1. Working Principle of Dual Clutch Automatic Transmission双离合自动变速器（简称DCT）基于手动变速箱基础之上。而与手动变速箱所不同的是，DCT中的两幅离合器与二根输入轴相连，换挡和离合操作都是通过一集成电子和液压元件的机械电子模块来实现。而不再通过离合器踏板操作。就像tiptronic液力自动变速器一样，驾驶员可以手动换挡或将变速杆处于全自动D挡（舒适型，在发动机低速运行时换挡）或S挡（任务型，在发动机高速运行时换挡）模式。此种模式下的换挡通常由挡位和离合执行器实现。两幅离合器各自与不同的输入轴相连。如果离合器1通过实心轴与挡位1、3、5相连，那么离合器2则通过空心轴与挡位2、4、6和倒挡相连。 双离合变速箱通俗的说就是，这种变速速箱形式就有两个离合器，一个控制1、3、5档，一个控制2、4、6档。使用一档的时候二档已经准备好了，同理，所以换档时间大大缩短，没有延时。

　　Double clutch automatic transmission (DCT) is based on manual transmission. Unlike manual gearbox, two clutches in DCT are connected with two input shafts. Shifting and clutch operation are realized by a mechanical and electronic module which integrates electronic and hydraulic components. And no longer through the clutch pedal operation. Just like tiptronic automatic transmission, drivers can shift gears manually or in full automatic D-shift (comfortable, shifting at low speed) or S-shift (task, shifting at high speed) mode. Shifting in this mode is usually achieved by gear and clutch actuators. The two clutches are respectively connected with different input axes. If clutch 1 is connected to gear 1, 3 and 5 through solid axis, then clutch 2 is connected to gear 2, 4, 6 and reverse through hollow axis. Dual clutch gearbox is commonly said that this form of gearbox has two clutches, one control 1, 3, 5 gear, one control 2, 4, 6 gear. When using the second gear, the second gear is ready, the same is true, so the shift time is greatly shortened and there is no delay.

　　2、市面上常见的几种双离合自动变速器形式：

　　2. Several common types of dual clutch automatic transmission on the market:

　　大众：DSG双离合器变速箱

　　Volkswagen: DSG Dual Clutch Gearbox
                    

　　很多国人对于双离合变速器的认识也是从DSG开始。当然，大众的“双离合”也是比较有代表性的，旗下大部分进口车也都配有DSG，如高尔夫GTI，EOS，迈腾和尚酷等。 大众EOS采用的就是DSG双离合变速箱不过，现今大众其实共有两款DSG双离合变速器，在大众内部代号分别为DQ250和DQ200，从直观数据上分析，代号DQ250的DSG有六个挡位，能承受较大扭矩为350NM，主要用于高排量或主打操控性的车型，如高尔夫GTI和即将上市的09款迈腾；而DQ200则是七速双离合变速器，能承受较大扭矩为250NM，主要搭载于中低排量的车型，如下半年上市的高尔夫6、速腾等。

　　Many Chinese people's understanding of double clutch transmission also begins with DSG. Of course, Volkswagen's "double clutch" is also representative. Most of its imported cars are equipped with DSG, such as Golf GTI, EOS, Mayton Monk Cool and so on. Volkswagen EOS uses DSG dual-clutch gearbox. However, there are actually two DSG dual-clutch gearboxes in Volkswagen nowadays. The internal codes are DQ250 and DQ200. From the visual data analysis, the DSG coded DQ250 has six gears and can withstand the maximum torque of 350NM. It is mainly used for high displacement or main control vehicles, such as Golf GTI and the upcoming 09 Maiteng. DQ200 is a seven-speed dual-clutch transmission, which can withstand a maximum torque of 250 NM. It is mainly equipped with low and medium displacement models, such as Golf 6 and Suoteng, which are listed in the following six months.

　　沃尔沃：POWERSHIFT双离合器变速箱

　　Volvo: POWERSHIFT Dual Clutch Gearbox

　　与大众所采用的干式离合器的DSG变速箱不同，Powershift所采用的是湿式双离合器，是将离合器片浸泡在机油当中，来对其进行冷却。离合器可以将动力输送给六个档位中的任何一个，由电脑控制的离合器根据汽车速度和转速对驾驶者的换档意图做出判断，可以预选择下一挡位从而实现档位的快速切换。 POWERSHIFT双离合器变速箱[3] 由于Powershift变速箱可以设定在电脑控制的“自动”模式之下，或者利用方向盘上的拨片来实现手动换档。搭载2.0升四缸涡轮柴油的C30、S40和V50是首批配备这种变速箱的车型。虽然这台发动机的较大功率和扭矩分别为136马力和320牛米，但这种双离合变速箱可承受的较大扭矩输出达到450牛米。

　　Unlike the DSG gearbox of the dry clutch used by the public, Powershift uses a wet dual clutch, which immerses the clutch slice in the oil to cool it. The clutch can transfer power to any of the six gears. The computer-controlled clutch can judge the driver's shift intention according to the speed and speed of the car, and can select the next gear in advance to realize the fast shift. POWERSHIFT Dual Clutch Gearbox [3] Because Powershift Gearbox can be set in the "automatic" mode controlled by computer, or manual shift can be achieved by using the dial on the steering wheel. C30, S4 0 and V50 with 2.0 liter four-cylinder turbo-diesel are the first models equipped with such gearboxes. Although the maximum power and torque of the engine are 136 horsepower and 320 km2 respectively, the maximum torque output that the dual clutch gearbox can withstand is 450 km2.

　　保时捷：PDK双离合器变速箱

　　Porsche: PDK Dual Clutch Gearbox

　　PDK双离合器变速箱其原名为保时捷Doppel Kupplungen，当然就是双离合器变速系统的德文，而PDK便是取名自德文原名中三个单字的前缀字母的组合。根据消息显示，这个全新的双离合器变速系统工作原理与VW集团的DSG相同，也同样具备附在方向盘后方的换档拨片，让驾驶者手不需离开方向盘就可以进行换档控制的功能。 保时捷——PDK双离合器变速箱PDK双离合器变速箱同样具备两组离合器，分别负责奇数与偶数档位，换档速度要比现在大多数普通的手排变速箱快很多，保时捷的大多数车款将把这个双离合器变速箱作为选购配备。

　　The original name of PDK dual clutch gearbox is Porsche Doppel Kupplungen. Of course, it is German for dual clutch transmission system. PDK is a combination of three prefix letters from the original German name. According to the news, the new dual clutch transmission system works on the same principle as the DSG of VW Group, and also has the shift pad attached to the rear of the steering wheel, so that the driver can shift without leaving the steering wheel. Porsche - PDK dual clutch gearbox PDK dual clutch gearbox also has two sets of clutches, responsible for odd and even gears, shift speed is much faster than most of the ordinary manual gearbox, most of Porsche's cars will use this dual clutch gearbox as an optional equipment.

　　Maintenance of Jinan Automatic Transmission三菱：TC-SST双离合器变速箱Mitsubishi: TC-SST dual clutch gearbox其实三菱SST双离合变速箱在工作原理上也是和DSG非常相似的，也同样是在奇数挡位和偶数挡位上各采用一个离合器，两个离合器会在同一时间各选择一个档位。这样一来，汽车在脱离一个档位后自动挂上下一档，其换档速度远远快于手动操作速度，从而缩短了换档延迟和动力损失。除换档更加平稳外，TC-SST还提高了EVO的加速度。

　　In fact, the working principle of Mitsubishi SST double clutch gearbox is very similar to DSG. It also uses one clutch in odd and even gears, and two clutches will choose one gear at the same time. In this way, the automobile automatically hangs up and down after leaving a gear. Its shift speed is much faster than the manual operation speed, thus reducing the shift delay and power loss. In addition to shifting more smoothly, TC-SST also improves EVO acceleration.