Dynamic Analysis of Dual Motor-Gear Electromechanical Coupling System

Aiming at the complexity of the dynamics analysis of the dual permanent magnet synchronous motor (PMSM)-gear structure used in some ship’s power propulsion systems, this research has modeled the vector control system of the PMSM and established the lumped parametric model of the 21-degree-of-freedom gear transmission system respectively; After comprehensively analyzing the coupling relationship between the PMSM control system and the gear transmission system, this research has proposed the electromechanical coupling model of the two, and the model has been simulated and solved under different speed conditions of the PMSM. After comparative analysis, the errors between the time-domain parameters of the simulated vibration acceleration signals and the experimental results are within a reasonable range; In the frequency-domain parameters, the errors between the gear meshing frequency (and its octave frequency) and the experimental results and theoretical calculations are within the permissible range, which verifies the reliability of the electromechanical coupling model. In the power spectral density diagrams of the current and acceleration signals, the modulation frequency generated by the mutual coupling of the current frequency and the gear meshing frequency can be observed, which is also a specific embodiment of the “electromechanical coupling” phenomenon.