Railway electric braking systems

The paper deals with electric braking systems on electrified railways where the braking effort is produced by traction motors acting as generators. Descriptions are given of the principal regenerative and rheostatic braking systems, together with their main characteristics. Considerations leading to the use and most suitable form of electric braking are discussed, and it will be observed that the ruling factors are economic ones. Locomotive-hauled trains and multiple-unit suburban motor-coach trains are treated separately as conditions are so radically different, and much greater space is devoted to locomotive-hauled trains as electric braking has been predominantly applied to them. The paper concludes by indicating how all the benefits of regenerative braking and efficient starting can be obtained with multiple-unit motor-coach trains without any addition to the motor-coach electrical equipment. The author´s experience indicates that electric braking, particularly regenerative braking, is readily justified for locomotive-hauled mainline trains where there is sufficient length of route with gradients, but that only abnormal circumstances can justify its use with multiple-unit suburban motor-coaches.