Views: 0 Author: Site Editor Publish Time: 2023-08-18 Origin: Site
It is a kind of energy storage device, with rectifier and inverter as the main components, which provides constant voltage and constant frequency uninterruptible power supply for the load in the substation.
The UPS system in the substation is generally composed of three parts: the main engine, the bypass voltage stabilizing cabinet, and the output feeder cabinet (small power can also be three-in-one), as the picture shows
- Convert alternating current (AC) into direct current (DC), which is filtered and supplied to the inverter
-Provide charging voltage to the battery and act as a charger
Convert direct current (DC) to alternating current (AC) for load use
UPS is used as a device for storing electrical energy, so that when the mains power fails, it can invert the DC power and provide uninterrupted power for the load. Its capacity determines its maintenance discharge (power supply) time
Also known as a static switch, it is an AC switch composed of two thyristors (SCR) connected in reverse parallel, and its closing and opening are controlled by a logic controller.
In the input or output part, the AC and DC are isolated, and the voltage stabilizer has the function of stabilizing the voltage in addition to isolation
With automatic voltage regulation, power failure protection and other functions, the conversion time is about 10ms
With filtering function, strong ability to resist mains interference, conversion time is less than 4ms
The structure is relatively complex, the performance is perfect, and it can solve power problems such as spikes, surges, and frequency drift
As the AC power supply of important equipment, it can prevent the sudden power failure of the mains from affecting the work and causing harm to the equipment
Eliminate "power pollution" such as power surges in the mains, instantaneous high/low voltage, wire noise and frequency deviation, improve power quality, and provide high-quality power for computers, etc.
Normal operation mode
Under normal AC power supply, the rectifier converts AC to DC, eliminates "power pollution" in the mains, and simultaneously charges the battery. It is then supplied to the inverter to convert the DC power into AC power to provide a more stable power supply to the load. as the picture shows
When the AC power supply is abnormal or the rectifier or reactor fails, the battery pack will provide DC power to the inverter, so that the AC output will not be interrupted, thereby achieving the function of protecting the load. as the picture shows
Backup power mode
When the inverter has abnormal conditions such as inverter fuse blown, short circuit and other faults, the inverter will automatically cut off to prevent damage. If the bypass AC power supply is normal at this time, the static switch will transfer the power supply to the bypass backup The power output is used by the load. as the picture shows
Maintenance bypass mode
When the UPS needs to be repaired or replaced and the load power supply cannot be interrupted, the inverter switch can be cut off first, then the maintenance bypass switch can be activated, and then the rectifier and bypass switch can be cut off. The AC power supply continues to supply AC power to the load through the maintenance bypass switch. At this time, maintenance personnel can safely maintain the UPS. as the picture shows