| The goal of this thesis is to research the topologies of Doubly Salient Generators (DSG). Series of new Doubly Salient Electromagnetic Generators (DSEG) with single-phase, two-phases and multiple-phases are developed based on the normal 6/4-pole structure, and their no-load characteristics and load characteristics are researched.In this thesis, the concept of element generator is proposed first. On the basis of the three-phase 6/4-pole element generator, series of 6/4N-pole element generators of DSEG with multiple rotor poles are deduced. Then, the value of N, the relation between N and the phase sequence, the ratio of pole arc width to polar distance of stator and the expression of electric potential waveform width are researched. Three conditions for the new generator structure are further obtained. The combinations between stator pole and rotor pole, the ratio of stator pole arc width to pole distance and the phase winding connections are further analyzed for the new element generators with single-phase, two or four-phase and five-phase DSEG. A new multiple poles hybrid excited element generators and multiple units multiple poles hybrid excited element generators are intruduced.The macros of the force and torque in the interesting areas are built, and the Finite Element Analysis (FEA) models, which calculate the flux, Electromotive Force (EMF), inductance, torque and force of DSEG, are realized and optimized by ANSYS. The field, air gap flux density, EMF, inductance, cogging torque and stator pole force of a 2kW, 500r/min prototype are analyzed. Partial results of the calculation are compared with the experiment data, and verified the finite element models above. The no-load characteristics of four phases and five phases DSEGs are researched, and the open circuit fault tolerances capabilities of five phases DSEG are obtained. According to the analysis of three phase 24/16-pole hybrid excitation DSG modal, the field regulation characteristics and no-load characteristic are invovled. The influence of air gap length on the slot leakage, the edge effect between stator pole and rotor pole of megawatt DSEG are investigated and the no-load characteristics of DSEG with different air gaps are compared. When the inner diameter of stator, the effective length of stator core, the air gap flux destiny and the rotation speed of the generator are fixed, the affect of pole number to phase voltage per turn of no-load characteristic is discussed.The FEA load models of DSEG are developed by ANSOFT. The load field, air gap flux density and phase current of a prototype are analyzed. Part of the calculation results are compared with the experimental data. The comparison results verify the FEA model well. The Switched Reluctance Generation mode (SRG mode), Doubly Salient Generation mode 1(DSG1 mode) and Doubly Salient Generation mode 2(DSG2 mode) of external characteristics and power curves are comparatively studied from the prototype. The influence of structure parameters on megawatt DSEG external characteristics and power characteristics is mainly researched, including turns-in-series each phase, core length, inner diameter of stator, exciting current and rotate speed. Different generation modes of SRG and DSG2 modes on external characteristics and power are further studied. The volumes, weights, losses and costs of six 2MW design examples effective material are estimated and compared.
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