摘要
以车速和发动机油门为控制参数,设计双离合器式自动变速器(Dual clutch transmission,DCT)的两参数换挡规律,硬件在环仿真结果表明该控制规律在城市工况极易导致频繁换挡,在制动工况容易产生意外升挡。分析不合理换挡现象的原因,并指出驾驶员的不合理操作习惯是引起频繁换挡和意外升挡的主要原因,两参数换挡规律不易避免不合理换挡现象。基于"sugeno"型模糊控制方法,建立智能修正型换挡规律的控制系统,该系统以油门开度和油门开度变化率为输入,实时升、降挡车速的修正系数为输出,确定隶属度函数并制定相应的模糊控制规则。智能换挡系统中的降挡速度为两参数降挡曲线临界值与降挡修正系数的乘积,升挡速度为两参数升挡曲线临界值与升挡修正系数的商。控制结果表明智能换挡规律在保留两参数换挡规律优点的同时,可以避免频繁换挡及意外升挡现象的发生,提高整车的舒适性和燃油经济性。
The double parameter shifting schedule （DPSS） of dual clutch automatic transmission （DCT） controled by vehicle speed and engine throttle opening, based on enine torque model, engine fuel model and gear ratios of DCT, is designed. In the hardware-in-loop simulation test, some unreasonable shifting phenoenmons such as frequent shifting in EUDC drive cycle and needless shifting in urgent braking condition are found. The reason of the unreasonable shifting phenoemnon is analyzed, then, the conclusion that the unreasonable shifting is mainly caused by the incorrect operation of the driver is presented, and the unreasonable shifting is hard to be avoided if the DPSS is used. To eliminate the improper shifting under certain driving conditions, an intelligent compensating shift schedule （ICSS） is devised on the basis of＂sugeno＂ fuzzy logic. The ICSS is composed of the input parameters including throttle opening and its changing rate, output parameters including upshift and downshift compensating ratio, membership function and fuzzy control principle. The downshifting speed at a given throttle opening is obtained from multiplying the corresponding speed inferned from DPSS by the downshift compensating ration inferred from ICSS, but the upshifting speed is obtained from dividing the corresponding speed inferred from DPSS by the upshift compensating ratio inferred from ICSS. The final test results prove the ICSS can eliminate the improper shifting in drive cycle and braking condition, and the fuel economy is also improved.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2009年第1期205-210,共6页
Journal of Mechanical Engineering
基金
上海市科委重大攻关(06dz11002)
国家高技术研究发展计划(863计划，2006AA11A102)
中国博士后科学基金(20080440380)资助项目。
关键词
双离合器式自动变速器
智能换挡规律
设计与应用
Dual clutch transmission Intelligent shifting schedule Design and application
