The precise estimation of friction torque is essential for torque-based control in internal combustion en-gines. However,friction torque could vary significantly due to such factors as the wear and aging of the engine and the deterioration of oil viscosity. Fixed MAP of friction torque is beyond the requirement of precise estimation of fric-tion torque in ECU during its full lifetime. To address this issue,an on-line friction torque correction algorithm was designed after a control-orient model of friction torque was built. Two typical operation conditions,the engine stop process and injection shut-down process at high speed,were selected to estimate and correct friction torque on line. The results obtained by off-line calculation and on-line test in ECU demonstrated that the on-line adapted algorithm could improve the estimation accuracy of friction torque and showed an availability in estimating and correcting fric-tion torque of diesel engine on line.%发动机摩擦扭矩的精确估计对基于扭矩的发动机控制策略有重要意义。机械磨损、老化、机油黏度恶化等因素会使发动机摩擦扭矩发生变化。固定的摩擦扭矩 MAP 无法满足 ECU 全生命周期对摩擦扭矩精确估算的要求。为解决此问题，建立了面向控制的摩擦扭矩模型，在此基础上设计了发动机运行过程的摩擦扭矩修正算法，选择停机及高速断油工况用于摩擦扭矩的在线估计和修正。离线计算及 ECU 在线测试结果表明，摩擦扭矩在线修正算法能够有效提高发动机摩擦扭矩的准确性，可用于在线估计与修正柴油机摩擦扭矩。
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