dwa meaning in English

空气钻井

Abstract : the basic circuit principle of ac drive traction converters is introduced , whose technical characteristics and development process are also described in details combinating the main parameters of traction converters for ac drive locomotives , such as dj electric locomotive , nj1 diesel locomotive and dwa metro engineering machine
文摘:阐述了交流传动牵引变流器的基本电路原理，结合国产dj型电力机车、 nj1型内燃机车、 dwa型地铁工程车等交流传动机车牵引变流器的主要技术参数，对交流传动牵引变流器的技术特点及其发展过程作了较为详细的叙述。