Structural Design and Thermal Management Efficiency Study of a High-Stability Doubly-Excited Synchronous Generator

In response to challenges arising from the large-scale integration of new energy sources into power systems, issues such as frequency and voltage stability, peak shaving capability, transient stability, and dynamic stability of the power grid have garnered considerable attention. The research on key equipment, namely the doubly-excited synchronous generator (DESG), characterized by robust stability and the capability for deep-phase operation, has become a focal point. However, addressing the diverse operational requirements under various conditions, the design of rotor topology and thermal balance of the DESG remain unresolved. This study presents a theoretical derivation of the mathematical model for the synchronous axis system of the DESG. Building upon this, an investigation into rotor topology design is conducted, considering factors such as rotor slot pitch, rotor excitation winding arrangements (symmetric and asymmetric, single-layer and double-layer, orthogonal and non-orthogonal), and air gap length. Additionally, a finite volume method is employed to explore the thermal balance issues and optimize the cooling structure of the DESG under stringent operating conditions. The research outcomes contribute theoretical foundations and technical support for the development of high-power doubly-excited synchronous generators by large-scale power generation equipment manufacturers.