Abstract：The excitation system is important to the operation of synchronous generator. Third harmonic excitation system (THES) has the characteristics of self-excitation and excellent dynamic characteristics, and is widely used in small and medium-sized synchronous motors. In order to establish the model of the THES, firstly, the third harmonic electromotive force (EMF) formula is deduced, according to the struct of the harmonic windings. Then, based on the common synchronous motor model, the influence of harmonic winding on its rotor motion equation is introduced. Finally, the control block diagram of the closed-loop excitation system is analyzed. Based on Matlab/Simulink, the model is verified. The simulation results show that the transient voltage recovery of the synchronous generator with harmonic excitation is fast and the overshoot is small. Therefore, the model provides a basis for further research.
2020, Vol. 21 
