Model predictive controller-based multi-model control system for longitudinal stability of distributed drive electric vehicle

Ke Shi; Xiaofang Yuan; Liang Liu

doi:10.1016/j.isatra.2017.10.013

Model predictive controller-based multi-model control system for longitudinal stability of distributed drive electric vehicle

ISA Trans. 2018 Jan:72:44-55. doi: 10.1016/j.isatra.2017.10.013. Epub 2017 Nov 10.

Authors

Ke Shi¹, Xiaofang Yuan², Liang Liu¹

Affiliations

¹ College of Electrical and Information Engineering, Hunan University, Changsha 410082, China.
² College of Electrical and Information Engineering, Hunan University, Changsha 410082, China. Electronic address: yuanxiaofang@hnu.edu.cn.

PMID: 29132741
DOI: 10.1016/j.isatra.2017.10.013

Abstract

Distributed drive electric vehicle(DDEV) has been widely researched recently, its longitudinal stability is a very important research topic. Conventional wheel slip ratio control strategies are usually designed for one special operating mode and the optimal performance cannot be obtained as DDEV works under various operating modes. In this paper, a novel model predictive controller-based multi-model control system (MPC-MMCS) is proposed to solve the longitudinal stability problem of DDEV. Firstly, the operation state of DDEV is summarized as three kinds of typical operating modes. A submodel set is established to accurately represent the state value of the corresponding operating mode. Secondly, the matching degree between the state of actual DDEV and each submodel is analyzed. The matching degree is expressed as the weight coefficient and calculated by a modified recursive Bayes theorem. Thirdly, a nonlinear MPC is designed to achieve the optimal wheel slip ratio for each submodel. The optimal design of MPC is realized by parallel chaos optimization algorithm(PCOA)with computational accuracy and efficiency. Finally, the control output of MPC-MMCS is computed by the weighted output of each MPC to achieve smooth switching between operating modes. The proposed MPC-MMCS is evaluated on eight degrees of freedom(8DOF)DDEV model simulation platform and simulation results of different condition show the benefits of the proposed control system.

Keywords: Distributed drive electric vehicle (DDEV); Model predictive controller (MPC); Multi-model control (MMC); Recursive Bayes theorem; Slip ratio control (SRC).