## Electric Traction: Buck and Boost Method of Speed Control of Traction Motors

Updated on 19-May-2022 12:12:36
The circuit diagram of the buck and boost method of speed control of traction motors is shown in the figure.There are two traction motors viz. traction motor-I and traction motor-II. In this method of speed control, the armature of both the traction motors I and II and the motor-generator set are connected in series. This whole series combination is connected across the main supply.When the terminal voltage of the generator is equal to the supply voltage in magnitude but of opposite polarity and the main contactor (MC) is closed, the voltage across the traction motors will be zero and hence ... Read More

## What are the auxiliary equipment used in an electric locomotive?

Updated on 19-May-2022 12:09:41
In addition to the main traction motors, the following additional equipment are required to be installed on an electric locomotive engine −Motor-Generator SetBatteryPantograph Operating EquipmentAir CompressorTraction Motor BlowersHeating EquipmentLet's check the functions of each of these equipment in detail.Motor–Generator SetThe motor-generator set used in the electric locomotives is of the two bearing type and it consists of a series motor and a shunt generator. The speed of the series motor at light load is limited by the ventilating fan and the voltage of the generator is controlled by an automatic voltage regulator (AVR).The generated voltage by the motor-generator set is ... Read More

## Electric Traction: Calculation of Sag and Tension for Trolley Wire

Updated on 19-May-2022 12:04:54

## Crest Speed, Average Speed & Schedule Speed of an Electric Train

Updated on 03-May-2022 08:12:02
Crest Speed of Electric TrainThe maximum speed attained by an electric train during running is termed as its "crest speed". It is denoted by Vm.Average Speed of Electric TrainAverage speed is defined as the mean of the speeds attained by the electric train from start to stop. In other words, average speed is defined as the ratio of the distance covered by the train between two stops to the actual time of run. The average speed of train is denoted by Va and is given by, $$\mathrm{\mathrm{Average\: speed, }V_{a}\:=\:\frac{\mathrm{Distance\: between \:two\: stops\: (\mathit{D})}}{\mathrm{Actual\: time\: of\: run (\mathit{T_{\mathrm{run}}})}}\:\mathrm{kmph}}$$Schedule Speed of Electric ... Read More

## General Features of Traction Motors: Mechanical Features & Electrical Features

Updated on 28-Apr-2022 08:43:11
An electric motor which is used to provide the primary rotational torque to a machine such as electric locomotives, elevators, conveyors, trolley buses and other electric vehicles etc. is described as a traction motor.General Features of Traction MotorsThe general features of the electric motors used for traction purpose are classified into two classes as −Mechanical FeaturesElectrical FeaturesMechanical Features of Traction MotorsThe mechanical features of electric motors used for traction applications are listed below −Robustness - A traction motor must be mechanically strong and robust so that it can be capable of withstanding severe mechanical vibrations.Small Size - The overall dimensions ... Read More