To solve problems of water cold turbo-generator under the blocking fault, the eddy-current losses of hollow and solid strands were calculated using numerical method, and the conjugate heat transfer model for stator fluid and temperature fields was established. The complex distribution of fluid velocities in the radial ventilation duct and hollow strands was obtained and the calculated temperature results were compared with the measured values, which verify the accuracy of the calculation results. The stator temperatures of the generator with hollow strand blocking were analyzed and the influences of blocking hollow strands numbers and locations on the main insulation were investigated. A new structure of stator windings was proposed, which can reduce the stator highest temperature effectively under the blocking fault. Using the new structure, the highest temperature can reduce 47 ℃ when the hollow strands are blocked. It provides theory basis for preventing insulation aging and damaging by the thermal stress. The structure optimization reduces the danger of insulation burnt down under strands blocking fault.%为分析水内冷发电机定子绕组堵塞故障下绕组的发热问题,采用数值方法计算空心和实心股线的涡流损耗,建立定子流体场与温度场共轭传热计算模型,得到发电机径向通风沟和空心绕组内流体复杂分布,将所得温度结果与实测值进行了对比,验证计算结果的准确性；分析发电机空心股线发生堵塞故障下定子线棒的温度分布,研究股线堵塞位置及堵塞根数对发电机绝缘性能的影响；提出一种有效降低堵塞故障下绕组最高温度的绕组新结构,绕组采用该结构能使发电机发生堵塞故障后最高温度降低47℃,为预防主绝缘老化及热应力对电机绝缘的损害提供理论依据,降低发电机股线堵塞故障下绝缘烧毁隐患的发生.
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