Method for treating blockage of water loop of generator rotor

Abstract

The invention discloses a generator rotor water loop blocking treatment method. Dynamic alternating-current impedance and RSO tests are carried out at different rotating speeds (500, 165, 2260 and 300 revolutions) in the shutdown processing process, test results show that no obvious turn-to-turn short circuit exists in a rotor winding, and it is judged that hot bending of the rotor may be caused by blockage of a rotor waterway. The method comprises the following steps: checking a thermal bending treatment part of the generator rotor; performing a hydrostatic test on the rotor to analyze factors possibly influencing insulation; comprehensively cleaning bakelite gaskets at the joints of the positive and negative lead wires and the slip ring; the rubber sealing gasket on the large shaft side of the 17-way branch water joint is machined again, and the requirement for good pressure resistance, abrasion resistance and insulativity is met; the unit is started to run, the alternating current impedance and RSO tests of the rotor at different rotating speeds are qualified, the grid connection of the generator is successful, and the 5-watt and 6-watt vibrations are both within the qualified range. The method is used for generator rotor water loop blocking treatment.

Description

Technical Field

[0001] This invention relates to a method for treating blockages in the water circuit of a generator rotor. Background Technology

[0002] During generator operation, excessive vibration was observed in the 5th and 6th bearing shafts and other bearings. To rule out mechanical causes, adjustments to the excitation current revealed that the vibration of the 5th and 6th bearings was correlated with and trended in the same direction as the excitation current changes, but with a time lag. The excessive vibration was attributed to rotor thermal bending. During shutdown, dynamic AC impedance and RSO tests were conducted at different speeds (500, 1650, 2600, and 3000 rpm). The test results showed no obvious inter-turn short circuits in the rotor windings, suggesting that rotor thermal bending was likely caused by blockage in the rotor water circuit. Summary of the Invention

[0003] The purpose of this invention is to provide a method for treating blockage in the water circuit of a generator rotor, so as to solve the above-mentioned technical problems.

[0004] The above objectives are achieved through the following technical solutions: A method for treating blockage in the water circuit of a generator rotor, the method comprising the following steps: Step 1: Inspect the parts of the generator rotor that have undergone thermal bending treatment; Step 2: Conduct a hydrostatic test on the rotor to analyze factors that may affect the insulation; Step 3: Thoroughly clean the bakelite gaskets at the connection points between the positive and negative leads and the slip ring; Step 4: Re-process the rubber sealing gasket on the large shaft side of the 17-way branch water connector, requiring it to have good pressure resistance, wear resistance, and insulation; Step 5: The unit is started and run. The AC impedance and RSO tests at different rotor speeds are qualified. The generator is successfully connected to the grid. The vibration of 5 and 6 watts is within the qualified range.

[0005] The method for treating blockage in the water circuit of a generator rotor, wherein step one is as follows: (1) Check whether the connection between the inlet and outlet water pipes at the center of the rotor is blocked; (2) Check whether the fixing screws of the flange at the end of the water inlet pipe at the center of the rotor are intact. If there is rust, replace them. (3) Check whether the positioning pin at the rear of the rotor center return water pipe is effective. If it is not effective, remeasure the dimensions and replace it. (4) Before the water pressure test of the rotor water circuit, the water in the coil should be drained as much as possible, and then the air in the rotor water circuit should be evacuated to ensure the accuracy of the water pressure test data. (5) The negative electrode water flow rate weighing and the water flow rate comparison test of each branch can not verify whether the water circuit is unobstructed, because the water pressure cannot be guaranteed to be stable during weighing, and the data obtained is inaccurate. (6) When performing backwashing of the rotor water circuit, it is necessary to rinse not only the coil side, but also the shaft side.

[0006] The method for treating blockage in the water circuit of a generator rotor, wherein step two is as follows: (1) When the water pressure test of the 17 branch water connectors was completed and water was drained, some water flowed into the slip ring lead outlet. The moisture in that place could not be discharged due to the obstruction of the slip ring fan, resulting in low insulation.

[0007] (2) The 7-way branch water connector may have a high resistance grounding, resulting in low insulation. Therefore, it was decided to remove the slip ring fan and the 17-way branch water connector for separate verification. Beneficial effects

[0008] 1. This invention enables timely detection and elimination of potential equipment hazards, ensuring equipment and personal safety, and maximizing power generation while ensuring stable and reliable heating, thus achieving significant social benefits.

[0009] 2. This invention completely cleans the bakelite gaskets at the connection between the positive and negative leads and the slip ring. 2. The rubber sealing gaskets on the large shaft side of the 17-way branch water connectors are reprocessed to have good pressure resistance, wear resistance, and insulation. The AC impedance and RSO tests at different rotor speeds are qualified, the generator is successfully connected to the grid, and the vibration of the 5 and 6 watts is within the qualified range and has been significantly improved compared with before the repair. Thus, the treatment of generator rotor thermal bending and water leakage problems causing generator inter-turn short circuits is completely completed. Detailed Implementation

[0010] A method for treating blockage in the water circuit of a generator rotor, the method comprising the following steps: Step 1: Inspect the parts of the generator rotor that have undergone thermal bending treatment; Step 2: Conduct a hydrostatic test on the rotor to analyze factors that may affect the insulation; Step 3: Thoroughly clean the bakelite gaskets at the connection points between the positive and negative leads and the slip ring; Step 4: Re-process the rubber sealing gasket on the large shaft side of the 17-way branch water connector, requiring it to have good pressure resistance, wear resistance, and insulation; Step 5: The unit is started and run. The AC impedance and RSO tests at different rotor speeds are qualified. The generator is successfully connected to the grid. The vibration of 5 and 6 watts is within the qualified range.

[0011] The specific process of step one is as follows: (1) Check whether the connection between the inlet and outlet water pipes at the center of the rotor is blocked; (2) Check whether the fixing screws of the flange at the end of the water inlet pipe at the center of the rotor are intact. If there is rust, replace them. (3) Check whether the positioning pin at the rear of the rotor center return water pipe is effective. If it is not effective, remeasure the dimensions and replace it. (4) Before the water pressure test of the rotor water circuit, the water in the coil should be drained as much as possible, and then the air in the rotor water circuit should be evacuated to ensure the accuracy of the water pressure test data. (5) The negative electrode water flow rate weighing and the water flow rate comparison test of each branch can not verify whether the water circuit is unobstructed, because the water pressure cannot be guaranteed to be stable during weighing, and the data obtained is inaccurate. (6) When performing backwashing of the rotor water circuit, it is necessary to rinse not only the coil side, but also the shaft side.

[0012] The specific process of step two is as follows: (1) When the water pressure test of the 17 branch water connectors was completed and water was drained, some water flowed into the slip ring lead outlet. The moisture in that place could not be discharged due to the obstruction of the slip ring fan, resulting in low insulation.

[0013] (2) The 7-way branch water connector may have a high resistance grounding, resulting in low insulation. Therefore, it was decided to remove the slip ring fan and the 17-way branch water connector for separate verification.

Claims

1. A method for treating blockage in the water circuit of a generator rotor, characterized by: The method includes the following steps: Step 1: Inspect the parts of the generator rotor that have undergone thermal bending treatment; Step 2: Conduct a hydrostatic test on the rotor to analyze factors that may affect the insulation; Step 3: Thoroughly clean the bakelite gaskets at the connection points between the positive and negative leads and the slip ring; Step 4: Re-process the rubber sealing gasket on the large shaft side of the 17-way branch water connector, requiring it to have good pressure resistance, wear resistance, and insulation; Step 5: The unit is started and run. The AC impedance and RSO tests at different rotor speeds are qualified. The generator is successfully connected to the grid. The vibration of 5 and 6 watts is within the qualified range.

2. The method for treating blockage in the generator rotor water circuit according to claim 1, characterized in that: The specific process of step one is as follows: (1) Check whether the connection between the inlet and outlet water pipes at the center of the rotor is blocked; (2) Check whether the fixing screws of the flange at the end of the water inlet pipe at the center of the rotor are intact. If there is rust, replace them. (3) Check whether the positioning pin at the rear of the rotor center return water pipe is effective. If it is not effective, remeasure the dimensions and replace it. (4) Before the water pressure test of the rotor water circuit, the water in the coil should be drained as much as possible, and then the air in the rotor water circuit should be evacuated to ensure the accuracy of the water pressure test data. (5) The negative electrode water flow rate weighing and the water flow rate comparison test of each branch can not verify whether the water circuit is unobstructed, because the water pressure cannot be guaranteed to be stable during weighing, and the data obtained is inaccurate. (6) When performing backwashing of the rotor water circuit, it is necessary to rinse not only the coil side, but also the shaft side.

3. The method for treating blockage in the water circuit of a generator rotor according to claim 2, characterized in that: The specific process of step two is as follows: (1) When the water pressure test of the 17 branch water connectors was completed and water was drained, some water flowed into the slip ring lead outlet. The moisture at that point could not be discharged due to the obstruction of the slip ring fan, resulting in low insulation. (2) The 7-way branch water connector may have a high resistance grounding, resulting in low insulation. Therefore, it was decided to remove the slip ring fan and the 17-way branch water connector for separate verification.