Auxiliary generator starting process

When the control system detects that all three conditions are met, the control system starts the auxiliary generator program. The auxiliary generator startup process mainly includes the battery excitation stage, the power storage and auxiliary generator excitation control (AAC) stage, and the AAC excitation control stage.
1. Battery excitation stage
The locomotive control system causes the excitation relay contact FFR to be energized, and the current in the battery begins to excite the auxiliary generator. At this time, the output windings of the auxiliary generator begin to output voltage.
2. Power storage and AAC excitation stage
The output end of the auxiliary generator is directly connected to the AC generator, ventilator, motor, and exhaust fan motor for ventilation and filtration of the auxiliary cabinet. The auxiliary generator control system detects the voltage/frequency (V/Hz) on the power supply coil to adjust the excitation. When the auxiliary generator control system detects that the output voltage/frequency of the auxiliary generator power supply coil is about 0.38, the auxiliary generator control system triggers the built-in SCR rectifier bridge to rectify, and together with the battery, excites the auxiliary generator, and the output voltage/frequency of the auxiliary generator power supply coil is also increasing.
3. AAC excitation and regulation
As the output voltage/frequency of the auxiliary generator power supply coil increases, the auxiliary generator excitation current also increases, and the corresponding auxiliary generator power supply coil output voltage/frequency also increases. When the auxiliary generator control system detects that the auxiliary generator power supply coil output voltage/frequency is about 3.0, the FFR is disconnected, and the battery no longer excites the auxiliary generator, but only the auxiliary generator is excited by the rectifier bridge SCR built into the auxiliary generator control system. The auxiliary generator control system controls the current size after the rectifier bridge SCR rectification to control the size of the voltage/frequency output of the auxiliary generator power supply coil. When this value reaches 3.83, the auxiliary generator is able to provide the required power for other auxiliary systems on the locomotive. At this time, the auxiliary generator is started. This process of the auxiliary generator program takes about 2s.