Principle of DC system - News

(1) Composition:

The DC system is mainly composed of AC power distribution, charging module (also called DC module), monitoring device (including: insulation monitoring device), battery pack, bus voltage regulation (step-down silicon chain), DC feed-out branch (including: DL combined brake circuit, GK closing circuit, control circuit, emergency lighting, etc.)

(2) Principle:

When the AC input of the system is normal, one of the two AC inputs is selected through AC automatic switching control, and supplies power to each charging module through AC power distribution. The charging module converts the input three-phase alternating current into a direct current of about 380V/240V, which is isolated by an isolation diode and then output. On the one hand, it supplies power to the DC load, and on the other hand, it charges two sets of batteries.

The monitoring device in the system manages and controls the system. After the signal is collected and processed, it is then managed uniformly by the monitoring module, which provides a man-machine operation interface on the LCD screen and can be connected to the remote monitoring system. The system is equipped with insulation monitoring, which is used to monitor the insulation condition of the busbar.

When the AC input fails or is abnormal, the charging module stops working and the battery supplies power to the load. The monitoring device monitors the battery voltage, current and discharge time, and when the battery is discharged to a certain extent, the monitoring module gives an alarm. After the AC input returns to normal, the monitoring module automatically selects the charging mode according to the battery discharge condition, and controls the charging module to charge the battery.