittivity of an insulator have been modeled using different water contents i.e. RH, such model also included the mechanical properties of the design. An application example of a high power density, high voltage DC-DC converter is used to verify the results. 展开更多
关键词 Power electronics insulator resistivity relative humidity insulator permittivity modeling.
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