Deping Fu

Study on 3D temperature distribution in new evaporative cooling asynchronous generator

Evaporative cooling, is superior to other cooling methods. It offers a safe, reliable, and effective whole surrounding for insulation and heat transfer of the running stator. So its temperature distribution is worthy of being profoundly researched. According to the acceptant technics condition of the manufacture, the paper offers a kind of new stator insulation structure adapting to evaporative cooling mode. It is based on a commutate asynchronism generator of high power density and speed. By calculation and testing, this paper studies the heat distribution of the new insulation system formed by gaseity liquid, and solid. And by comparing between calculation and testing results, a feasible research to the new insulation structure has been given. While the rated load of the new insulation structure stator is decided. The papers valuable research conclusion may be regarded as an academic foundation for the same generators

Research on two-phase flow instability in two parallel hollow conductors in the evaporating cooling generator

As a new generator cooling technology, the evaporative cooling technology has been researched on various aspects to a certain extent, such as the two-phase flow pressure drop, temperature distribution and etc. But there has no research reported on the two-phase flow instability in the parallel hollow conductors in the evaporative cooling system. The occurrence of two-phase flow instability phenomena can probably make some system parameters change abnormally, such as flux and temperature, and make the cooling system operate abnormally. So its necessary to pay more attention to the instability of two-phase flow to assure the generators cooling effects. In this paper, the two-phase flow instability in two parallel hollow conductors was researched through theoretical simulation and experiments and the boundaries of the instability starting were obtained. The conclusion provides the reference basis for the actual operation of the evaporative cooling system in a certain sense.

Developing of turbo generator based on evaporative cooling technique and analysis to key factors

Cooling technique is one of the most important parts to improve the development of turbo generator. From the earliest air cooling technique to the modern water and hydrogen cooling technique, turbo generator is optimized constantly. Evaporative cooling technique is the latest one utilized to cool turbo generator, and we believe that it ought to bring a great progress in improving the efficiency, reliability, security and economics of turbo generator. In this paper, we describe the applications of evaporative cooling technique to cool the electrically active components of generator and analysis to the key factors. The advanced cooling systems are outlined according to the capability of turbo generator, which will provide references for generator designers.

Research on heat transfer of spraying evaporative cooling technique for large electrical machine

A heat transfer calculation approach of spraying evaporative cooling is presented according to its characters using in large electrical machine. Based on the parameters of coolant, fluid and surface structure the calculation approach is confirmed, and gain the relationship between convective heat transfer coefficient and heat flux. Experiment model of spraying evaporative cooling electrical machine is built, and perform the heating and cooling experiment. The temperature distribution of experiment model is calculated by FEM taking the theoretical result of convective heat transfer coefficient as the boundary. The results of calculation and experiment are consistent, which shows that the boundary of calculation is suitable, and this method can be used in the calculation and design of spraying evaporative cooling electrical machine.

300MW level evaporative cooling turbine generator stator temperature field analysis

Evaporative cooling technology is an innovative technology developed in China, it is the first time the technology been used on the development of the 300MW level turbine generator, the technology features simplified structure and uniform distribution of temperature. In this article, based on the analysis of the heat radiation of the high capacity generator, we calculate the 3D temperature field of the hottest section of the turbine generator stator under steady state with the 3D finite element method, and provide the related radiation parameters for calculation of temperature rising with the radial heat hydrotubation process been taken into account. The calculated results was been compared with the measured values. Besides, we also provide the calculation and analysis under the overloaded situation of the generator operation, which will provide theoretical base for the development of high capacity evaporative cooling turbine generator.