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220ＫＶ系统继电保护及自动装置整定计算 郭世震 220 KV 系统 保护 自动装置 计算

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220ＫＶ系统继电保护及自动装置整定计算 郭世震,220ＫＶ系统继电保护及自动装置整定计算,郭世震,220,KV,系统,保护,自动装置,计算

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华 北 电 力 大 学 科 技 学 院毕 业 设 计（论 文）附 件外 文 文 献 翻 译学 号： 071901010505 姓 名： 郭世震 所在系别： 电力工程系 专业班级： 电气07K8 指导教师： 任惠 原文标题： Investing in expansion:the many issues that cloud transmission planning 2011 年 6 月 15日投资的膨胀1输电线路规划混乱的问题电力是国家的基石，这是由我们国家的经济体系和公民的日常生活决定的。在我们国家的经济中，电力工业约占国内生产总值的4%。在收入方面，它超越了电信，航空，和天然气工业。除了为家庭、商业和工业提供电力，电力行业对当地提供的数以亿计美元的税收，对当地社区的稳定和发展做出了巨大的贡献。通过雇佣近40万的员工以及提供多种多样公共服务方案，来满足于该领域服务当地的需求。这种重要的商品，没有替代品。与大多数商品不同，电力不能够较容易的储存，它必须是在生产的同时就消费掉，所以电力系统必须能满足国家时时刻刻对于电力日益增长的需求。美国西部和东部地区最近的停电强有力的的证明了：电力系统迫切地需要采取有把握的措施确保能继续提供可靠和廉价的能源来保证民族的需求。对该方面的关注很大程度上取决与电力基础设施做出了详细的规划从而满足了经济对于其需要的改变的事实。事实上，对于电力基础设施升级所必要的投资已经达到新低。如图1所示，在20世纪90年代，美国电力供应商的资本开支只占了营业收入的12%，甚至低于在大萧条时期短暂的最低水平。图1：作为电力资本投资的收益百分比（来源：国家能源政策报告，爱迪生电力研究所。）在20世纪50年代和20世纪原文出处及作者：Power & Energy Magazine,IEEEE. Jan-Feb 2004.Shahidehpour, M.60年代，当机械开关和放射性网络设计能够胜任的时候，人们普遍的认为输电系统和配电系统的设计主要是为了工业领域。此外，自1975年以来每年在传输系统的投资已经减少了一半。并且公共设施企业公布的资本开支计划提出资金不足的趋势是不会很快被扭转的。图片2显示了传输系统的扩张是预期增长的四分之一。新的电力输电线路也预计只有6%的增长速度，同未来十年相比在相同的时间段内估计有220%的负荷增长和装机容量的增长。在传输设备上的投资不足带来了消极的后果，包括更高的拥堵成本；更频繁的经济交易的缩减；增加能量损耗；更高的传输系统维护费用；更频繁的传输相关的服务中断。增加了在水平电力市场的运行机会，甚至是在相对缺乏的垂直电力市场。最近在美国和欧洲发生的事件证明对与输电系统的纯粹的社会花费不足，由于这种随时变化的传输能力不足，可能会成为超过成本的过度投资，甚至会使得消费成本大幅增加。在对传输进行规划的规划人员看来，有几个原因造成了在过去十年对与传输基础设施投资的不足，这也会成为未来十年这种不足的原因所在。l 基于对能源政策、传输所有权和执行令人气馁的电力传输新规划的长时间的不确定性。l 市场参与者包括传输公司在内的商人主要关注商业机会和传输与能源的营销。l 大部分对于传输的投资很难向州监管部门证明其正确性。因为在一个广阔的地区当本地实用的客户将支付成本的主要份额时，在传输上的投资在往往会有很多收益。l 重组后的电力系统的能源价格要胜于零售能源的价格，这已使得传输设备公司难以收回他们的投资成本。l 目前在规划充足和可靠的基础传输设施方案没有在电力行业建立选区。图2：投资于新的带那里传输。用电高分需求的增长已远远超过对输电能力的投资。 因此，电力传输的限制可能加剧本已有限的电力供应和导致在国家的某些地区的价格。（来源：PA咨询团队，基于UDI的数据库中的数据。）以输电线路的系统规划为例在输电线路的竞争舞台上有各种各样的障碍。首先，输电成本只有发电成本的十分之一，所以如此显而易见的问题是他们为什么没有建立足够多的传输设施从而使他们永远不2会限制发电市场。这个简单的规划方法主要是呼吁那些更偏爱与设计满足意想不到的负荷需求的超额定容量系统的电力工程师和那些打算在大区域内展开贸易的市场参与者。然而现实是建设新的输电线路往往被当地居民和土地所有者所反对，因此在政治上难以实现。此外监管规则可能不允许公共事业设施快速的收回这种过度建设的花费。此外以市场的力量可以忽视掉供给可靠性的公共价值为基础的输电计划。这样的计划也忽视了把输电线路通过链接联合起来扩大当地居民的利益。原则上规划者之间的协议在增加，长期来讲一些以市场为基础的计划形式，以及与成对的物质基础，管理的远景构画，公众的利益是至关重要的。这种以市场为基础的途径将会为投资者提供关与新的生产项目在哪里选址的意见，有助于系统规划者、监管者和地方当局决议和通过对与输电的规划和选址。下面这一部分则是一些对输电系统的选址和规划更深入的辩论。区域输电规划从历史上看，发电和输电被由国家监管下的垂直整合规划成为一个完整的标准。模型、数据、分析和传输计划相应的使地区准则与满足可靠性的目的相协调。在这个过程中遇到了发电与负荷相平衡的主要目标，但是没有涉及到促进电力市场的竞争性的次要目标。大家都注意到传输行为是在自然区域，因此规划过程也应该具有区域性。正如公路和机场适应区域需求，输电规划应通过区域输电组织（RTO）。之前所说的并没有禁止当地的投入，然而国家、地方政府和地区产业能够并且也应该在规划以及扩大传输设施方面寻求合作。联邦政府的作用根据现行法律，输变电设施的选址是国家政府的责任，即使传输系统不仅是州与州之间还涉及到国际，延伸到加拿大和墨西哥。近80年前写于1935年的联邦法律规定了政府对输电设施的选址负责。当时并没有洲际输电设施，而且在当时也几乎没有洲际输电贸易。一般来说州政府在输电线路的选址方面经常意识不到规划输电线路对与洲际输电网络的重要性。因此，联邦能源管制委员会可能对洲际输电线路的建设和选址产生重大的影响。例如，目前在传输选址方面的瓶颈是获得有限的通行权。联邦政府是美国最大的地主，在西部的某些地区拥有大量土地。通过改进使用联邦土地的权利，能帮助消除一些输电线路规划的约束条件。另外，限制电网规划的问题在于缺乏一个具有强制性的可靠性标准。1968年以来，美国的电力传输网的可靠性完全取决于自愿遵守的标准。一个普遍承认并且自愿遵守的可靠性标准已不再是在一个竞争日益激烈的电力市场下的可行办法。因此，2003年在美国东北部的突发事件中，已经显示出了在联邦能源管制委员会监督下的自律组织对发展和改进这些标准的广泛的支持。最近电力行业努力为获得政府批复兴建新建的输电线路或是升级现有的输电设施，而这些经常是有争议的。同时传输系统迫切地需要改进与提高。州政府、联邦政府和输电传输的所有者为了做出有效地改变而更密切的合作，以改进传输项目的审批过程，继续尊重和保护受影响的所有输电工程各方的合法权益。3输电基础设施的成本不建设输电线路的间接成本，如消费者为许多没有使用权的电力来源买单，以及对于停电所付出的经济损失。这些成本可以同直接建设和运行一条输电线路的成本同样重要。当决定建设一个新的输电线路时间接成本必须考虑在内。由于美国的电力系统扰动的经济损失远远高于预期，并已成为美国经济具有重要意义。亏损就代表了对于电力行业每花一美元就要多花费约50美分的额外费用。除了直接成本的干扰，许多高科技公司需要优质的电力并且他们正安装越来越多现场设备已满足他们的特殊需要。在越来越多的案例中，在建筑物中安装功率调节设备成本已经开始主宰的电力输送成本。由于法律部明确周边的电力传输和布局规划，大部分公司都已经限制了他们的投资，直到建立起更完善的市场结构。投资几乎被完全限制在完成的项目即正在建设的项目或是为取消订单而支付的罚款。依照目前的法律规定，环境投资被限制在一般而言的最低水平。在未来的二十年更密集的输电规划和技术的实施，可以减少干扰的频率和可能的损失，都够保守地降低一半的断电成本。若不采取降低电源干扰的措施，可能导致电力基础设施的近一步恶化，或许导致在二十年的周期里每年有1000亿美元的成本增加。宣传和公共教育建一条新的传输线已经比建一个新的发电厂困难的多。新的电厂占地面积比较小，并且可以被放置在反对声最小的地方。然而，输电线路规划者在其有限的选择权利内，选择现有的系统配置的方式，优先发展，以及环境和土地的使用问题。当涉及到传输附件时，几乎任何一个多样的政治行政辖区内沿着规划的路线可以延迟甚至否决掉该议案，这些有效的阻止了规划的提议。在这些时间中，在联邦或州一级的政治实体往往拒绝接受一个广大公众利益的观点而优先考虑地方对该提议的反对。公众支持输电系统的关键在于公众对输电线路工程的认识，这可能会影响许多从不能从输电线路工程中看出什么直接利益的人。对项目的公开和坦诚的讨论，项目的优缺点以及业主在建设和运营输电线路事的责任能够进一步加深对其的认识和理解。增加输电和发电的容量先进的能源管理系统为控制传输电流和电压提供了新的可能，并会顾及到系统的拓展能力，而不需要在短期内去新建工程。其中为改善输电网的控制和稳定的电力电子器件的各种新的硬件设施是用于管理传输电流的超导和低成本直流连接以及灵活交流输电系统（FACTS）。规划工具可以无缝的整合本地的已安装的和可再生的发电设备（如燃料电池、太阳能、风能、小水电机组、微型燃气汽轮机）这样可以减少电力传输和分配的需要。新一代的技术从煤炭的提炼、联合循环机组和以先进的核电厂也可以形成一个廉价的并且对未来清洁的能源的核心。管理传输基础设施的创新技术与目前输电设施的投资环境形成对比的是对于新技术的应用的研究而言，输电基础设施的前景从来没有光明过。然而新的政策迫切地需要放开能够把电力系统转变为更具有企4业性的新技术的研究，这样可以更好地服务于我们不断增长的社会需求。一个突出的应用技术是创造一个充满活力和相互作用的电力系统，这是电力网络与通信网络的合并，形成实时信息和电力基础设施的交换。这种新的基础设施将需要授权与能源零售市场，支持控制中心之间的互动，管理电力系统敏感元件的安全性，并且从根本上提高电力的价值。这还将促进在消费者水品管理负荷以及将电力系统转变成一个消费通道，这个通道允许价格信号、决策和沟通通过能源/信息的双向门户来双向流通。公众对功能的改造和提升电力服务价值的支持可能是有道理的，因为社会从更有效的利用能源中节约的款项将大大超过新技术的额外费用。最后一点在美国大约有157810英里的输电线路，而输电线路的扩张预计在未来的十年慢下来，合计只有7000英里。关键的问题是经济和电力基础设施之间的巨大缺口正在逐渐变大，这应该被期望支持经济发展。扩大传输系统会同过减少中断的可能性来使消费获益。促进负担的起的和稳定的电力价格，鼓励采用洁净的能源建设更高效的电厂。虽然平均输电成本代表了一小部分的交付的电力总成本，任何电力传输投资具有远远超过花费的潜在的生产效益。拓展阅读1. “通信和电力系统的控制，”M. Shahidehpour and Y. Wang，纽约：Wiley数据库，2006年6月。2. 电力部门对未来的框架，电力科学研究院出版，Palo Alto，硅谷，2003年。3. 电力系统市场运作，M. Shahidehpour, H. Yamin, and Z.Li,纽约：Wiley数据库，2002年3月。4. “确保在竞争性的市场下的电力传输扩张，”美国输电公司出版社，Waukesha，维斯康星州，2002年。5. “美国未来的可靠、价格适中并且对环境无害的能源，”国家能源政策发展小组报告，华盛顿特区，2001年。6. “美国未来的电力传输，”PA咨询出版物，纽约，2001年。7. “问题及解决方案：北美电网规划，”电力科学研究院出版，Palo Alto，加利福尼亚州，2000年。8. “美国电力行业结构改组后充足的发电和输电，”爱迪生电气协会出版社，华盛顿特区，1999年。514IEEEpower & energy magazinejanuary/february 20041540-7977/04/$20.002004 IEEEEELECTRICITY IS A CORNER-STONE on which the economy and thedaily lives of our nations citizensdepend. In our nations economy, theelectric power industry representsapproximately 4% of the gross domes-tic product (GDP). In terms of revenue,it surpasses industries such as telecom-munications, airline, and gas. In addi-tion to providing electricity to homes,businesses, and industry, electric powercompanies are major contributors to thegrowth and the stability of local com-munities across the nation in the formof billions of dollars in tax revenues, byemploying nearly 400,000 workers,and by providing a variety of publicservice programs that address the localneeds of the areas they serve. Thisessential commodity has no substitute.Unlike most commodities, electricitycannot easily be stored, so it must beproduced at the same instant it is con-sumed. The electricity system mustaccommodate the nations ever increas-ing demand for electricity every secondof the day and every day of the year. The recent blackouts in the Westernand Eastern regions of the UnitedStates provide growing evidence thatcertain actions are urgently needed toensure that the electricity sector willcontinue to meet the nations needs forreliable and affordable energy. Much ofthe concern in this respect is due to thefact that the electricity infrastructurehas made minute provisions to meet thechanging needs of the economy. In fact,the investment needed to upgrade theinfrastructure has reached new lows. Asshown in Figure 1, capital expendituresby U.S. electricity providers were onlyabout 12% of revenues during the1990s, which is even below the levelreached briefly during the Depression. It is widely believed that the currenttransmission and distribution systemswere designed primarily for the indus-trial era of the 1950s and 1960s, whenmechanical switching and radial net-work design were adequate. Further-more, annual investment in the trans-mission system has been cut in halfsince 1975, and capital expenditureplans announced by utility companiessuggest that the under-funding trend isnot going to be reversed soon. Figure 2shows that the expansion of the trans-mission system is roughly one-quarterof the projected growth in demand.The construction of new transmissionlines is projected to grow by only 6%Mohammad Shahidehpourthe busines sceneinvesting in expansionthe many issues that cloud transmission planningARTVILLEAuthorized licensed use limited to: NORTH CHINA ELECTRIC POWER UNIVERSITY. Downloaded on February 25,2010 at 05:09:53 EST from IEEE Xplore. Restrictions apply. over the next ten years compared to anestimated 20% increase in load growthand installed generating capacity overthe same time frame.Under-investment in transmissionfacilities has had negative consequences,including higher congestion costs andmore frequent curtailment of economictransactions, increased energy losses,higher transmission system maintenancecosts, more frequent transmission-relat-ed service interruptions, and increasedopportunities for the exercise of hori-zontal market power, even in theabsence of vertical market power. Therecent events in the United States andthe Europe proved that the net socialcosts of under-investment in transmis-sion could exceed the cost of over-investment due to a substantial increasein consumer costs incurred from evenminute transmission capacity shortages.Among transmission planners, it is per-ceived that several factors have con-tributed to this under-investment intransmission infrastructure over the pastdecade, including the following.An extended period of uncertain-ty over energy policies and trans-mission ownership and operationhas discouraged the planning fornew transmission facilities.Market participants includingtransmission companies havefocused primarily on businessopportunities in merchant gener-ation and transmission and ener-gy marketing.figure 1. Captial invested as a percentage of electricity revenues. (Source:National Energy Policy Report and Edison Electric Institute.)60%50%40%30%20%10%0%GenerationTransmissionDistribution19251930193519401945195019551960196519701975198019851990199520002005201020152020Authorized licensed use limited to: NORTH CHINA ELECTRIC POWER UNIVERSITY. Downloaded on February 25,2010 at 05:09:53 EST from IEEE Xplore. Restrictions apply. Major investments on transmis-sion are often difficult to justifyto state regulators since much ofthe benefits are to accrue over awide region while the customersof the local utility will be payingthe major share of costs.The cap on retail energy rates inrestructured power systems hasmade it difficult for transmissioncompanies to recover theirinvestment costs.There has been no established con-stituency in the power industry forthe planning of adequate and reli-able transmission infrastructure.The Case for TransmissionSystem PlanningThere are various obstacles for trans-mission planning in a competitivearena. At the outset, transmission costsonly one tenth as much as generation,so the obvious question to ask is whydont they build enough transmissionso that it would never constrain genera-tion markets? This simple planningapproach is mostly appealing to powerengineers who prefer systems withexcess capacity to meet unexpectedneeds and to market participants whointend to trade power over largeregions. However, the reality is that theconstruction of new transmission linesis often opposed by local residents andlandowners and is therefore politicallydifficult to achieve. In addition, regula-tory rules may not permit utilities torecover fully the cost of such overbuiltsystems. Furthermore, transmissionplans based on market forces couldneglect the public value of providingadequate reliability. Such plans couldalso ignore the need to link any trans-mission expansion proposals to localcustomer benefits. In principle, agree-ment among planners is growing thatsome form of market-based planningcoupled with physical constraints, reg-ulatory perspectives, and public inter-ests is essential in the long term. Suchmarket-based approaches will providesignals to investors on where to locatenew generation and will help systemplanners, regulators, and local authori-ties decide and agree on transmissionplanning and siting.In the following sections are a fewitems that could be debated further onthe planning and siting of electricitytransmission facilities.Regional Transmission PlanningHistorically, generation and transmis-sion were planned on an integratedbasis by a vertically integrated utilityunder state regulatory oversight. Mod-els, data, analyses, and transmissionplans were accordingly coordinated ona regional basis for reliability purposes.This process met the primary objectiveof balancing generation with load butdid not address the secondary objectiveof facilitating competitive electricitymarkets. It is well noted that transmis-sion operation is regional in nature, sothe planning process should be regionalas well. Just as highways and airportsadjust to regional needs, power trans-mission planning should be through theregional transmission organization(RTO). This premise does not ban localinput; however, states, local govern-ments, regional industries, and the pub-lic can and should collaborate on theexpansion and planning of transmissionfacilities. Role of Federal GovernmentUnder current law, the siting of powertransmission facilities is a responsibili-ty of state governments, even thoughthe transmission system is not onlyinterstate but also international, extend-ing into both Canada and Mexico. Fed-eral law governing the responsibilityfor siting transmission facilities waswritten in 1935, nearly 80 years ago. Atthe time, transmission facilities werenot interstate, and there was virtuallyno interstate commerce in electricity. Ingeneral, state decisions on where tolocate transmission lines often do notrecognize the importance of proposedtransmission facilities to the interstategrid. Hence, the FERCs role couldhave a major impact on siting and con-struction of interstate electric transmis-sion lines. For instance, a currentbottleneck in transmission siting is thelimited access to right-of-way. The fed-eral government is the largest landown-er in the United States and owns mostof the land in some Western states.Improved access to federal land canhelp remove some of the transmissionplanning constraints. Also, a limiting transmission planningissue is the lack of enforceable reliabilitystandards. Since 1968, the reliability ofthe U.S. transmission grid has dependedentirely on voluntary compliance withreliability standards. There is a broadrecognition that voluntary adherence withreliability standards is no longer a viableapproach in an increasingly competitiveelectricity market. Accordingly, the 2003contingencies in the Northeastern part ofthe United States have emerged broadsupport for the development of thesestandards by self-regulating organizationsoverseen by FERC. Recent electricity industry effortsto obtain government approval toconstruct major new transmissionfacilities or upgrade existing facilitieshave frequently been controversial.At the same time, the need for trans-mission system improvements growsurgently. State and federal govern-ments and transmission owners needto work more closely for making sig-nificant changes to improve theprocess of reviewing and approvingproposed transmission projects whilecontinuing to respect and protect thelegitimate interests of all partiesaffected by transmission projects.Cost of Transmission InfrastructureIndirect costs of not building transmis-sion lines, such as the price consumerspay for not having access to manysources of electricity and the economiccost of blackouts, can be just as impor-tant as the direct construction and oper-ation costs of a transmission line. Theindirect costs must be factored in whendetermining whether to build a trans-mission line. The financial losses due toU.S. power system disturbances aremuch higher than expected and havebecome significant to the U.S. econo-16IEEEpower & energy magazinejanuary/february 2004Authorized licensed use limited to: NORTH CHINA ELECTRIC POWER UNIVERSITY. Downloaded on February 25,2010 at 05:09:53 EST from IEEE Xplore. Restrictions apply. january/february 2004IEEEpower & energy magazinemy. The loss represents an additionalcost of about 50 cents for every dollarspent for electricity. In addition to thedirect costs of disturbances, many high-tech companies need perfect power andincreasingly they are installing on-siteequipment to meet their specializedneeds. In a growing number of cases,the cost of installing power condition-ing equipment in buildings has begun todominate the cost of power delivery.Due to the regulatory ambiguitysurrounding transmission and distribu-tion planning, most companies havelimited their investments until the mar-ket structure is established more clear-ly. Investments are almost completelylimited to completing the projects thatare under construction or to payingpenalties for canceled orders. Environ-mental investments are being limitedin general to only the absolute mini-mum that current laws require. A more intensive transmission plan-ning and the implementation of technolo-gies over the next two decades that canreduce the frequency of disturbances andpossible damages should conservativelyreduce outage costs by about half. Failureto take action to reduce power distur-bances could result in further degradationof the electricity infrastructure, leading toan increase in costs, perhaps by as muchas an additional US$100 billion per yearover a 20-year period.Outreach andPublic EducationIt has become considerably more diffi-cult to construct a new transmission linethan a new generating plant. New gener-ation has a small geographic footprintand can be sited in areas of minimalopposition, whereas transmission plan-ners are limited in their choice of rightsof way by the existing system configura-tion, prior development, and environ-mental and land use issues. When itcomes to transmission additions, virtual-ly any one of the multiple political juris-dictions along the planned route candelay or even veto the plan, whichwould effectively block the planning ini-tiative. In such incidents, political enti-ties at the federal or state level haveoften refused to take a broader publicinterest perspective by preempting localoppositions. A key to the public supportof a transmission planning project is thepublic understanding of a transmissionline project, which can affect many peo-ple who may not see any direct benefitsfrom the transmission line. Open andfrank discussion of the project, its bene-fits and drawbacks, and the ownersresponsibilities in building and operat-ing the transmission line will furtherhelp that understanding.Enhancement of Transmissionand Generation CapacityAdvanced energy management systemsoffer the hope for controlling transmis-sion flows and voltages and will allowfor expanded capability on the systemwithout requiring new construction inthe short term. Among the new hard-ware facilities for managing transmis-sion flows are superconducting andlow-cost dc connections as well as flex-ible ac transmission system (FACTS)devices, which refer to a variety ofpower electronic devices for improvingthe control and stability of transmissiongrid. Planning tools could seamlesslyintegrate an array of locally installeddistributed and renewable power gener-ation (such as fuel cells, photovoltaic,wind, small hydro units, microturbines),which could reduce the need for trans-mission and distribution. New genera-tion technology ranging from coalrefining, combined cycle units, toadvanced nuclear power plants couldalso form the core of a clean and afford-able energy portfolio of the future. Innovative Technologies forManaging TransmissionInfrastructureIn contrast to the current investment cli-mate for transmission planning, theprospects for the application of newtechnologies to transmission infrastruc-ture have never been brighter. New poli-cies, however, are urgently needed forunleashing innovative technologies thatcould transform electric power systemsto an enterprise that could better servegrowing demands of our society. Aprominent application of technology is tocreate a dynamic and interactive powersystem that is merged with communica-tion networks to form a real-time infor-mation and power exchange17figure 2. U.S. investment in new electric power transmission. Growth in peakdemand for electricity has far outstripped investment in transmission capaci-ty. As a result, transmission constraints could aggravate already limited suppliesof power and could result in high proces in some areas of the country. (Source:PA Consulting Group, based on data from the UDI database.)U.S. Investment in New Electric Power Transmission(Millions of 1990 Dollars)1990199119921993199419951996199719981,4001,20080060003103002902802702600Transmission InvestmentSystem Peak DemandAuthorized licensed use limited to: NORTH CHINA ELECTRIC POWER UNIVERSITY. Downloaded on February 25,2010 at 05:09:53 EST from IEEE Xplore. Restrictions apply. infrastructure. This new infrastructurewill be needed to empower retail energymarkets, support the interaction amongcontrol centers, manage the security ofsusceptible components of the powersystem, and fundamentally raise thevalue proposition for electricity. It willalso promote the load management at thecustomer level and transform