CVT混合動力再生制動控制策略與仿真研究（本科畢業(yè)論文設(shè)計）

摘    要

混合動力汽車（HEV）是一種既具有傳統(tǒng)內(nèi)燃機汽車優(yōu)良的動力性又有純電動汽車低排放、高效率的新型汽車，是當(dāng)前最具有可行性的低排放、低油耗特點的新一代清潔汽車。
再生制動（能量回饋制動）對混合動力汽車的燃油經(jīng)濟(jì)性、排放性和行駛安全性都有直接影響，是混合動力汽車的重要工作模式，它能在車輛減速或制動過程中，在保證車輛制動性能的條件下，將車輛動能或位能通過帶動電機發(fā)電，轉(zhuǎn)化為電能儲存在電池中，實現(xiàn)能量回收，同時產(chǎn)生車輛所需全部或部分制動力。既實現(xiàn)了車輛的減速和制動，又有效地降低了整車的燃油消耗和污染物排放。
無級自動變速器（CVT）是具有自動連續(xù)改變速比的特性的新型變速器，當(dāng)車輛處于驅(qū)動工況時，調(diào)節(jié)速比使發(fā)動機按最佳燃油經(jīng)濟(jì)性曲線或最佳動力性曲線工作，可以顯著提高汽車的燃油經(jīng)濟(jì)性，改善汽車的動力性和乘坐舒適性，降低發(fā)動機的排放污染；當(dāng)車輛處于制動工況時，可利用CVT 速比的連續(xù)變化特性，使混合動力汽車上發(fā)電機的轉(zhuǎn)速獨立于車速的變化，通過調(diào)節(jié)CVT速比調(diào)節(jié)發(fā)電機轉(zhuǎn)速，使電機工作在高效區(qū)域，最大程度地回收能量。
本文以CVT 混合動力轎車為研究對象，對混合動力汽車再生制動系統(tǒng)進(jìn)行了理論分析與功能仿真，取得了如下成果：
1.通過對混合動力汽車的制動過程進(jìn)行動力學(xué)分析，參照傳統(tǒng)汽車的制動力分配方法，并接合CVT 無級變速的特點，提出了基于整車安全制動和高效能量回收的混合動力汽車制動力分配策略和控制方法。
2.根據(jù)本文研究的混合動力汽車，通過Matlab/Advisor軟件相關(guān)數(shù)據(jù)建立混合動力汽車再生制動系統(tǒng)的數(shù)學(xué)模型。
3.根據(jù)混合動力汽車再生制動系統(tǒng)的工作特點，提出了專門用于評價混合動力汽車能量回收效果的性能指標(biāo)－有效能量回收率。并選擇了典型城市驅(qū)動工況作為仿真工況。
4.通過對典型城市驅(qū)動循環(huán)工況的仿真和汽車制動能量回收率的分析，表明采用本文所提出的制動力分配控制策略在保證整車制動安全性的基礎(chǔ)上能高效回收整車的制動能量，有效能量回收率達(dá)到了24%。

關(guān)鍵詞：混合動力汽車，再生制動，控制策略，建模與仿真
 

ABSTRACT

Hybrid Electric Vehicle (HEV) is a new style vehicle, which combines the excellent performance of conventional vehicle with low emission and high efficiency of Electric Vehicle. HEV is the most feasible clean vehicle in the near future.
Regenerative braking (energy recovery braking) is one of key techniques for HEV,which has a direct impact on fuel economy, emission and vehicle security. During deceleration and braking, regenerative braking system will reverses its electric motor turning it into an electric generator for generating electricity from vehicle kinetic energy and potential energy, and supplying the whole braking forces or partial braking forces at the same time. Finally, electric energy is saved into the battery. Regenerative braking not only realizes the braking and deceleration, but also reduces fuel used and emission.
Continuously Variable Transmission (CVT) can automatically change the speed ratio continuously, which can make engine work on the optimal fuel economy operation line or the optimal driving performance line so it can rise the fuel economy and improve driving performance and comfort, reduce the emission of engine when the vehicle is in driving situation, or disconnect the rotate speed of engine and the velocity of vehicle when the vehicle is in braking situation which can make the motor work on the most efficient region by adjusting the ratio of CVT to adapt to the rotate speed of motor, thereby reclaims energy mostly.
Focus on CVT Hybrid Electric Vehicle.The deeply theoretical researching and system simulation are completed in this paper. The main results include:
1. Based on the dynamics analysis of the vehicle and braking force distribution of conventional vehicle and combined with the characteristic of CVT, a strategy for the braking force distribution and control of HEV which aim at assuring the vehicle security and high efficient energy recovery is proposed.
2. Through the Matlab/Advisor database, a regenerative braking system model is built.
3. A performance index is proposed for the energy recovery results based on the working feature of regenerative braking system on HEV. System simulations is completed in typical city drive cycles.
4. The simulation results in drive cycles show that regenerative braking force distribution control strategy can assure the braking security and high efficient energy recovery. The coefficient of recovery reach 24％.

     
Key words：Hybrid Electric Vehicle (HEV), Regenerative braking, Control strategy, Modeling and Simulatio
 

目   錄

中文摘要 Ⅰ
ABSTRACT Ⅱ
1緒論 1
  1.1 混合動力汽車概述 1
    1.1.1混合動力汽車的研究背景及意義 1
    1.1.2混合動力國內(nèi)外發(fā)展現(xiàn)狀 1
  1.2 混合動力汽車再生制動研究背景及現(xiàn)狀 3
    1.2.1 再生制動的研究背景 3
1.2.2 國內(nèi)外研究現(xiàn)狀 4
  1.3 本課題研究目的和主要內(nèi)容 5
    1.3.1 本課題的來源和研究目的 5
    1.3.2 本課題研究的主要內(nèi)容 5
 2 小型混合動力汽車再生制動控制策略研究 7
   2.1 汽車制動過程的動力學(xué)分析 7
     2.1.1 汽車行駛的動力學(xué)基礎(chǔ) 7
     2.1.2 汽車制動過程的動力學(xué)分析 9
 2.1.3 傳統(tǒng)汽車制動過程的制動力分配 10
 2.2 混合動力汽車再生制動控制策略 13
 2.2.1 混合動力汽車制動過程的制動力分配 13
 2.2.2 定比例制動力分配的能量回收控制策略 14
 2.2.3 基于電機高效發(fā)電的CVT速比控制策略 16
 2.2.4 混合動力汽車再生制動控制策略 18
 2.3 本章小結(jié) 19
 3 CVT混合動力汽車再生制動系統(tǒng)的理論建模 20
 3.1 混合動力汽車再生制動系統(tǒng)的建模基礎(chǔ) 20
 3.2 CVT混合動力汽車整車參數(shù)計算模塊的建模 20
 3.3 本章小結(jié) 23
 4 CVT混合動力汽車再生制動系統(tǒng)對能量回收的仿真與分析 24
 4.1 CVT混合動力汽車再生制動仿真工況選擇 24
 4.1.1 典型城市驅(qū)動工況的選擇 24
 4.1.2 CVT混合動力汽車再生制動系統(tǒng)仿真的評價指標(biāo) 25
 4.2 CVT混合動力汽車再生制動系統(tǒng)在典型城市工況下的仿真分析及參數(shù)優(yōu)化 25
 4.3 本章小結(jié) 29
5 結(jié)論 30
致謝 31
參考文獻(xiàn) 32