Nonlinear Disturbance Observer of Clutch Slipping Torque for Multi-Mode Hybrid Electric Vehicles

Abstract

Clutch slipping torque varies complicatedly and has a strong nonlinearity during the mode transition of hybrid electric vehicles. In order to estimate the clutch slipping torque, an online estimator based on the nonlinear disturbance observer (NDO) is proposed. First, an estimation-oriented model of the clutch slipping torque is established based on the LuGre friction model. Next, the NDO is designed to estimate the unknown part of clutch slipping torque based on the dynamics of the output shaft, while the output shaft torque required by NDO is estimated by a Luenberger state observer. To verify the effectiveness of the proposed estimator, experiments are conducted under different initial slipping speeds and inlet oil temperatures. The results show that the proposed estimator gains high accuracy.

摘要

在混合动力车辆的模式切换过程中, 离合器滑摩扭矩呈现复杂变化以及强非线性。本文提出基于非线性扰动观测器(Nonlinear Disturbance Observer, NDO)的实时估计方法实现对于离合器滑摩扭矩的估计。首先, 基于LuGre摩擦模型建立面向估计的离合器滑摩扭矩模型。其次, 根据输出轴动力学响应设计NDO实现对于离合器滑摩扭矩未知部分的估计。同时, NDO需要的输出轴扭矩通过Luenberger状态观测器进行估计。为了验证估计方法的有效性, 进行不同初始滑摩转速以及入口油温的台架实验。结果表明提出的估计方法有较好的估计精度。