浅谈光伏发电系统中并网逆变器的设计及系统的工作原理

我国早在20世纪50年代开始研究太阳能电池,于1971年首次成功应用于我国发射的东方红二号卫星。我国的光伏产业发展经历了2个重要时期,第一个是在20世纪80年代中期,引进4条总计5MW的光伏电池生产线,光伏产业初步形成。第二个发展时期是在新世纪初,国家发改委在2002年启动了“送电到乡工程”,该工程光伏系统容量为20MW,极大的拉动了我国光伏市场的需求。国内光伏系统主要采用单位功率因数并网,不具备电能质量控制功能。因此,研究具有电能质量调节功能的光伏并网系统有重要意义。     

数字化三维虚拟演播室系统方案设计

数字化三维虚拟演播室系统将摄像机现场拍摄人物活动图像和三维虚拟物体图像制作进行数字化的实时完美结合.首先介绍了数字化三维虚拟演播室的特点,然后叙述了三维虚拟演播室系统项目需求,最后从设计原则、系统结构设计、系统设备、系统显著特点等方面阐述新余台数字化三维虚拟演播室系统的设计方案.     

The 2013 reforms of the Flemish renewable electricity support: Missed opportunities

The Flemish renewable electricity support system has struggled to address a number of problematic issues in the past. These included excessive profit margins and general malfunctioning of the green certificate market, as well as a lack of qualification of various existing renewable energy technologies. The Flemish government responded to these issues by introducing major reforms in 2013, including “banding” to differentiate the support for various technologies. However, reliable methods for differentiating renewable electricity technologies and calculating support levels have not been sufficiently developed. The main objective of the 2013 reforms was to reduce support costs, but application of German feed-in tariffs on 18 reference technologies has shown that most projects in Flanders continue to receive high levels of support. The 2013 reforms did not succeed in addressing malfunctioning of the green certificate market. On the contrary, the confidence of investors in renewable electricity plants has decreased as the terms of support can be altered retroactively by adjusting remuneration levels and through political interventions. Future adaptations are likely to be made which will further decrease the overall stability and effectiveness of the system.     

140dam3/h制氢装置开工难点与对策

讨论了某公司140 dam3/h制氢装置首次开工过程中遇到的开工难点和对策.装置采用轻烃蒸汽转化制氢技术,由于规模大,开工时系统吹扫、气密、机泵试运等过程有一定困难.通过改造,解决了鼓风机、引风机入口蝶阀不能正常开关等问题,加装轴流风机和百叶窗,降低了转化炉顶环境温度,从界区外倒引中压蒸汽提高了清洁蒸汽汽包煮炉压力,在原料精制部分增加开工氮气线,解决了系统长循环流量不足问题.装置一次开车成功说明采取措施是正确的,开工正常后各项运行参数均处于合理范围,装置运行初期每吨氢气加工能耗47.86 GJ,低于设计值.     

发电系统加强电气自动化技术应用的探讨

随着科技的发展,电气自动化在发电系统中得到了广泛的应用。这使得发电系统的工作效率得到了提高,加强了电气控制的稳定性,给企业与社会提高经济效益。     

Dynamic behavior of a distributed incinerator power system under output power variation

In Taiwan, the sales revenues of power generation from incinerator power plants with heat recovery power generation sold to the power company were up to NT$4.5bn, making the incinerator power generation play an important role in reduction of impact on environment and substitution of energy in power generation. Studying the dynamic behavior of incinerator power systems under output power variation is thus an essential task for the scheduling, operation, and expansion of incinerator power plants, such as, for cooperating with a scheduling program based on pricing signals to capture energy trading timing economically and to operate the incinerator power system securely. Although there are many studies on incinerator power generation, they seldom discuss the power generation system characteristics. In this paper, mathematical dynamic models for a distributed incinerator power system were derived and implemented using Matlab/Simulink, and dynamic characteristics of the system were further simulated and discussed under two operating modes: increment and decrement of power generation. These developed models can provide dynamic characteristics for these two modes, serving as an important analytic tool for cooperating with a scheduling program based on pricing signals to capture energy trading timing economically and to operate the incinerator power system securely. Copyright © 2014 John Wiley & Sons, Ltd.     

Distensible air accumulators as a means of adiabatic underwater compressed air energy storage

In the near future, the electricity industry is likely to face historically significant changes. The onset of distributed generation, micro and smart grids will change the entire structured industry. An influx of intermittent renewable generators will make traditional grid balancing notably more difficult. The novel concept of underwater compressed air energy storage is a potentially promising solution that may be used to meet these challenges, especially during the current period of electrical infrastructure renewal and modernisation. Early results from a Lake Ontario Pilot Study point to the potential viability of the concept.     

Evaluation of expected energy generation in multi-area interconnected systems with photo voltaic generating units

This paper presents a methodology which extends the segmentation method to evaluate the expected energy generation and the expected export/import among the electrical utilities in an interconnected system with renewable energy-based units as well as conventional thermal units. The proposed methodology is applied to the Power Grid of Bangladesh. The method helps the system planner determine the expected cost of energy generation of various sources. The randomness in the output of a renewable energy generator is appropriately modelled in the proposed methodology.