Communication base station power supply operation mode
Operation mode of DC power supply system
The operation mode of the DC power supply system of the switching office adopts the -48V full floating charge power supply mode. That is, when the mains is normal, the AC mains is first rectified by the high-frequency switching power supply, and then float-charges the battery pack and supplies power to the communication equipment;
When the mains (failure) fails and the generator set does not start to supply power, the battery pack discharges to provide DC uninterrupted power supply to the communication equipment, and the allowable discharge time is generally 1 to 2 hours;
When the power supply of the generator set or the mains is restored, the DC power supply system is firstly charged by constant voltage and current limit, and then transferred to the floating charge mode for power supply.
The operation mode of the DC power supply system of the mobile base station (or optical cable, microwave relay station) generally adopts the -48V full floating charge power supply mode. That is, when the mains power is normal, the rectifier module on the combined switching power supply rack is connected in parallel with the battery for float charging and supplies power to the communication equipment;
When the mains (failure) fails and the mobile generating set fails to supply power, the battery pack is discharged in parallel to supply power to the communication equipment;
When the power supply of the generator set or the mains is restored, the DC power supply system is firstly charged by constant voltage and current limit, and then transferred to the floating charge mode for power supply.
The difference between the DC system of the mobile base station and the DC system of the switching office
When the battery of the base station is discharged to the set point of the first-level cut-off voltage (about 3 hours), the base station equipment with a heavy load is automatically disconnected to ensure the normal operation of the transmission equipment for a long time (about 20 hours);
If the mains power failure lasts for a long time and the mobile generating set is not on the station, the battery output will be automatically disconnected when the battery discharges to the cut-off voltage, so as to avoid battery damage caused by continuous discharge of the battery. Therefore, the mobile generating set should go to the station to generate power before the battery is discharged to the cut-off voltage, so as not to cause interruption of communication.
Equipment Configuration Principles of DC Power Supply System
The equipment configuration and wire selection of the DC power supply system are mainly based on the short-term and long-term DC load survey statistics of various communication equipment in the communication bureau (station), to configure the capacity and quantity of high-frequency switching rectifiers, battery packs, and AC-DC power distribution panels. Wire diameter and specification model.
The capacity of AC and DC power distribution panels is configured according to the long-term load, and its output load shunt can be determined according to the needs of electrical equipment.
The capacity of the high-frequency switching rectifier should meet the sum of the short-term communication load and the battery charging load at the same time. The number of rectifier modules should be configured in a redundant (N+1) manner.
The capacity of the battery should be able to meet the specified allowable discharge time requirements.
The wire diameter of the DC power supply busbar should be able to meet the maximum allowable voltage drop in the whole process of the DC power supply circuit.
