abstractIn the paper, a new type of wind-solar hybrid system was proposed, in which multiple small windturbines took the place of a bigger one. The electricity performance of the multi-turbine wind-solarhybrid system was studied in comparison with the traditional system. Two types of wind-solar hybridsystem with the same capacity were set up in Tianjin, and the power output of the two systems weremeasured and simulated by the TRNSYS software. The results showed that, at low wind speed, the multi-turbine wind-solar hybrid system has more power production than the reference system. The simulatedresults agreed well with the experiment results. Then, the electricity performance of the multi-turbinewind-solar hybrid system was studied under various climates in China by the TRNSYS. The simulationresults showed that the power output of the wind turbines in multi-turbine wind-solar hybrid systemincreases by 18.69%, 31.24% and 53.79%, when used in Shenyang, shanghai and Guangzhou, respectively,compared with the reference system.© 2014 Elsevier Ltd. All rights reserved. 37449IntroductionWind energy has beenwidely used inmany fields, such as streetlighting, water pumping [1,2] and stand-alone or grid-connectedgenerating power system [3] etc. However, a drawback of thewind energy is that the output power depends largely on the un-predictable weather or climatic changes. The power generated bythe wind turbine does not meet the demand, and neither does thesolar energy system.There is the complementarity between the solar energy and thewind energy. For example, in China, high solar irradiation and poorwind energy emerge in summer, whilst a relatively abundant windenergy and poor solar irradiation occur in winter [4]. Meanwhile,there is high solar irradiation and relatively low wind energy in thedaytime, while there is high wind energy but little solar irradiationat night. In the wind-solar hybrid system, one source of energy canoffset the shortfall of the other, which can greatly meet the loaddemand. Besides, wind-solar hybrid system can improve thegenerating capacity factor which leads to fewer batteries to over-come the unpredictable electric demand.A wind-solar hybrid system was usually comprised of windturbine, photovoltaic (PV) modules, controller, inverter and batteries. The major advantage of the hybrid system is that itsreliability is enhanced compared with the simple wind energysystem or solar energy system [5,6]. The research on wind-solarhybrid system mainly focuses on the modeling for system config-uration, optimal matching between wind turbine and PV modules[7e11], as well as simulation of power output [12e15]. Nema [16]analyzed the future development of renewable systems and theacceptance by users. Celik [5] presented the techno-economicanalysis of wind-solar system using different sizing method.In China, only 1% of areas are suitable for the large-scale windturbine, 10% for turbines lower than 100 kW, and more than 40%for turbines lower than 10 kW [17]. So there is a large marketpotential for small wind turbines to be installed on the yard, farmsand rural area. The multi-turbine wind power system [18e20],which consists of more than one small wind turbine on the sametower, has greater advantages compared with the big turbine atthe same power. For example, when one of the turbines isdamaged, it has little effect on the system. Peter Jamieson [21]compared the cost and O&M of 20 MW wind power system witha 20 MWconventional wind turbine, 4   5 MWwind turbines and45   444 KW wind turbines. The result shown that the45   444 KW system can reduce cost to ～89% of four 5 MW tur-bines or ～70% of a 20 MW single turbine system. The small windturbine may start at lower wind speed than the big one, so themulti-turbine can harvest more wind energy, which makes thehybrid system more reliable. In this paper, a multi-turbine wind-solar system (namely thenew hybrid system) is proposed to get more smoother power. Theperformance of the new system and the reference system wasstudied using the TRNSYS software, which will help to design thenew hybrid system according to the actual demand and naturalconditions.2. Experiment2.1. Components of the hybrid systemThe new system and the reference system were set up in therural areas in Tianjin. The components of the two systems are listedin Table 1. All the equipment of the two systems are the same,except for the wind turbines. The swept area of the 50 W windturbine and the 400 W is 0.635 m2and 2.009 m2, respectively.The structure of the multi-turbine wind power system is shownin Fig. 1. The system is composed of eight 50 W wind turbines,tower, swivel bearing, tail vane and dragline. The eight 50 W windturbines share a tower and a tail vane. The tower is consisted of twosections, the lower section and the upper section. The eight windturbines and tail vane are installed on the upper section and thelower section is fixed by the dragline. Both sections are connectedby swivel bearing, and the whole upper part can round freelyagainst the wind.A very important parameter for designing the hybrid system isthe nominal voltage of the components, including the PV modules,batteries, wind turbines, controller and inverter. In the paper, thenominal voltage of the two systems is set as 24 V. 37449
The nominalvoltage of the eight wind turbines is 12 V, so they are pided intofour groups, each group consists of two turbines connected in se-ries, and the four groups are connected in parallel.2.2. TestThe data acquisition system is shown in Fig. 2. The solar irra-diation was measured by a pyranometer (TBQ-DLyJinzhou solarMeteorological Science and Technology Co., Ltd.). Wind speed wasmeasured by an anemometer (FC-2ByBeijing FCWind Control Co.,Ltd.) installed on the tower. The voltage and current of the PVmodules, turbines and batteries were allmeasured and recorded bythe computer. The test was operated from April 3, 2013 to April 13,2013.3. TRNSYS simulationTRNSYS is a transient system simulation programwith modularstructure. It recognizes system description language in which theuser specifies the components that constitute the system and themanner in which they are connected. The TRNSYS library includesmany components commonly found in thermal and electricalTable 1Components of the two hybrid systems.Component New system Referred system ManufacturerPV module Top-140(12)   2 Top-140(12)   2 Tianjin Lingwei PhotovoltaicScience and Technology Ltd.Wind turbine Z-50W   8 Shenzhen LvdiankangTechnology Co., Ltd.EW-400   1 Yangzhou Shenzhou WindGenerator Co., Ltd.Battery NP100-12   4 NP100-12   4 Yangzhou Yongda Power Co.Inverter WI10-24 WI10-24 Hefei Weimin Power Co.Controller WWS06-24-N01 WWS06-24-N01 Hefei Weimin Power Co. energy systems, as well as component routines to handle input ofweather data or other time-dependent forcing functions andoutput of simulation results. The modular nature of TRNSYS givesthe programtremendous flexibility, and facilitates the addition intothe program of mathematical models not included in the standardTRNSYS library. TRNSYS is well suited to detailed analysis of anysystem whose behavior is dependent on the time. It is convenientfor us to simulate the wind-solar hybrid system [22].3.1. Model of the systemThe simulation models of the two hybrid systems are shown inFig. 3, which are used to forecast the electricity output. All thecomponents of the systems are from the TRNSYS library. Themeteorological parameters used in the simulation are measured onthe experimental site. The anemometer in both systems is installedat the height of 10mon the tower, and the irradiation data are from latitude of 38 340N and a longitude of 118 1940E. The main climaticfeature of Tianjin is hot and dry in summer. The solar irradiation isabundant from March to October.Each system has two crystalline PV modules. The installationangle of the PV modules is 45  and the modules are faced to south.The parameters of the module, which was provided by the manu-facturer, are shown in Table 2.3.4. Load profileThe two hybrid systems are used to offer electricity power for aguard room of our experiment base. The loads include four 15 Wbulbs, one 150 W refrigerator, one 300 W washing machine, one1000 W electric kettle and one 45 W television. The typical loadprofile of each hybrid system in a day is shown in Fig. 5, which isbased on the hourly average energy consumption. It is assumedthat the everyday load is the same. 4. Results and analysis4.1. Validation of the simulationThe simulated and experimental power output of the eight 50Wturbines and the 400 W turbine is shown in Fig. 6a and b respec-tively. It can be seen that the simulated results of the two systemsagreed well with the experimental results, The initial value at thestart time is zero, which was given by the software automatically.The simulated and experimental power output of the PV mod-ules is shown in Fig. 7. The irradiation data was measured on April8, 2013. The simulated results agreed well with the experimentalresults. Atmid noon, the power output of the PVmodules is slightlyhigher than 280 W(nominal rated power)because the rated poweris tested at the standard condition (1000 W/m2and 25  C), whilethe experiment is operated at the temperature of 10  C. The effi-ciency of the PV modules enhances at lower temperature, whichincreased the power output of PV modules 多机风力太阳能混合动力系统英文文献和中文翻译:http://www.youerw.com/fanyi/lunwen_36201.html