Configuration and Selection of Batteries in UPS Power Supply System

In UPS power supply system, it can be said that battery is the pillar of this system. UPS without batteries can only be called voltage stabilized and frequency stabilized power supply. The reason why UPS can achieve uninterrupted power supply is due to the existence of batteries. When planning UPS, first of all, we should consider which type of battery to choose, that is, the extra voltage of the battery, the extra capacity and the number of battery combinations to be applied.
(1) Selection of extra capacity of storage battery
Because the actual usable capacity of the battery is closely related to such factors as discharge current, system voltage, discharge time, operating environment temperature, storage time, load type and characteristics. The capacity of the battery generally refers to the power output (W) of the battery when the discharge rate reaches 1.75V/cell at 20 C for 20 hours.
(2) Selection of Battery Indicators
Internal resistance: Batteries with small internal resistance should be selected so as to sustain high current discharge. If the internal resistance is large, the power consumption increases during charging and discharging, which makes the battery hot.
Floating charge voltage: At the same temperature, high floating charge voltage means large storage energy, and low floating charge voltage of poor quality batteries is generally smaller. The floating charge voltage of storage battery should be corrected at different temperatures.
In large and medium-sized UPS (several kVA-several thousand kVA), 2V single-system batteries are selected to avoid the use of small-capacity combined batteries for hybrid connection