·Application Fields:

■Communication systems;

■Financial systems;

■Industrial automation systems;

■Internet Data Center (IDC);

■Media Data Center (MDC);

■Other key load system.

·Characteristics:

■Industrial design: standard 19-inch black cabinet;

■Maintainability: online hot-plug, no need to switch to the bypass;

■Expandability: to achieve online capacity expansion, online upgrade, online maintenance;

■Green energy-saving: high efficiency, low heat loss, pollution-free for the electrical power network;

■High cost-effective: reducing the initial purchase costs and future cost of capacity expansion, maintenance and operation for the users;

■High reliability: solving the single point fault bottleneck to provide the reliable supply protection for the key load;

■High anti-interference: it can eliminate the "power supply interference" as much as possible whatever it is from the main power or UPS itself that include conducted interference and radiated interference.

·Dual Bus Modular (N+X) Solution Description:

The internet data center (IDC) and media data center (MDC) are the regulation and control centers of high-speed internet. Users have an ultra-high demand for their timeliness of remote processing, storage and transmission for information resources (data, voice and image).

Just a few seconds of the "stop" will bring the immeasurable losses for the safe operation of entire Internet and operation of users. What's worse, it can cause the serious damages for the social and economic activities. Therefore, the IDC must provide value added services of information resource featured as continuous high-speed for 365×24 hours, safe and reliable.

For this purpose, from the perspective of design principle, the whole power supply system of IDC has to adopt redundant power supplying solution of high "fault-tolerance" function to ensure that whatever the main power electrical network or inverter of "double-conversion online UPS " fails and fuse burns out orthe breaker trips the inverter of online type UPS will supply the power to the internet devices, it shouldn't be powered by main power or emergency backup generators through AC bypass. Because only inverter of online UPS is likely to provide the load of users with high-quality sine power with both stable voltage, non- frequency discontinuity, non-interference, minimum waveform distortion.

For the off-line UPS including backup UPS and online interactive UPS, they mainly adjust the voltage of input power supply and do not "substantively" improve the frequency jitter of input voltage, all kinds of supply interference and voltage distortion. That means there is no "bottleneck" fault risk in the whole power supplying system, so it must be configured with UPS redundant power supplying system of the high "fault-tolerance" function. In other words, even if some "components" occasionally fails during the operation of UPS power supplying system, the whole UPS power supplying system must still be able to run as usual.

Compared with the traditional UPS, the UPS configurations of dual bus modular (N+X) have more advantages. In the construction of information network power supplying system of industrial users, people always wrongly estimate the capacity of high-end UPS with higher or lower anticipation which results in high purchasing cost, failure to meet load demand or waste of resources, spaces and energy.

The dual bus modular (N+X) can effectively solve this problem through the extensible module structure, which can help users to construct and invest in stages under uncertain circumstances for the future. When the demand of using power loads of users is increasing we just need to add the power module in phases according to power use plan. Meanwhile, through the modular integration the expansibility requirement of system is able to be fully satisfied and also has the flexible mobility and better reliability which will be the milestone in the power supply protection fields.

In addition, as to traditional high-end UPS product, sing point fault tends to occur to single UPS. In the past, users choose traditional "1+1"or "N+1" redundant system which not only increases the cost of purchase, installation and maintenance but also only allow fault-tolerance for once.

In the dual bus modular (N+X) system, each single parallel module is the Intelligent individual of internal redundancy that doesn't need the system controller to have the centralized control for the parallel operation system. After any module (including the system control module) fails, the redundant design will maximally achieve the fault redundancy.

That means users just need to purchase the relative power modules to achieve the "N+X" fault redundancy upgrading capacity expansion in the dual bus modular (N+X) system which can effectively solve the UPS existed conditionality problem to let the users got the excellent expansibility. And also it can make the self-distribution and assembly for the system in the necessary time and decrease the initial purchasing costs for users.

According to the technological development level of current UPS industry, it is advisable to choose modular (N+X) UPS redundant power supplying system of "dual bus input" and "dual bus output" power supplying function

. It is composed of the following several power supply system:

1）Dual bus input power supplying system

The basic configurations of dual bus input power supplying are main power input supply + backup generators + "auto-switching" control cabinet + input power distribution cabinet. The auto-switching control system always monitors the real time operation status of all kinds of input power supply that can ensure to send the one route of most reliable supply to the input of UPS.

For some important IDC computer rooms, their "emergency generator" power supply is actually a set of multiple diesel generators and redundant power supply system consisted of generator set and cabinet.

2）Dual bus output power distribution system

To eliminate the "single point bottleneck" fault risk between the input of UPS parallel operation system and the user sides, it is necessary to configure with the dual bus output power distribution system. Its basic configurations consist of the "N＋1" type UPS redundant power supplying system (preferred, "1 +1" or "2 +1"-type parallel operation power supplying solution) + output distribution cabinet + load automatic transfer switch (LTS) .

As to some places with higher requirements, they should be configured with power supply system consisted of Load Bus Synchronization (LBS) and two sets of "N+1" modular (N+X) UPS redundant power supplying system with extremely high "fault-tolerance" function. In view of the fact that 30%-50% of servers and disk array machines and other product used in IDC computer rooms adopt "dual-supply power supplying" system, we can directly connect the separate supply from the two sets of "N＋1"parallel operation system with the two input ends of "dual-supply input device".

For the key loads which have the "single supply input power supplying" mode, we will separately connect the supply heads of two sets of "N＋1" type parallel operation system with the input ends of "automatic transfer switch(STS)" (commonly as STS type of static switch and SS type of fast switch) and then connect the key devices of users with the output ends of " automatic transfer switch(STS)".

·Reliability Analysis of Dual bus Modular (N＋ X):

Assessment the reliability of UPS to perform its duties not only consider the MTBF of UPS but also the MTTR of UPS and MTBF of main power. When UPS and main power fail at the same time, load will lost power supply which is the dereliction of key duty for UPS. The time that load expose without the protection of main power depends on the time of maintenance.

If maintaining one UPS needs one week so does mean time between failures (MTBF) of main power. When UPS fails, load is likely to lose power. If the MTTR of UPS is one hour the MTBF of main power would not greatly affect the failure probability of key loads. Apparently, reducing the MTTR of UPS will decrease the failure probability of key loads. The best way of reducing the MTTR of UPS is to reduce the factors which can affect the maintenance of UPS as much as possible. Because the dual bus modular (N+X) has the hot plug-in function it is the best choice for users.

From the perspective of design principle, the whole power supply system has to adopt redundant power supplying solution of high "fault-tolerance" function to ensure that whatever the main power electrical network or inverter of any modules (including the system control modules) fails and fuse burns out or the breaker trips the inverter of online type UPS will supply the power to the internet devices, it shouldn't be powered by main power or emergency backup generators through AC bypass. Because only inverter of online UPS is likely to provide the load of users with high-quality sine power with both stable voltage, non- frequency discontinuity, non-interference, minimum waveform distortion.

In summary, the dual bus modular (N+X) UPS has the longest mean time to failure (MTBF), minimum mean time to repair (MTTR), most powerful anti-interference ability and high "fault-tolerance" function. Applying this set of system will get stable, efficient, and safe and 24h discontinued power supply. It is model of latest professional power system for computer room and most reliable power supply.

·Choose UPS redundant power supplying system of better compatibility with IDC centralized monitoring system.

To meet the demand of information network to realize unattended management and remote centralized monitoring and control for IDC and MDC computer rooms and improve the "manageability" of UPS power supplying system, internet data center should build up a set of "non-IT devices" centralized monitoring system as well as configure with the real-time monitoring network management system for its IT devices. The purpose is to monitor and analyze the real-time situation of air-conditioner, power distribution cabinet, battery units, electric generating set, leakage alarm, security system, fire-fighting system and so on. So the selected UPS redundant power supplying system should configure with the following communication interfaces:

Run diagram:

Power supply schematic diagram: