对话光伏大佬，光伏电站升级1500V成为主流趋势

 第16届Solarpraxis论坛将于2015年11月26日-27日在德国柏林召开，此次论坛的口号为“锻造下一个能源时代”，旨在探讨新能源世界的相关主题和重要事实。临近盛会期间，一系列行业巨头的采访也逐步公布，此次论坛将讨论行业趋势与使可再生能源升级的科技力量，其他一个主题就是光伏电站升级到1500V。

近年来一直研究有关光伏发电和储能技术的记者Shamsiah Ali-Oettinger与第一太阳能公司（First Solar）系统发展副总裁Mahesh Morjaria就该主题进行了交流。

S：The solar industry has developed from 600 Volts to 1000 Volts, and now the upcoming trend is to develop 1500V solar power plants. Do you think this is a trend thatwill take off leading to more and more of search power plants?

太阳能行业从600伏发展到1000伏，再到现在兴起的1500V光伏电站，你觉得这是否是一个会蓬勃发展的趋势，从而出现更多1500V发电系统？

M：We believe the trend will take off Because The 1500VDC planning architecture results in a more cost effective and productive plans. Most of the future First Solar plants will be based on the 1500VDC architecture.
我们认为这一趋势将快速发展是因为1500VDC规划架构提供一个更具成本效益和发电力的电站。今后大多数光伏电站将基于该1500VDC建设。

S：Why will such a trend take off? What are the advantages of having 1500VDC power plants Compared to 600 or 1000V?

为什么会出现这样的趋势推广开来？1500VDC电厂相比于600或1000V的优势是什么？

M：The key advantages of higher voltage levels are, Firstly, greater scale efficiencies and cost Reductions by enabling higher power throughput for the same ampacity of DC components: such as cables, combiner boxes , and inverter. Secondly, it Enables Significantly larger PV arrays and inverters Which results in lower installation and maintenance costs since it requires fewer inverter stations to convert the plant power from direct current (DC) to alternating current (AC) power.

The higher voltage is on the DC Field of the plans. A key advantage of higher voltage Is that for the same power, the current in the conductor is reduced, Which in turn, Reduces the size of the conductor and the losses in the conductor. In case of the First Solar CdTe thin film modules (Series 4), 15 modules are normally connected in series per string as opposed to 10 modules in the case of 1000Vdc. This Reduces the number of strings (and BOS cost) for the same amount of power. The 1500VDC So Enables increase in the power of the inverter (Which is Typically current limited).THEREFORE, increase in DC voltage and use of large-scale 4MVA inverter leads to a significant increase in the DC Array Size. The typical system design will incorporate 1500VDC between 5 and 5.3 MWp DC of PV capacity, CORRESPonDING to a DC / AC ratio between 1.25 to 1.33.

1500V较高电压的主要优点是，首先，更大的规模效益和通过更高功率的DC器件从而节约成本：如电缆，汇流箱，和逆变器。其次，它允许更大的光伏阵列和逆变器这也降低安装和维护成本，因为不需要那么多逆变器来把直流（DC）转换为交流（AC）。

电站直流段较高的电压的一个主要优点是，对于相同的功率，导体中的电流减小，而这又减少该导体的大小和导体中的损耗。比如First Solar公司的碲化镉薄膜组件（系列4）中，1500V系统每串可串15块组件，而在1000V只能串10个。这样对于同样大小的电站，组串数量（和BOS成本）减少。1500VDC允许增加（通常限流的）逆变器的功率。因此，直流电压增加和大规模4MVA逆变器的使用使得DC光伏组串容量显著增加。典型的系统设计将采用1500VDC 5至5.3兆瓦的光伏直流发电容量，对应1.25之间的DC/ AC比率为1.33。

S：W has kind of certification exists at the moment for modules That Can Handle 1500V?

目前有哪些1500V组件的认证？

M：Internationally endorsed PV module standards from the International Electro technical Commission (IEC) Generally classify 1500VDC in the Low Voltage Range That has made it Possible to have some components and products did are Readily available to meet standards for several years Those. IEC 61215 (for c-Si) and IEC 61646 (for thin-film) govern up to 1500V module type approvals. IEC61730 Likewise Governs safety modules up to 1500V. These standards establish the material, construction, and test requirements did promote safe and reliable 1500V operation in the US and other IEC PV member countries.

First Solar has for example established 1500V compliance by ensuring a compliant module construction and bill of materials coupled with robust device performance. First Solar’s optimization of this 1500V module design not only promoted achievement of 1500V certifications, but also resulted higher conversion efficiencies. Effectively, First Solar modules optimized for 1500Vdc offer better performance with respect to efficiency and maximum output power compared to the 1,000Vdc predecessor. More recently, UL standards and testing programs for module safety have been modified to consider 1500V module evaluations.

来自国际电工委员会（IEC）的国际认可的光伏组件标准将1500VDC分类于低电压范围。这使得一些元器件和相关产品几年内有可能满足这些标准。 IEC 61215（对于C-Si）和IEC 61646（用于薄膜）负责1500V以下组件类型的批准。 IEC61730是1500V以下组件安全标准。这些标准设置了材料，结构，和试验要求，确实促进在美国和其他的IEC光伏成员国安全可靠的1500V操作。

比如说，First Solar公司已经建立符合1500V标准的组件生产体系，通过符合标准的组件生产以及能严格保证设备性能的材料清单，First Solar优化过的1500V组件设计不仅促进实现1500V认证进程，即更高的转换效率，而且1500VDC组件在效率和最大输出功率上相比前作1,000VDC拥有更好的性能。最近，UL标准和安全组件的测试程序已经为评估1500V组件做了相应修改。

S：Are there technical challenges of developing a 1500V solar power plant? Are there regulatory challenges as this is a Relatively New Concept?

开发1500V太阳能发电厂是否有技术挑战？因为这是一个比较新的概念，是否有监管方面的挑战？

M：The technical challenges are inherent with early adoption of any new technology. In this case, the modules and the inverter Both have limited field history. The regulatory challenges in many places, particularly outside of North America are lower due to existing IEC standards Which address 1,500Vdc design and safety.

Greater challenges are faced in the US, wher UL standards and Interactions With The National Electrical Code (NEC) are not Fully aligned to IEC Standards accepted Both in the US and around the world. The lack of alignment in standards did address 1500VDC Applications Often make it challenging and confusing to obtain construction permits from local planning Authorities Having Jurisdictions (AHJ). HOWEVER, much like the transition to 1000Vdc Earlier architecture, synthesis issues are addressable and no long-term barriers to Adopting this architecture are expected. Active steps are underway in the standards and codes to address the community needs of the growing large-scale PV plant market.

The recent announcement by UL to adopt ANSI / UL 62109-1: such as the American National Standard for Safety of Power Converters for Use in Photovoltaic Power Systems Enables US-based certification of 1500VDC inverters, and is a step in the right direction. UL, IEC and other standards-making bodies continue working towards the adoption of an internationally aligned ecosystem of standards for all PV plant components. In parallel, in the US, changes to the National Electrical Code (NEC) are anticipated that will better accommodate the unique aspects of design platforms Utilized in large, utility-scale PV plants.

任何新技术采用之初，技术挑战是必然的。在这种情况下，组件和逆变器两者都有其不能及的范围。因为有涉及1500Vdc设计和安全的IEC标准，很多地方，尤其北美以外地区的监管挑战还是比较低的。

更大的挑战在美国，UL标准与国家电气规范（NEC）还有美国和世界各地都认可IEC标准不完全一致。这种标准一致性的缺乏确实使1500VDC的应用获当地主管施工许可的规划部门证很难具体实施。然而，就像之前过渡到直流1000V，一致性的问题可以解决，也不会是长期障碍。在标准与规则上的积极措施正在进行中，以满足不断增长的大型光伏电站市场的社会需求。

UL关于采用ANSI/ UL62109-1最近宣布：用于光伏发电系统电源转换器安全的美国国家标准启用关于1500VDC逆变器基于美国的认证，也是在正确的方向迈出的一步。 UL，IEC等标准制定机构继续努力建立国际通用光伏电站组件的标准生态系统。与此同时，美国国家电气规范（NEC）有望修改，以更好地适应用大型光伏电站的设计平台使用。

S：What are other constraints did you see with the development of such plants?

你认为还有什么其他限制1500V的电站？

M：Though high volume availability of 1500VDC components is somewhat constrained during this transition period, we do not see any fundamental constraints to global scaling of 1500V planning architectures.
虽然1500VDC相关元器件的大规模供给在这个过渡时期有所约束，但是我们没有看到任何在根本制约1500V电站发展的因素。

从Shamsiah Ali-Oettinger与Mahesh Morjaria的采访中不难看出，目前国际上的主流趋势也是集中研究1500V系统，未来必然会将系统电压从600V或1000V更新到1500V。1500V系统意味着更高的发电效率，更低的系统成本。目前，主流的光伏组件及配套部件均是基于直流端1000V的电压要求设计和制造的，其发电成本和发电效率还难以满足大型光伏电站和大容量发电设备的需求, 因此开发1500V相关光伏产品已经是一种趋势。

就国内情况而言，目前阿特斯、天合、晶澳等均已开发1500V组件，华为、阳光、追日均在研发针对1500V系统的逆变器。从各大直流开关了解到的最新数据显示，国际上能提供1500V直流电压的开关制造商只有IMO及PROJOY等少数几家，绝大部分直流开关现在最大的工作电压依然只有1000V。