1． Inspection method
If the voltage increase of the generator does not reach the rated value, the inspection should be carried out according to the following procedures:
(1) Check whether generator stator voltmeter is normal
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(2) Check whether the excitation voltage and excitation ammeter indication are normal
(3) Check whether the generator excitation switch and excitation knife switch are properly closed and can be re-closed
(4) Check whether the generator excitation power supply generator is normal
(5) Check whether the primary fuse device of the generator is normal and whether the contact of the secondary automatic switch PT is good
(6) Check whether the DC power to the regulator is normal and whether the regulator is damaged
(7) Check whether the generator brushes are badly worn
(8) Check whether the electrical cabinet is abnormal
(9) If the above is normal, you should check whether the main motor is working well
2. Points to pay attention to during boosting operation
The boosting operation of the gasoline generator should be carried out after the speed of the generator has stabilized, and the following points should be taken into account into account:
(1) The increase should be done slowly, let the stator voltage increase slowly
(2) During the process of increasing the voltage, the voltage of the rotor, the stator current and voltage should be monitored and the stator voltage should increase uniformly. The stator current
must be zero. If current is detected, it means that there is a short circuit fault in the stator circuit. The excitation must be immediately cut off for inspection
to eliminate. the short circuit point
< p> (3) When the voltage reaches 50% of the rated value, theThree-phase stator voltage must be measured separately to see if it is balanced. Whenthe voltage reaches the rated value, check whether the zero sequence voltage of the generator is normal. When it is normal, it should be 3‰≤SV
(Assume zero is reached. -Sequence voltage is UO)< /p>
(4) During the process voltage increase, check the operating status of the generator and exciter, check whether the brush operation is normal
and whether the temperature of the inlet air and output, noise and vibration are normal. In the event of an accident, the generator and exciter may operate overloaded for a short period of permitted time and current. regulations in the event of accidental overload. When the generator is overloaded due to an accident, the generator input and output should be closely monitored. The temperature of the wind, the stato coilr and rotor, the outlet water temperature of the stator coil and rotor and the operating conditions of the brushes should be monitored. does not exceed the maximum value.
When the generator stator current exceeds the allowable value, the electrical personnel on duty should first check the power factor and voltage of the generator, and pay attention to the calculation of the multiple and duration current exceeding the admissible value. rated value, reducing the rotor current and reducing the stator current reaches the maximum allowed value.
But the power factor should not be too high and the voltage too low. If reducing the rotor current cannot reduce the stator current to the allowable value, the distributor should be contacted to reduce the active load of the generator.
Detailed information:
A small overload of power lines is pendingant a short period of time is usually allowed because the load current changes periodically and does not damage the line. If the motor starting current is large, it can reach about 7In, and the starting time is generally 4-15s. 7 In is to some extent a short circuit current, but it is a normal overload, so. the motor protection circuit breaker must be correctly selected.
Long-term overloading of power lines is not allowed, because the charging current is continuous and long-term, which will heat the insulating materials, conductive joints and terminals of the electric circuit and will cause damage. Serious overload The load may directly become a short circuit in a short time and cause a fire. Circuits such as lighting outlets are connected to too many devices.
Continuous overload operation for several hours is an abnormal overload.t the overload protection device must act effectively. Generally, the damage caused by overload current is not as direct as that of short circuit current, but over time it will collapse like an anthill, so precautions should be taken.
Baidu Encyclopedia - Generator
Baidu Encyclopedia - Overload Protection