Power & Energy Solutions

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In response to the global market requirement for more efficient and targeted O&M strategies for operational wind farms, there is an increasing need for operators to focus on turbine performance and reliability. Having recognised this as a priority to support operational teams and to advise on strategies to optimise sites, our approach has been to research, develop and implement several new methodologies that highlight short and long-term considerations for operations and asset management (O&M) planning across client portfolios, advanced performance engineering (APE). The detailed analysis of wind regimes can pinpoint the optimum time frame for undertaking maintenance activities to ensure revenue losses are minimised; whilst turbine benchmarking assessments can identify trends specific to individual technologies and therefore highlight and inform the future management and maintenance of wind farms. In this article, we will take a look at the role of APE and how it can aid operators in their decision making. We begin with the drivetrain of a wind turbine which is one of the most expensive and important components of its mechanical functionality. As such, it is standard practice for a site to have measures in place to monitor the health of the drivetrain components. These include remote systems such

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DFIG topology wind turbines have been widely used in the wind energy market during the last years to cover the medium and lower power ranges, between 2 and 4 MW. Nowadays, this fact has changed and the OEMs are developing DFIG wind turbines that could go above power rates of 6 MW. The wind sector is globally focusing its efforts on reducing the Levelized Cost of Energy (LCoE) of the technology in order to prove itself as a profitable option in the energy mix regarding electrical generation. In response to this market outlook, OEMs are working hard to develop wind turbines with a power range exceeding 6 MW, which potentially enables the reduction of the LCoE of the wind farm. In addition, the increasing penetration of wind power capacity into the grid creates new challenges for the Transmission System Operators (TSO) in order to keep the stability of the transmission system. As a consequence, grid codes around the world are strengthening their requirements to meet more demanding conditions such as FRT (Fault Ride-Through) behavior or harmonic distortion compliance.

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Abstract: full-scale mechanical testing of blades is an integral part of the certification of wind turbines. With ever-larger rotor diameters, the importance of testing and validation is growing with the aim of minimizing operational risks. Dual axis testing can lead to a more realistic loading scenario compared to traditional single axis testing. A recent demonstration at Fraunhofer IWES revealed that spring elements and decoupled masses can be used to tune the system frequencies, resulting in a representative dual-axis test. Full-scale mechanical testing In the race to maximize annual energy production (AEP), rotor diameters are continuing to grow. The increasing size of the turbine blades means that fewer test facilities are able to accommodate mechanical testing of the latest blade models. Limiting factors for the capacity to test turbine blades are the length of the test hall and the hall height, which is required to accommodate the large deformations during both static and dynamic testing. However, the most crucial factor is the ability of the test rig to bear both static and fatigue bending moments.

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新系统安装完毕或现有系统维护完毕后,常出现渗漏。造成该情况的原因通常是连接出错或误用了有缺陷的密封件。若想及时发现该渗漏情况并有效管控设备的密封性,正确操作氦气检漏仪至关重要。此外,对检漏背后的物理原理及检测过程中的优化可能性了解得越深入,在实际使用氦气检漏仪时就会越得心应手,测量结果也会随之变得更加可靠。 以下综述就如何正确操作氦气检漏仪以及如何在真空系统顺利实施检漏试验给出了一些实用信息。 将检漏仪连接至涂层系统时需考虑的因素 真空系统在调试或维护完毕后产生的渗漏量通常较大。而当渗漏达到某个程度后,市售的氦气检漏仪将无法再继续使用。市售氦气检漏仪的最大工作压力通常约在 6 到 25 mbar 之间。如果产生大量泄漏,该等压力条件可能无法通过抽空过程而达到。图 1 所示的是一个 Si3N4 (氮化硅)涂层系统。可看到,在某次维护后,通过抽空过程仅能将压力降至 80 mbar。有一种方法可降低所用检漏仪的入口压力,那便是使用针型计量阀。 但该方法不仅会导致响应时间延长,而且还必须使用辅助泵。与其对真空检漏仪实施节流调节,我们不妨使用普发真空 ASM 340 检漏仪。此款检漏仪能以定性方式创建一种大规模检漏模式,从而找到当前渗漏所处位置。 以流程泵支持检漏仪 理想情况下,检漏仪应按图 1 和图 2 所示方式连接至真空系统的前真空管线。不过,检漏仪本身适用于洁净环境,而抽空降压过程产生的压缩热会引起严重的热应力,因此,为保护检漏仪,使其免受该等热应力的影响,可能需另行连接一个流程泵。流程泵不仅对热应力不敏感,而且还可抽出所有气体、蒸汽和扬起的颗粒。 另行连接一个流程泵的做法既能提升检漏仪的可用性,还能显著延长检漏仪的维护周期,进而大大降低运营成本。 在抽空降压过程中,一旦压力达到相应的低水平,检漏仪便能一直保持真空。检漏仪中的前级泵功率越大,检漏仪可进一步抽出的气体就越多,真空容器的内表面也就会越大。

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摘要:我们使用太阳模拟器分析了以最高生产率生产硅太阳能电池时可用的测量时间,并阐述了该时间在确定太阳能电池特性所必需执行的不同测量之间的分布方式。针对高效太阳能电池,我们详细说明了“如何减少确定其 IV 特性所需的测量时间以便在所有情况下皆满足生产率要求”。我们发现,通过结合使用电压扫描速度自适应和增强型磁滞评估,可在不牺牲测量精度的同时获得最高生产率,即便对于容量最高的异质结 (HJ) 电池也是如此。 简介 现代太阳能电池生产线生产率极高,生产周期低至 1 秒或不到 1 秒。在不久的将来,单条太阳能电池测试仪和分选机生产线上须实现低至 800 毫秒的生产周期( 相当于高达 4500 片电池/小时的生产率) 。为实现如此短的生产周期,传输和测量时间需满足严格要求。 同时,随着硅太阳能电池效率的不断提高,有效电荷载流子寿命日益变长,使得电池容量不断增大。由此,设备由于工作条件改变后达到准稳态条件所需的时间也随之增加,这是精确测量太阳能电池额定功率的先决条件。在 IV 测量期间,施加的电压从 0 V 变为开路电压甚至更高,即工作条件发生巨大改变。

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由香港中文大学(中大)机械与自动化工程学系副教授卢怡君教授领导的研究团队最近为水系锂离子电池研究了一款新型的电解液,它的材料成本低且不易燃、毒性低、相对环保,更重要的是新型电解液应用到电池中能提供稳定的电压作日常使用,朝改善水系锂离子电池的性能迈进了一大步。研究结果已刊登于国际期刊《自然材料》。 锂离子电池的未来:从易燃有机液到安全水系 全球的经济以及人类的日常生活一直依赖着各类型电子设备,例如手机和笔记本电脑等等,而锂离子电池因为能提供相对稳定的能量,而且可以再充电重复使用,成为了这些可充电式电子产品的核心要素。然而,制造锂离子电池的主要材料之一是有机电解液,即使经过多年改良,这些电解液仍然含有毒性及高度易燃,有机会引发严重的安全问题 — 早年三星Note7手机爆炸、锂离子电池在波音公司787新型客机起火等事故就是其中的例子。 科学界近年深入研究以水系电解液取代传统有机电解液,因水的特质可解决易燃问题。然而,水系锂离子电池一直有个弊病,就是其电池电压和能量密度受到水电解限制。当电压高于1.23伏特,电解液中的水分子便会分解为氢气及氧气,大大影响电池运作及电压输出。增加水系电池电压的新兴做法是利用高浓度锂盐(每公斤21至55摩尔)制造人工固体电极介面及减少自由水含量,以改善水的稳定性,然而这个方法引起了对成本和毒性的忧虑。

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Innovations at the Borssele Wind Farm Site V Climate change and the need to reduce CO2 emissions are drivers for the rising demand of renewable energy sources. With proven experience and an impressive 20-year track record, Van Oord is leading the way in the transition towards renewable energy by constructing offshore wind projects. With innovative solutions, Van Oord contributes significantly to making wind energy more competitive. After two years of preparation, the first monopiles from the Maasvlakte 2 in Rotterdam, have been loaded onto Van Oord’s offshore installation vessel Aeolus and transported to the North Sea. The departure of the Aeolus is the green light for the installation of the foundations for the Borssele 2 offshore wind farm, including the two monopiles for the Borssele wind farm Site V. These two monopiles play an important role in demonstrating innovations for the offshore wind market. The Borssele Wind Farm Site V A new sustainable energy zone is under construction some 20 kilometres off the Dutch coast: Borssele Wind Farm Site V. This site has been designated as an innovation site within the Borssele Wind Farm Zone. Two Towers BV has been awarded the concession and thus given a unique opportunity to test

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In a bid to access stronger and more stable winds, wind farms are moving ever farther from the shore, with current planned projects up to 210km or more out to sea. The challenges associated with increasing wind farm output, however, are many, raising flags at every stage of the wind farm lifecycle. From project delays to overrunning costs, crew safety and even damage to assets, it’s all to play for when the whim of the local environment spells the difference between success and failure. Though it’s true that many unpredictable factors conspire when it comes to weather and wave conditions, by undertaking real-time measurements, performing relevant analyses, and developing appropriate risk assessments, decision-makers can be supported in mitigating - or eliminating altogether - the challenges that come their way. Decision-making support at every step of the way The lifecycle of a wind farm is long. In fact, it can last up to 30 years or more. Within this expansive timeline there are any number of opportunities for leveraging real-time sea state data to drive operational efficiencies and benefit the triple-bottom line. No matter the activity, picking the opportune moment to activate personnel is key, and easy access to real-time, local, environmental data

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In recent years, wind energy has become the main source of renewable energy and it is expected to be the number 1 source of power in Europe before 2030 [1]. By now, thanks to the environmental agreements signed by developed countries and being the drive to address climate change, an exponential increase of wind turbine installations has occurred and much more is predicted in the coming decades. With the rapid change of the wind industry based on the increase of the number of onshore wind turbines together with the take-off of the offshore installations, the requirements for grid integration are getting increasingly demanding [2]. Even if onshore wind power still has a growth margin, the most optimal locations are taken in most countries and now eyes are focused on the sea. The advantage of locating wind turbines offshore is that the wind is much stronger, and unlike onshore, gusts can be strong in the afternoon, matching the time of higher electricity demand. However, offshore installations are more expensive, with difficult access and much harsher conditions than onshore. The optimization of the LCoE (Levelized Cost of Energy) has been the path within the wind industry over the past years [3], highly influenced by the

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Support structures of wind turbines have already been in serial production for a long time. There are now some 1,350 turbines installed in the German North Sea and Baltic Sea alone. The large dimensions, the high dynamic loads, and the specific environmental conditions offshore pose particular challenges and establish the limits of what design codes cover. Despite this, support structures have only suffered minimal serious damage to date, which means that there may still be untapped potential for making these structures even more streamlined. Cost pressures demand that these reserves be quantified more precisely and that potential be identified. Large-scale tests in particular allow the construction and design to be rendered more customized and thus more efficient. Since 2014, large-scale components and parts have been analyzed and tested and, in turn, design bases and approaches validated in the Test Center Support Structures in Hanover. This article summarizes the key findings from recent project work. 1 Developments and trends 1.1 Supporting structures: versions and their potential An end to the growth in the size of wind turbines is not yet in sight. Indeed, leading turbine manufacturers are poised to start producing models in the 10 MW plus class. Increasing hub heights, rotor diameters, and

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