1. Working Principle of Dual Clutch Automatic Transmission雙離合自動變速器（簡稱DCT）基于手動變速箱基礎之上。而與手動變速箱所不同的是，DCT中的兩幅離合器與二根輸入軸相連，換擋和離合操作都是通過一集成電子和液壓元件的機械電子模塊來實現。而不再通過離合器踏板操作。就像tiptronic液力自動變速器一樣，駕駛員可以手動換擋或將變速桿處于全自動D擋（舒適型，在發動機低速運行時換擋）或S擋（任務型，在發動機高速運行時換擋）模式。此種模式下的換擋通常由擋位和離合執行器實現。兩幅離合器各自與不同的輸入軸相連。如果離合器1通過實心軸與擋位1、3、5相連，那么離合器2則通過空心軸與擋位2、4、6和倒擋相連。 雙離合變速箱通俗的說就是，這種變速速箱形式就有兩個離合器，一個控制1、3、5檔，一個控制2、4、6檔。使用一檔的時候二檔已經準備好了，同理，所以換檔時間大大縮短，沒有延時。

　　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、市面上常見的幾種雙離合自動變速器形式：

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

　　大眾：DSG雙離合器變速箱

　　Volkswagen: DSG Dual Clutch Gearbox
                    

　　很多國人對于雙離合變速器的認識也是從DSG開始。當然，大眾的“雙離合”也是比較有代表性的，旗下大部分進口車也都配有DSG，如高爾夫GTI，EOS，邁騰和尚酷等。 大眾EOS采用的就是DSG雙離合變速箱不過，現今大眾其實共有兩款DSG雙離合變速器，在大眾內部代號分別為DQ250和DQ200，從直觀數據上分析，代號DQ250的DSG有六個擋位，能承受較大扭矩為350NM，主要用于高排量或主打操控性的車型，如高爾夫GTI和即將上市的09款邁騰；而DQ200則是七速雙離合變速器，能承受較大扭矩為250NM，主要搭載于中低排量的車型，如下半年上市的高爾夫6、速騰等。

　　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.

　　沃爾沃：POWERSHIFT雙離合器變速箱

　　Volvo: POWERSHIFT Dual Clutch Gearbox

　　與大眾所采用的干式離合器的DSG變速箱不同，Powershift所采用的是濕式雙離合器，是將離合器片浸泡在機油當中，來對其進行冷卻。離合器可以將動力輸送給六個檔位中的任何一個，由電腦控制的離合器根據汽車速度和轉速對駕駛者的換檔意圖做出判斷，可以預選擇下一擋位從而實現檔位的快速切換。 POWERSHIFT雙離合器變速箱[3] 由于Powershift變速箱可以設定在電腦控制的“自動”模式之下，或者利用方向盤上的撥片來實現手動換檔。搭載2.0升四缸渦輪柴油的C30、S40和V50是首批配備這種變速箱的車型。雖然這臺發動機的較大功率和扭矩分別為136馬力和320牛米，但這種雙離合變速箱可承受的較大扭矩輸出達到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.

　　保時捷：PDK雙離合器變速箱

　　Porsche: PDK Dual Clutch Gearbox

　　PDK雙離合器變速箱其原名為保時捷Doppel Kupplungen，當然就是雙離合器變速系統的德文，而PDK便是取名自德文原名中三個單字的前綴字母的組合。根據消息顯示，這個全新的雙離合器變速系統工作原理與VW集團的DSG相同，也同樣具備附在方向盤后方的換檔撥片，讓駕駛者手不需離開方向盤就可以進行換檔控制的功能。 保時捷——PDK雙離合器變速箱PDK雙離合器變速箱同樣具備兩組離合器，分別負責奇數與偶數檔位，換檔速度要比現在大多數普通的手排變速箱快很多，保時捷的大多數車款將把這個雙離合器變速箱作為選購配備。

　　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雙離合器變速箱Mitsubishi: TC-SST dual clutch gearbox其實三菱SST雙離合變速箱在工作原理上也是和DSG非常相似的，也同樣是在奇數擋位和偶數擋位上各采用一個離合器，兩個離合器會在同一時間各選擇一個檔位。這樣一來，汽車在脫離一個檔位后自動掛上下一檔，其換檔速度遠遠快于手動操作速度，從而縮短了換檔延遲和動力損失。除換檔更加平穩外，TC-SST還提高了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.