The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Spray cooling is a new type of high heat flux heat transfer cooling technology. In the process, cooling medium is dispersed certain microscale droplets through the nozzles and injected to the stator core and winding. The spray characteristics will affect directly the heat transfer coefficient. So in the paper a test rig using a nozzle was constructed to explore the atomization characteristics of spray...
Overload performance of permanent magnet motor is very important for some special occasions, which has been generally limited by temperature rise of stator. This paper introduces a new method based on heat storage of phase change paraffin to enhance the overload performance of motor. The heat variation of motor was analyzed under overload process, and the key affecting factors were given to control...
With the increase of the electrical machines capacity and voltage level, the main insulation of the stator coil becomes thicker. Heat dissipation and voltage endurance becomes a contradiction. The traditional cooling, such as air-cooling and water-cooling, will not well meet design needs. New cooling methods with both advantages of good cooling effect and good insulation are in keen demand in industry...
With the increase of motor capacity and voltage grade, the thickness of the stator insulation certainly will be more and more thick. So these factors will make the design of the insulation and cooling critical. In this work, in order to apply spray evaporative cooling to the large motor, new insulate system is researched experimentally by IEECAS. And it adequately research on testing of partial discharge...
Spray cooling is a kind of phase change cooling technology. The heat transfer is more effective than traditional and immersing evaporative cooling, due to the combined effect of forced convection and nucleate boiling. In the process, cooling medium is sprayed into certain micro-scale droplets through the nozzles and injected to the stator core and winding. The spray characteristics will affect directly...
Based on engineering application, the researchers put forward to further optimization design to the spray evaporative-cooling electrical machine. In this paper, the optimization design is introduced in detail. The cooling structure and system parameters will also be provided. All these optimization designs will provide more design basis for evaporative cooling design.
In 2010, the spray evaporative cooling technology was applied successfully to large electrical machines by IEECAS. But the heat transfer mechanism of two-phase spray cooling has not been studied in detail. Based on the engineering application, in this paper, the heat transfer characteristics of the spray evaporative cooling system will be discussed. The conclusion will provide reference for the design...
To accurately segment putamen with fuzzy edges of basal ganglia region in brain Magnetic Resonance (MR) images, a shortest path based interactive segmentation method is proposed in this paper. Considering anatomical features of putamen, a cost function is designed by using weight coefficients in sub-regions and sub-orientations, and the shortest path search is restrained in a region, so that the fuzzy...
Radial ventilation channel is a key component of large turbo generator stator, which affects the cooling of stator core and bars. The design of radial ventilation channel need simultaneously consider the flow resistance and cooling capacity. In this paper, the width of radial ventilation channel, the structure and material of support parts will be discussed to improve the cooling capacity of large...
Inner evaporative cooling way of stator bars is generally affected by circulating system and coolant. In this paper, we focus those factors to improve the capability of cooling system. Based on the flowing resistance distribution of system, the structure of components is redesigned to improve the stability and reliability of circulating flow. In the same time, different kinds of coolant are used into...
The coolant temperature of the condenser outlet is a parameter reflecting the condenser's performance in the evaporative cooling system of the hydro-generators, which was usually assumed to be a reasonable value in the previous simulation. However, with the change of the work state of the generator, the coolant temperature of the condenser outlet will be corresponding change, it is necessary to correctly...
The coolant dryness of the hollow conductor outlet is an important parameter relevant to the working state of the evaporative cooling system. It was calculated by the balance equation of the flowing pressure and the flowing resistance in the past. The conventional method was complex, therefore a new calculation method on the basis of the condenser's heat balance equation and over-all heat transfer...
when we design immersing evaporative cooling turbo generator, How to control the temperature rise of stator bars in an appropriate situation is one of the most important parts in the unit designing. In this paper, the heat flowing paths of stator components are analyzed in the immerging stator structure. Based on the heat transfer theories, Numerical simulation model is built for the stator temperature...
At present, the GPS system is used more and more widely, and the research on the GPS signal is the basis in this field. Therefore, based on the basic principle and structure of the satellite signal, and aim at the pseudo-random code C/A-code, P-code's characteristics character which GPS signal adopt analysis and research the production method, then simulation the realization based on Matlab/Simulink...
In order to solve the cooling problem of the large electrical machine under special situation, the staff of IEECAS brought forward new coolant and cooling structure for spraying evaporative cooling system based on experiences of evaporative cooling electrical machine for many years. The article discusses detailed the key problems include systems structure, theory calculation and experiment. By the...
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...
Matrix rectifier is evolved from the traditional three phase to three phase matrix converter, and inherits merits of the traditional matrix converter, so it obtains more attention in recent years. According to transformer, matrix rectifier topology falls into the isolated and non-isolated topology. Now the existed modulation strategy mostly focuses on space vector modulation study and is realized...
In the paper, we discuss the integration of electrical machines with evaporative cooling technology. Introduce the integration methods and correlation experiment analyses, put forward a new kind of stator insulation structure for evaporative cooling generator with high power density. And the integration of the power devices and other connective equipments makes the total system became unitary. Thus...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.