Thermal Modeling and Experimental Validation in the Rotor Region of Hydrogenerator With Different Rotor Structures

Abstract

Thermal management is often considered a bottleneck in the pursuit of the next generation hydrogenerator in the electric power system. Overheating of the complex rotor parts has become one of the main problems affecting safe and stable hydrogenerator operation. In this paper, a 250 MW hydrogenerator is analyzed. The transient electromagnetic field of the hydrogenerator is calculated and the losses of the rotor parts are obtained. The rotation of the hydrogenerator rotor is considered. Three-dimensional fluid and thermal mathematic and physical models of the hydrogenerator are established. The loss values from electromagnetic field calculations are applied to the rotor parts as heat sources in the temperature field. After solving the fluid and thermal equations of fluid-solid conjugated heat transfer, influence of the structures of rotor support plate, rotor pole body insulation, and rotor excitation winding on the fluid flow and temperature distribution in the rotor region of hydrogenerator is studied using the finite volume method. The calculated temperature result of rotor excitation winding is compared with the measured value. The calculated temperature result agrees well with the measured value. It provides an important reference for optimizing the rotor structure of the larger hydrogenerator.

Loss Modeling of Large Hydrogenerators for Cost Estimation of Reactive Power Services and Identification of Optimal Operation

“…These more diverse operating regimes bring new economic costs into consideration, as the overall efficiency now becomes a significant differentiator [8]. Moreover, to deliver more reactive power, rotor cooling has been found to be a major limiting factor [12], which is known as the overheating problem in the thermal management [13], [14]. Accurate information about the stator's thermal footprint is also essential [15], and combined with the cooling arrangement, can establish a thermal network for the whole machine to predict the overall capability [16].…”

Loss Modeling of Large Hydrogenerators for Cost Estimation of Reactive Power Services and Identification of Optimal Operation

“…These more diverse operating regimes bring new economic costs into consideration, as the overall efficiency now becomes a significant differentiator [4]. Moreover, to deliver more reactive power, rotor cooling has been found to be a major limiting factor [8], which is known as the overheating problem in the thermal management [9], [10]. Accurate information about the stator's thermal footprint is also essential [11], and combined with the cooling arrangement, can establish a thermal network for the whole machine to predict the overall capability [12].…”

Influence of Eddy Current Loss on Electromagnetic Field and Temperature Field of High-Speed Permanent Magnet Generator With the Toroidal Windings

“…Since the HSPMG has high 30 power density, its loss density is also large [9], [10], [11]. 31 The generator overheating problem is serious that limits the 32 growth in power density while also affecting the reliability of 33 power supply [12], [13], [14]. As for the HSPMG, the eddy current loss occupies a higher percentage of the total loss, so the eddy current loss is a key issue in the investigation.…”