Analysis of the cause of auxiliary generator failure

By analyzing the situation of such faults in HXN5 locomotives, combined with the principle of auxiliary generator starting control circuit, it is inferred that the reasons why the auxiliary generator does not generate electricity after the major reset may be the following.
1. The basic conditions for starting the auxiliary generator are not met
When the locomotive has faults such as control system disconnection, traction, resistance braking, and self-load invalidity, a major reset is required at this time, and the major reset requires the locomotive to stop and the diesel engine to stop and disconnect the corresponding circuit breaker. If the fault occurs in the section at this time, the train dispatcher urges the locomotive crew to drive as soon as possible, and the locomotive crew is not skilled in operation, etc., resulting in the auxiliary generator starting conditions not being met (such as the diesel engine speed is not maintained at 400-1050r/min for more than 20s, etc.), and the auxiliary generator motor vehicle is forcibly started. In the end, the auxiliary generator does not generate electricity, resulting in a machine failure, and rescue has to be requested.
2. Air compressor contactor contact adhesion
The three-phase power of the air compressor motor of the HXN5 locomotive is provided by the auxiliary generator. The air compressor motor has two working modes: low speed and high speed according to the air supply system and the working status of the diesel engine. The speed regulation of low speed and high speed is realized by controlling the sequential attraction of the three contactors on the air compressor motor. In actual work, because the contactor can generate a large current when it is attracted and disconnected, it is easy to cause the contactor contacts to stick, resulting in the auxiliary generator being protected and not generating electricity.
3. The auxiliary generator starting load is too large
From the starting process of the auxiliary generator, it can be seen that when the locomotive fails and the driver resets the auxiliary generator, when the auxiliary generator starts, as the voltage/frequency on the power supply coil increases, the AC generator fan motor and exhaust fan motor directly connected to the auxiliary generator power supply winding are put into operation first, but the auxiliary generator has not yet completed the start-up. The simultaneous input of the two motors will cause the auxiliary generator starting load to be too large, and ultimately cause the auxiliary generator to fail to start.