Introduction to EPS working principle
EPS emergency power supply adopts single inverter technology, which integrates charger, battery, inverter and controller. The battery detection and shunt detection loops are designed inside the system. The working principle block diagram of other main components is like 1 WYS, WYS/B series intelligent emergency power supply, which adopts backup operation mode.
(1) When the mains power is normal, the mains supplies power to important loads through the mutual input device, and at the same time performs mains detection and battery charging management, and then the battery pack provides DC energy to the inverter. Here, the charger is a low-power DC power supply that only needs to provide the battery pack with a charging current equivalent to 10% of the battery pack capacity (Ah). It does not have the ability to directly provide DC power to the inverter. At this time, the city power supplies power to the users' various emergency loads through the power supply system composed of the EPS's AC bypass and transfer switches. At the same time, under the control of the EPS logic control board, the inverter stops working and is in an automatic shutdown state. Under this condition, the power source actually used by the user load is the city power from the grid. Therefore, the EPS emergency power supply is usually said to be working all the time in the sleep state, which can effectively achieve the effect of energy saving.
(2) When the mains power supply is interrupted or the mains voltage exceeds the limit (±15% or ±20% of the rated input voltage), the mutual input device will immediately switch to the inverter for power supply. With support, at this time, the power used by the user load is the AC power converted by the EPS inverter, not from the mains.