Stator winding operation temperature monitoring. In general, the temperature monitoring of stator winding is detected by thermometer. The manufacturer installs resistance thermometer in the slot and detects the temperature of the equipment through the thermometer. The monitoring process is to embed thermocouple with special wire rod and test the temperature through the heat conduction effect of thermocouple. Generally, the environment for temperature measurement is the thermoelectric temperature of winding under rated working condition The temperature at the highest temperature is 30 ℃ ~ 40 ℃ higher than that between bars in the slot.

定子绕组绝缘老化。定子绕组绝缘作用非常重要，其能够起到减缓机械老化、减缓电老化、减缓承受热老化的作用，此三者如果作用不好，则会让设备的老化速度加快，对设备的长期使用产生损害。对于机械老化，企业在解决此问题的时候大多在端部应用环氧适形材料，通过玻璃丝带加固，槽位进行毛毡垫条，双侧打紧槽楔，此方法能够解一时的燃眉之急，但是经过多年的运行之后，其稳定性依然受到挑战，尤其槽楔部分，松动明显，需重新固定。对于电老化，其为绝缘体外表面的防晕结构，此结构对于端部和槽部的完善情况还有待改善，绝缘内部的空气消除还没有达到理想目标。对于热老化，则主要考虑对其温度的检测，要注意温度不要超过绝缘体所承受的值。

Insulation aging of stator winding. The insulation function of stator winding is very important, which can slow down the mechanical aging, electrical aging and thermal aging. If these three functions are not good, the aging speed of the equipment will be accelerated and the long-term use of the equipment will be damaged. For mechanical aging, when enterprises solve this problem, most of them apply epoxy conformal materials at the end, which is reinforced by glass ribbon, and the slot wedge is tightened on both sides. This method can solve the urgent problem, but after years of operation, its stability is still challenged, especially the slot wedge, which is obviously loose and needs to be fixed again. For electrical aging, the emphasis is placed on the anti corona structure on the external surface of the insulation. The improvement of the structure for the end and groove needs to be improved, and the air elimination inside the insulation has not reached the ideal goal. For thermal aging, the main consideration is the detection of its temperature, which should not exceed the maximum value of the insulator.

定子绕组绝缘污秽。当前阶段，很多水轮发电机组内部都会出现积灰现象，常年使用所产生的油污也比较严重，积灰与油污的产生对于设备的运行影响较大，同时也会影响铁芯的散热情况，严重情况下还会引发火灾事故。通常在检修过程中，使用压缩空气吹扫，或者使用毛刷、白布与溶剂进行清洁，次清洁方式容易使设备清洁不到位，无法达到更本清洁的目的。

The insulation of stator winding is polluted. At the present stage, many hydro generating units will have ash accumulation inside, and the oil pollution caused by annual use is also relatively serious. The dust accumulation and oil pollution have a great impact on the operation of the equipment, and also affect the heat dissipation of the iron core, and even cause fire accidents in serious cases. Usually, in the process of maintenance, compressed air is used for purging, or brush, white cloth and solvent are used for cleaning. The secondary cleaning method is easy to make the equipment not clean in place and can not achieve the purpose of more clean.

4 发电机灭火装置。现阶段我国使用的灭火装置大多为水器灭火，灭火设备也多为人为操作进行灭火。灭火应当为在发电机组管控设备出现跳闸情况，管理人员发现设备出现冒烟情况或者闻到有焦糊味道的时候，立即进行灭火操作。首先使用手动关闭灭火装置的渗漏排水阀，之后打开供水阀，保证水源的充足供应，启动消防阀，同时要对发电机的孔盖和门进行关闭，给水延续到发电机下部盖板已经漏水为止。但是当前阶段对于供水阀、排水阀、消防阀的检修不到位，在使用过程中发现阀门无法使用，引起火势蔓延。

4 generator fire extinguishing device. At present, most of the fire-fighting devices used in our country are water extinguishers, and most of the fire-fighting equipment is manually operated. The fire fighting shall be carried out immediately when the control equipment of the generating set trips and the management personnel find that the equipment is smoking or smelling burnt smell. First, manually close the leakage drain valve of the fire extinguishing device, and then open the water supply valve to ensure the sufficient supply of water, and start the fire valve. At the same time, the hole cover and door of the generator should be closed, and the water supply should continue until the lower cover plate of the generator has leaked. However, at present, the maintenance of water supply valve, drain valve and fire valve is not in place, and it is found that the valve can not be used in the process of use, causing fire spread.