UPS compares the advantages of battery + inverter
In the early telecommunications room, 220V AC power was rectified to charge the 48V battery pack, and the battery pack directly supplied power to the program-controlled switchboard. With the application of computer networks and communication networks in telecommunication equipment rooms, it is necessary to provide high-quality 220V AC power. Due to the existing 48V battery pack, the battery pack+inverter method is usually used to convert 48V DC into 220V AC power supply for network power supply. There are many disadvantages to this method.
1. the essential purpose of UPS (Uninterruptible Power Supply System) is an uninterrupted power supply. When the city power grid meets the input range, it will supply power to the load through AC/DC and DC/AC dual conversion. When the city power grid exceeds the limit, the battery will power the bag. , When the UPS fails or is overloaded, the bypass power supply supplies power to the load. The UPS can be maintained online through the manual maintenance bypass switch during maintenance. With the battery pack + inverter power supply mode, when the battery pack fails and needs to be replaced, the system must be interrupted, which will cause considerable losses to the system. The uninterrupted use of UPS cannot be replaced by a battery pack + inverter.
2. The purpose of UPS is to realize the uninterrupted mutual switching of dual power sources, supply one-time backup time, voltage stabilization, frequency stabilization, isolation interference, etc. It can block the grid interference such as instantaneous discontinuity, harmonic interference, voltage fluctuation, frequency fluctuation, and surge before the load. Since the input DC bus and external battery pack of the UPS's inverter have no direct electrical connection with the user's original 48V communication power supply, there will be no conduction interference to the program control machine. In addition, to prevent external radiation interference, UPS usually adopts a steel plate frame structure, which eliminates radiation interference to other equipment while maintaining a beautiful appearance. RFI filters are used at its input and output ends to supply the load with purified AC power.
Regarding the 48V battery pack + inverter, the inverter power supply and the DC power supply used in the program-controlled computer room are the same battery pack. The inverter adopts a high-frequency pulse width modulation working method, and the back-irrigation noise interference will inevitably be serially connected to the input terminal of the program-controlled telephone, which will significantly affect the quality of the call.
3. Because the inverter is a fixed 48V power supply and the battery voltage is low when the output power requirement is more significant, the production process requirements of the power module are higher, so high-power inverters are challenging to realize. Currently, the largest inverter is about 15KVA. The DC voltage of the battery pack of the UPS itself can be as high as several hundred volts, so the power of a single unit can be immense.
4. Due to the small consumption of the 48V inverter power supply and the small scale of the manufacturer, its strength is brutal compared with UPS manufacturers. As a complete and independent power system, UPS has been produced worldwide for decades. The production scale is enormous, the technology is mature, and the reliability is high. In theory, its reliability index can reach hundreds of thousands of hours. The 48V inverter power supply is technically challenging to match.
5. To meet the needs of the rapid development of modern communication networks, UPS or inverters must have vital network management functions. LEUMSUPS provides users with 2 RS232 interfaces, one computer dry contact interface and 1 set of remote alarm relay contacts. Its complete network management software can adapt to different operating systems, can monitor 16 UPSs at the same time, and can watch more than 170 kinds of parameters. Its unique Life2000 remote monitoring software can keep your UPS under the supervision of professional engineers every day, ensuring you peace of mind. As for the 48V inverter, few manufacturers can provide such vital software functions due to the limitation of its production scale and scope of use.
6. Someone once pointed out that the disadvantage of UPS is that when the input voltage is too high or low, it turns to battery discharge. However, my country's power grid condition is usually poor, which will cause frequent battery discharge and shorten battery life. There is no need to consider this issue when using a 48V inverter. The powerful UPS manufacturers in the world today, such as LEUMS, have fully considered this problem in their design. LEUMSUPS, using advanced DSP control technology, has an ultra-wide input voltage range and can still output at full load within +25%, which significantly reduces the number of battery discharges. Its advanced intelligent battery management function makes its charger have tiny AC ripple, automatic temperature compensation of charging voltage, automatic payment of discharge end voltage with discharge time, automatic battery detection, battery life calculation and other functions, which extensively protect the battery, Which can extend battery life by 30%.
In summary, we believe that 48V inverters cannot reach the level of online UPS in terms of control technology, anti-interference, network management, power level, reliability, etc. Therefore, the online UPS should be the best choice in the telecommunications room.
Edit by Paco
