关键词: 怠速抖动；燃烧稳定性；点火提前角；刚体模态

Abstract: This paper mainly studies the problem of seat jitter under idle conditions, identifies the time-frequency characteristics of regular jitter and irregular jitter, and analyzes the mechanism and main influencing factors of the two types of jitter. To solve the problem of irregular jitter, it is clear that the engine combustion stability has a greater influence on irregular jitter, and the engine combustion torque has a smaller influence on jitter. The experiment verifies the trend of idle jitter under different ignition advance angles and different carbon tank operating frequencies. Through the case of A vehicle irregular jitter problem, the control suggestions of engine combustion stability and combustion parameters are put forward. Aiming at the problem of idle speed rule jitter, the beat vibration of engine and transmission is determined to be the main incentive of rule jitter, and the mechanism of the beat vibration is analyzed. Based on the case of the rule jitter problem of a type B vehicle, the design suggestions of assembly rigid body mode and engine shaft frequency avoidance are put forward.

Key words: idle dithering; combustion stability; ignition advance angle; rigid body mode