相位偏差对米勒循环发动机性能的影响及其控制

李加旺，朱博铖，尹子明，王永生

奇瑞汽车股份有限公司，安徽 芜湖  241009

摘要：为精确控制米勒循环发动机相位偏差，分析相位偏差对米勒循环发动机功率、转矩和比油耗的影响，提出米勒循环相位偏差的控制目标，分析发动机相位偏差的来源，提出相位偏差控制方案。试验结果表明：米勒循环发动机对相位偏差更加敏感，相位偏差需要控制在曲轴转角±1°范围内。采用相位测量设备测量米勒循环发动机实际相位，根据实际相位和电子控制单元的预设相位对比，进行偏差补偿，实现精准控制。大量在线测量结果表明，测量凸轮升程位移精度为0.001 mm，相当于相位偏差在曲轴转角1°以内，满足米勒循环发动机相位偏差要求。

关键词：米勒循环；相位偏差；进气门早关；进气门晚关

Influence and control of phase deviation on Miller cycle engine

LI Jiawang, ZHU Bocheng, YIN Ziming, WANG Yongsheng

Chery Automobile Co., Ltd., Wuhu 241009, China

Abstract：In order to control the phase deviation of the Miller cycle engine precisely, the influence of phase deviation on power, torque and specific fuel consumption of Miller cycle engine is analyzed. Miller cycle phase deviation is chosen as control target, and the source of engine phase deviation is analyzed. The test results show that the Miller cycle engine is more sensitive to the phase deviation, which needs to be controlled within the crankshaft angle range of the ± 1°. The phase measurement equipment is used to measure the actual phase of the Miller cycle engine, and the deviation compensation is compared according to the preset phase of the electronic control unit (ECU) to achieve accurate control. According to the testing results, the solution measures the cam lift displacement accuracy of 0.001 mm, which is equivalent to the phase deviation within 1° crankshaft angle, meeting the phase deviation requirements of the Miller cycle engine.

Keywords:Miller cycle; phase deviation; early intake valve closing;late intake valve closing