After the generator speed is rated, when performing the voltage boosting operation, attention should be paid to the following:
(1) The voltage boosting should be performed slowly so that the stator voltage rises slowly.
(2) During the voltage boosting process, the rotor voltage, current and stator voltmeter indications should be monitored for a uniform rise. The stator current should be zero. If current is found, it means there is a short circuit point in the stator circuit, and the excitation should be cut off immediately for inspection.
(3) When the voltage rises to 50% of the rated value, the generator zero sequence voltage 3U0≤5V should also be checked.
(4) During the voltage boosting process, the working conditions of the generator and exciter should be checked, whether the brushes are running normally, whether the inlet and outlet air temperatures are normal, etc.
(5) After the voltage is increased to the rated voltage, the insulation condition of the rotor circuit should be checked. The positive and negative pole-to-ground voltages should be equal, and the sum of the two pole-to-ground voltages should be less than 80% of the inter-pole voltage.
The inspection items of the generator set are as follows:
1) The coil temperature and iron core temperature of the generator cannot exceed the standard.
2) The air temperature at the inlet and outlet of the generator cannot exceed the standard. Exceeding the standard
3) No spark in the carbon brush slip ring
4) No discharge or spark inside the generator
5) The excitation current and voltage of the generator should Corresponds to the primary voltage and current of the generator and cannot exceed the standard.