The UPS is a common emergency power system. The UPS works in different modes when the mains is normal and when the mains is abnormal. The following describes the UPS working modes: normal operation, battery operation, bypass operation, and bypass maintenance. 1. Normal operation mode The power supply principle of the UPS power system is that when the mains is normal, the machine will convert the alternating current of the mains to direct current, and then charge the battery for use in case of power interruption. It should be emphasized that the uninterruptible power system does not work during power outage. For example, when the voltage is too low or too high, or the transient surge is enough to affect the power quality of the normal operation of the equipment, the UPS system is in the working state to provide stable and clean power for the load equipment. 2. Bypass operation When the online UPS encounters power overload, the bypass command (manual or automatic), the inverter overheats, or the machine is faulty, the UPS switches the inverter output to bypass output, that is, the mains supply power directly. In bypass mode, the UPS output frequency and phase must be the same as the mains frequency. Therefore, the phase-locked synchronization technology is used to ensure that the UPS output is synchronized with the mains. Bypass switch bidirectional thyristor parallel working mode, solve the problem of bypass switching time, truly achieve zero time switching, control circuit is complex, generally used in medium and high power UPS power supply. If the UPS is overloaded, manually reduce the load. Otherwise, the bypass short-circuiter automatically cuts off the output.
3, battery working mode once the mains abnormal, will be stored in the battery in the direct current into alternating current, at this time the input of the inverter by the battery pack to supply, the inverter continues to provide power, supply load continue to use, to achieve continuous power supply function. The power source of the UPS power system is the battery, and the capacity of the battery is limited, so the UPS system will not continue to supply power like the market, so no matter how much capacity of the uninterruptible power system, in its full load state, the power supply time must be limited, if you want to extend the discharge time, you must buy a long delay UPS power supply. 4. Bypass maintenance When the UPS power supply is being repaired, manually set the bypass to ensure normal power supply to the load device. When the maintenance is complete, restart the UPS power supply.
