Introduction: The Power Dispatch Center requires that the AC Uninterruptible Power Supply (UPS) system be responsible for supplying power to the system equipment and some of the backup lighting equipment in the transfer center and information center. Taking into account the characteristics of the power supply load, the power load capacity and the reliability, etc., the UPS parallel redundancy method should be selected to ensure the power supply to the various process equipment of the building.
The two mains I and the mains II supplied by the distribution transformer of the building are switched by the incoming line power cut screen, and the two AC power sources are output. The AC power is input to the UPS through the barrier transformer and the UPS power input screen. On the one hand, the input blocking transformer can improve the power quality of the input UPS power supply and reduce the harmonics. On the other hand, when the surge, induced overvoltage, etc. occur, the UPS power supply and future power equipment can play a certain degree. Protection effect.
After communicating with customers, we provide plans that are compatible with customer requirements. The two UPSs are operated in parallel with a 300KVA 12-pulse blocking transformer, and are powered by two mains. If the mains power is lost, the linkage switch in the power inlet screen is self-closing, and the two UPSs are powered by the mains.
In order to facilitate the maintenance and protection in the future, a large bypass is set up, which can bypass the entire UPS system and use the mains II as the bypass power supply.
The UPS power supply unit screen is placed in the UPS power supply room on the 21st floor of the building. Three-phase four-wire copper busbars are connected between the power screen and the screen to minimize unnecessary switches. The screen cabinet and the in-screen equipment have strong functions and high stability.
The method of using UPS power to share the battery pack, that is, when a UPS power supply is faulty or overhauled, it can switch its battery to another UPS power supply to extend the discharge time, in order to prevent the damage caused by the battery life. In a power distribution system, the two-sided UPS output total power distribution screen placed in the UPS power supply room and the distribution electric screens placed in the machine rooms in the 19th to 24th floor power dispatching centers of the building are included. From the UPS output total power distribution panel to the distribution screens of all professional computer rooms, redundant double-circuit line power supply is used. Circuit breakers are installed at both ends of each line. One line or fault or maintenance during the process does not affect the other. The power supply to the return line does not affect the normal operation of the secondary equipment.
The single-phase switch in the sub-distribution screen selects the bipolar air switch according to the requirements of the tender, so that the A, B, C phase switches are evenly arranged, and the load of each phase is balanced.
The battery occupies a very important position in the management of the UPS system. The monitoring and control methods will affect the life of the battery and the reliability of the UPS itself.
Each UPS is equipped with a battery for 1 hour. The power supply system provided by the seller shall have intelligent management of the battery, use micro-processing control, have active "charge-discharge" protection function, and strictly follow the battery charge/discharge curve operation. In the case of not blocking the mains, not affecting the operation of the inverter, and not using the battery capacity at all, the battery condition is discriminated, and the abnormal situation is alerted to prevent human damage and illegal operation. Through power management software, you can also actively shut down the device and save important data in critical situations.
In order to use the capacity of the battery to a greater extent, the two sets of batteries of the two UPS power supplies connected in parallel can be switched to be connected to one UPS for parallel operation when one UPS is out of operation. It is required to supply one battery power distribution panel with a battery manual linkage switch to ensure the above safe switching operation.