According to the physical structure and the mechanism of vocal cord voice and based on the hierarchical theory and acoustics theory, three masses model of vocal cord vibration is established. Using electricity power-sound analogy method, the equivalent diagram of the glottis is obtained and kinetic equations of vocal cords vibration are solved. Considering the possible changes of pathological vocal cord and selecting a series of vocal cord′s parameter values, the pathological vocal cords vibration is simulated. Our results show that the change of parameter in vocal cord's different layer structure will lead to different wave form of vibration and influence the vibration of other layer structure.

vocal colds; three mass blocks; model of vibration