AC power supply system

The AC power supply system of the communication power inverter is composed of high-voltage power distribution equipment, step-down transformer, oil generator, UPS and low-voltage power distribution equipment. The AC power supply system can have three types of AC power sources: the mains power supplied by the substation, the self-contained AC power supplied by the oil generator, and the backup AC power supplied by the UPS.

(1) Oil-generators In order to prevent battery over-discharge caused by long power outages, telecommunications bureaus are generally equipped with oil-generators. When the mains power is interrupted, the communication equipment can be powered by the diesel generator set. The oil machine is divided into ordinary oil machine and automatic start oil machine. When the utility power is interrupted, the oil generator will automatically start to generate electricity. Since the mains power supply is more economical and reliable than that of the oil generator, the communication equipment is generally powered by the mains under the condition of the mains.

(2) In order to ensure that the communication power supply is uninterrupted and transient-free, UPS can use a static AC uninterruptible power supply system, also known as UPS. UPS is generally composed of batteries, rectifiers, inverters and static switches. When the mains is normal, the mains and the inverter are connected in parallel to provide AC power for the communication equipment, and the inverter is rectified by the mains to supply power to it. At the same time, the rectifier also charges the battery, and the battery is in a state of floating charge in parallel. When the commercial power is interrupted, the storage battery provides AC power to the communication equipment through the inverter, and the conversion between the inverter and the commercial power is completed by the AC static switch.

(3) AC power distribution panel The purpose of the AC power distribution panel is to input mains power and distribute power for various AC loads. When the mains is interrupted or the AC voltage is abnormal (overvoltage, undervoltage and lack of balance), the low-voltage power distribution panel can automatically send out corresponding alarm signals.

(4) Connection mode - AC power backup mode The AC power of large communication stations is generally supplied by the high-voltage power grid, and the independent power transformation equipment is prepared by itself. The base station equipment often rents civilian electricity directly. In order to improve the reliability of power supply, two substations are generally introduced into two high-voltage power sources by two substations in important communication hub offices, and they are introduced by dedicated lines, usually one for main use and one for backup, and then step down to supply various communication equipment and lighting through transformer equipment Equipment, in addition to have their own oil generator, in case of accidents. The general station only imports one line of mains power from the grid, and then connects to the self-provided oil generator as a backup. Some small office stations and mobile base stations only connect to the mains power supply (at the same time equipped with a battery with sufficient capacity), and the oil generator is a vehicle-mounted device.