UPS power supply is a relatively common emergency power system. Its working mode is different when the mains power is normal and abnormal. The following describes the four working modes of UPS power: normal operation, battery operation, bypass operation and bypass Road maintenance.
1. Normal operation mode
The power supply principle of the UPS power system is that when the mains power is normal, the machine will convert the AC power of the mains power into direct current, and then charge the battery for use when the power is interrupted; it should be emphasized that the uninterruptible power system is not only when the power is cut. When working, if the voltage is too low or too high, instantaneous surges, etc., which are enough to affect the power quality of the normal operation of the equipment, the UPS system is in working condition to provide stable and clean power to the load equipment.
2. Bypass operation mode
When the online UPS encounters power overload, bypass command (manual or automatic), inverter overheating or machine failure, the UPS power supply generally converts the inverter output to the bypass output, that is, it is directly supplied by the mains..Since the phase of the UPS output frequency must be the same as the phase of the mains frequency when bypassing, the phase lock synchronization technology is adopted to ensure that the UPS power output is synchronized with the mains.The bypass switch bidirectional thyristor works in parallel, which solves the problem of bypass switching time, truly achieves zero-time switching, and the control circuit is complicated. It is generally used in medium and high power UPS power supplies..If the UPS is overloaded, the load must be reduced artificially, otherwise the bypass short-circuiter will automatically cut off the output.
3. How the battery works
Once the mains power is abnormal, the DC power stored in the battery is converted to AC power. At this time, the input of the inverter is supplied by the battery pack. The inverter continues to provide power, and the load continues to be used to achieve the continuous power supply function..The power source of the UPS power system is the battery, and the capacity of the battery is limited. Therefore, the UPS system will not continuously supply power like the city electricity. The power supply time must be limited, if you want to extend the discharge time, you must purchase a long delay UPS power supply.
4. Bypass maintenance mode
When the UPS power supply is overhauled, the bypass is manually set to ensure the normal power supply of the load equipment. When the maintenance operation is completed, restart the UPS power supply, and the UPS power supply will turn to normal operation at this time.