Influence of Complex Fluid Flow on Temperature Distribution in the Rotor Region of Large Hydrogenerator Under the Rotor Rotation

Abstract

Ventilation cooling design is one of the key technologies during the design of large hydrogenerator. With the increase of hydrogenerator capacity, the overheating problem of rotor region become more and more serious. In this paper, a 250 MW hydrogenerator is analyzed. The transient electromagnetic field of the hydrogenerator is calculated. The losses (heat sources) of rotor components in the rotor region of the hydrogenerator are determined. Three-dimensional fluid and thermal coupled mathematic model of the hydrogenerator rotor region is established. The rotor rotation of the hydrogenerator is considered. The distribution of complex fluid velocity in the rotor region is calculated using the finite volume method. The influence of fluid velocity in the different directions on the temperature of the rotor excitation winding is studied under the different flow rates in the rotor region. The surface heat-transfer coefficient distribution of the rotor components is determined. The temperature distribution of the rotor excitation winding, rotor pole body, rotor press plate, rotor damping bar, and rotor end ring is obtained. The calculated temperature results match well with test values. These provide an important reference for the rotor structural design and optimization of larger hydrogenerator.INDEX TERMS Hydrogenerator; electromagnetic field; rotor rotation; fluid velocity; different directions; temperature distribution.

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.…”