Dynamic Characteristics of Electrically Assisted Turbocharger Rotor System Under Strong Impacts

The electrically assisted turbocharger (EAT) integrates high-speed motors into the turbocharger rotor shaft to improve the turbocharger’s transient response performance. However, this integration introduces complexity to the turbocharger structure, impacting its dynamic characteristics. Moreover, due to the complex working environment of vehicles with varying road surfaces and strong longitudinal elevation changes, EAT is subjected to complex external impacts. This situation tests the stability of the rotor-bearing system.

A nonlinear dynamics model of the rotor bearing of an EAT supported by two floating ring bearings (FRBs) is developed using the lumped mass method and Capone’s model, and an impulse shock model is obtained using the time-domain representation method. The dynamic response of the system under strong impacts is obtained, with a particular focus on the variation in the FRB oil film thickness.

By analyzing the effects of different rotating speeds, pulse intensity, and radial clearance of FRBs, the operational reliability of FRBs under strong impact is revealed. Optimizing the structural parameters of FRB can improve the stability of the EAT under different strong impacts. These results provide valuable insights for the design and operating conditions of EATs.