Uninterruptible power supply is a system equipment that connects batteries (mostly lead-acid maintenance-free batteries) with the host, and converts DC power into city power through module circuits such as host inverters.
There are large and mini UPS. Large ups are used in mining, aerospace, industry, communications, national defense, hospitals, computer business terminals, network servers, network equipment, data storage equipment, emergency lighting systems, railways, shipping, transportation, power plants, substations, nuclear power plants, fire safety alarms system.
Wireless communication systems, program-controlled switches, mobile communications, solar energy storage energy conversion equipment, control equipment and it’s emergency protection systems, personal computers and other fields.
How UPS power supply works:
1. Bypass operation mode
When the online UPS is overloaded, the bypass command (manual or automatic), the inverter is overheated or the machine is faulty, the UPS generally converts the inverter output to the bypass output, that is, directly powered by the mains. Since the phase of the output frequency of the UPS needs to be the same as the phase of the mains frequency during bypass, the phase-locked synchronization technology is adopted to ensure that the UPS output is synchronized with the mains.
The bypass switch bidirectional thyristor works in parallel, which solves the problem of bypass switching time, truly achieves uninterrupted switching, and the control circuit is complex. It is generally used in medium and high Power UPS.
2. How the battery works
Once the mains is abnormal, the DC power stored in the battery is converted into AC power. At this time, the input of the inverter is supplied by the battery pack, and the inverter continues to provide power for the load to continue to use, so as to achieve the function of uninterrupted power supply.
The power source of the uninterruptible power system is the battery, and the capacity of the battery is limited, so the uninterruptible power system will not supply unlimited power like the mains. There must be a limited time to supply power.
Mini ups are used in WiFi routers, CCTV cameras, door controls, emergency lighting, vending machines, finger printers and other smart electric products.