About Parallel Capacity (N) And Parallel Redundancy (N+)

Uninterruptible power supplies operating in parallel refers to when the outputs of two or more UPS are connected to supply the load via a common AC busbar.  

不间断电源并机运行的是指将两个或多个 UPS 的输出连接起来，通过公共交流母线为负载供电。

There are two main configurations: 

并机运行主要有两种配置：

1, Parallel-Capacity (N) where the total load demand is met by a number of UPS without the provision of any redundancy

2, Parallel-Redundant (N+X) where the total load demand is met by all the UPS sharing the load between themselves equally. If one of the UPS fails, the remainder are able to continue supporting the load.  

1，并机容量 (N) ，其中总负载需求由多个 UPS 满足而不提供任何冗余

2，并机冗余 (N+X)  ，其中所有 UPS 均等地分担负载来满足总负载需求。如果其中一台 UPS 出现故障，其余 UPS 能够继续支持负载

Parallel-Capacity (N) UPS Systems

‘N’ configuration solutions do not increase system resilience because they lack redundancy, they simply enable increased overall capacity by connecting multiple UPS to work together. The total capacity is calculated by the number of UPS modules used (also known as a Total Power System). 

Because of the lack of redundancy, carrying out maintenance on a parallel-capacity installation means bypassing the entire UPS system so that one or more modules can be powered down for service. During UPS maintenance, the load is powered directly by the mains supply, so it is unprotected to any interruptions.

The below image shows a parallel-capacity 45 kVA power system comprised of three 15 kVA UPS operating at 100% load.  

并机容量 (N) UPS 系统

“N”配置解决方案不会增加系统弹性，因为它们缺乏冗余，它们只是通过将多个 UPS 连接在一起工作来增加整体容量。总容量由使用的 UPS 模块数量（也称为总电源系统）计算得出。

由于缺乏冗余，对并机容量安装进行维护意味着绕过整个 UPS 系统，以便可以关闭一个或多个模块进行服务。在UPS 维护期间，负载由市电直接供电，因此不受任何中断保护。 

下图显示了由三个 15 kVA UPS 组成的并机容量 45 kVA 电源系统，在 100% 负载下运行。  

Parallel-Redundant (N+X) UPS Systems

‘N+X’ configuration solutions are commonly used to protect mission-critical applications in data centres, industrial sites and larger business operations. The main principle behind a parallel-redundant UPS system is that it can continue to support the critical load should one or more UPS modules fail. Compared to N capacity installations, this means it can achieve higher availability and MTBF (mean time between failure). 

In addition, this also enables UPS maintenance to take place without interrupting the load. Modules can be powered down for servicing while the remaining UPS continue supporting the load. 

The below image shows a parallel-redundant 30 kVA N+1 power system comprised of three 15 kVA UPS equally sharing the load (10 kVA per UPS). 

并机冗余 (N+X) UPS 系统

“N+X”配置解决方案通常用于保护数据中心、工业站点和大型企业运营中的关键任务应用程序。并机冗余UPS 系统背后的主要原则是，如果一台或多台 UPS 出现故障，它可以继续支持关键负载。与并机容量 (N) 相比，这意味着它可以实现更高的可用性和平均故障间隔时间。

此外，这还可以在不中断负载的情况下进行 UPS 维护。单台UPS可以断电进行维修，而剩余的 UPS 继续支持负载。

下图显示了一个并机冗余 30 kVA N+1 电源系统，它由三个 15 kVA UPS 组成，平均分担负载（每个 UPS 10 kVA）。 

During normal operation, each UPS shares the load equally. Similarly, when the UPS system needs to run on batteries, each UPS will still share the load as each module has its own battery set, rather than a shared common battery. 

If any of the UPS modules in a parallel-redundant configuration fails or experiences an internal fault, it automatically disconnects from the output AC busbar, while the remaining active UPS continue sharing the load. 

在正常运行期间，每台 UPS 均分负载。同样，在逆变模式下，每台UPS 仍将分担负载，因为每台UPS都有自己的电池组，而不是共享电池组。

如果并机冗余配置中的任何一台UPS 出现故障，它会自动断开与输出交流母线的连接，而剩余的活动UPS继续分担负载。

Foshan Unipower Electronic CO.,LTD

19 years of experience in developing and manufacturing UPS, inverter and AVR products. 

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Tel:86-757-82962332/86-757-82782286

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Email:sales@svcpower.com

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