Technical clarification on generator operation safety

l. For generators powered by internal combustion engines, the internal combustion engine part should be operated strictly in accordance with the safety of internal combustion engine operation.

2. For generators newly installed, overhauled or out of service for more than 10 days, the insulation resistance and absorption ratio of the stator and excitation circuit should be measured before use. The insulation resistance of the stator shall not be less than 30% of the last measured value, and the insulation resistance of the excitation circuit It should not be less than 05MΩ, the absorption ratio should not be less than l3, and the measurement record should be made.

3. Check the drive parts of the internal combustion engine and the generator before operation. The connection should be reliable, the wires of the output circuit should be well insulated, and the instruments should be complete and effective.

4. Before starting, the resistance value of the excitation rheostat should be placed at the maximum position, then the main switch of the power supply output should be cut off, and the neutral point grounding switch should be connected. For units with clutches, start the internal combustion engine at no-load operation first, and then connect the generator after it is normal.

5. After starting, check that the generator should have no abnormal noise during speed-up, the slip ring and the brushes on the commutator are in good contact, and there is no jumping or sparking. After the operation is stable and the frequency and voltage reach the rated value, power can be supplied externally. The load should be gradually increased, and the three corresponding guarantee periods should be balanced.

6. After the generator starts to run, it should be considered that all electrical equipment is live.

7. If the generator voltage is too low, it will have an adverse effect on the operation of the load (such as electric equipment), and it will also affect the operation of the engine itself. It will also affect the stability of grid-connected operation; if the voltage is too high, it will affect the safety of electrical equipment. In addition to operation, it will also affect the service life of the generator. Therefore, the maximum and minimum allowable voltage values ​​for continuous operation of the generator shall not exceed ±10% of the rated value. The voltage fluctuation range of its normal operation shall be within ±5% of the rated value, and adjustments should be made when the specified value is exceeded. When matching the rated value, the rated capacity of the generator should remain unchanged.

8. When the generator set is running at a high frequency, it is easy to damage the components and even cause an accident. When the generator is running at a too low frequency, it will not only have an adverse effect on the safety and efficiency of electrical equipment, but also reduce the speed of the generator. The temperature of the stator and rotor coils increases. Therefore, when the generator is running at the rated frequency, its variation range shall not exceed ±O5Hz.

9. The power factor of the generator shall not exceed the late phase (lag) 095. If there is an automatic excitation regulator, it can run under the condition of a power factor of 1. If necessary, it can be allowed to run in the late phase 095~l for a short time.

10. During the operation of the generator, check and confirm that the instructions of the various instruments and the operating parts are normal, and the load of the generator should be adjusted at any time. The stator and rotor current must not exceed the allowable value.

11. Before stopping, cut off the main switch of each power supply branch to gradually reduce the load, then cut off the generator power supply main switch, return the excitation rheostat to the maximum resistance position, and reduce the voltage to the lowest value, then cut off the excitation switch and the middle The grounding switch of the sex point, and finally stop the operation of the internal combustion engine.