铁路牵引动力是完成铁路运输任务的关键技术设备。牵引动力的现代化又是铁路现代化的中心环节。世界各国不断以新型牵引动力来取代和淘汰旧的牵引动力,其原因就是新型牵引动力具有较好的经济效果。我国的牵引动力也在不断地进行改革。为了完成国家规定的、不断增长的运输任务,在所采取的技术措施中,就牵引动力而言,有机车类型的选择、机车性能的选择以及机车功率的选择。但是,牵引动力的改革必须取决于经济效果。目前评价经济效果,有下列一些主要指标: 一、投资效果系数 Railway traction power is the key technical equipment to complete the task of railway transportation. Traction of the modernization of power is the central part of railway modernization. All countries in the world continue to replace and eliminate the old traction power with new traction power. The reason is that the new traction power has a good economic effect. China’s traction is also constantly reforming. In order to complete the continually increasing transportation tasks prescribed by the state, among the technical measures taken, in terms of traction power, there are the types of locomotives to choose, the choice of locomotive performance and the locomotive power selection. However, traction reforms must depend on economic effects. The current evaluation of economic effects, there are some of the following main indicators: First, the investment effect coefficient