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The aim of the study was to investigate the difference between car-to-e-bikes and car-to-pedestrian accidents. The China In-depth Accident Study (CIDAS) database was searched from 2011 to 2013 for pedestrians and e-bikes struck by car, van and SUV fronts, which resulted in 104 pedestrian and 85 e-bike cases where information was sufficient for in-depth analysis. Reconstruction by PC-Crash was performed for all of the sampled cases. Pre-crash parameters were calculated by a MATLAB code. Focus was on prototypical accident scenarios and causes; speed as well as possible prevention countermeasures. It has been shown that traffic light violations, road priority violations, and unsure safety (these situations included misjudgments, unpreparedness, proximity to other road users, inappropriate speeds, etc.…) are the main causes in both the VRU groups. Distinctions were found for aspects of car collision speed, accident scenario, distribution of head contact points and so on.

The sideband current harmonics generated by the voltage source inverter (VSI) and its related space vector pulse-width modulation (SVPWM) method are the main causes of the high-frequency vibro-acoustics responses in permanent magnet synchronous motor (PMSM). In this study, a novel hybrid carrier frequency modulation (HCFM) method based on the modified zero-vector action time of dynamic space is proposed to supress current harmonic, and reduce sideband vibro-acoustics. Firstly, since the zero-vector action time of different space angles can directly affect the current harmonic amplitude, the six traditional spaces are dynamically re-divided into twelve subspaces. Then, the carrier frequency is actively adjusted, according to based on the action-time variation tendency of the dynamic zero-vector in different subspaces for suppressing the current harmonic amplitude. The correlation of the current harmonic power spectral density of the HCFM method is deduced.