Solution to frequency instability fault of diesel generator set after starting:
1. After starting the diesel engine, increase the speed and observe whether the voltage and frequency are stable. With the increase of speed, the voltage and frequency fluctuation range is larger, but the diesel engine has tended to be stable and the exhaust is light gray. This indicates that the diesel engine is working normally, and the fault may be in the control box and exciter.
2. Using a multimeter to measure the exciter and related circuits, all abnormalities were found
3. The stability of the AVR control board was adjusted, but the fault was not resolved
4. After shutdown, use a 6V battery to magnetize the exciter, and then start the diesel engine until the speed reaches around 750r/min. The generator begins to build voltage, and the fluctuation range of voltage and frequency meets the technical requirements of the generator set.
5. After shutting down, restart the diesel engine and observe how the frequency and voltage of the generator react. It was found that the frequency and voltage were unstable again
6. After shutdown, increase the starting speed of the diesel engine (increase the fuel supply of the governor), restart the diesel engine until the speed reaches around 800r/min, at which point the frequency and voltage of the generator stabilize. But when the joystick was lowered to start the diesel engine, it was found that the frequency and voltage of the generator were unstable. After repeating several times, it can be concluded that the starting speed of the diesel engine of this diesel generator set must be between 750-800r/min for the generator to generate electricity, and the voltage and frequency fluctuation range meet the requirements.
The above Huaquan Power has provided a brief introduction, hoping to provide users with reference.
