Address:84, D. Guramishvili Ave.,
Tbilisi, Georgia, 0141
6Е1 electric locomotive
To increase the railway throughput capacity, two variants of a heavy-duty electric locomotive with advanced traction and braking features are proposed.
Variant 1 The electric circuit has been developed through series excitation of traction motors in the traction mode and separate excitation in the regenerative braking mode, with excitation windings supplied from a static converter. This electric loco is conventionally designated as 6E1.
Variant 2 The electric circuit has been developed through mixed excitation of traction motors with current supply and control from a static converter, and in the regenerative braking mode – with separate excitation and traction motor excitation windings supplied from a static converter.
In the traction mode, in case of a static converter failure, the electric circuit switches traction motors to series connection and electric locomotive movement without excitation current regulation. This locomotive is conventionally marked as 6E1c.
Further description of both locomotives is identical, so only one loco will be described in this text.
The locomotive has one section. The section contains equipment which ensures operation in modes of traction and braking with control from either cab.
The locomotive bogies are two-axle, without pedestals, bogie frames are welded, the bogie brake system is provided through bilateral pressing of brake shoes. Wheel sets are fitted with devices to pass the current back which was taken by the locomotive from the catenary .
The body consists of a single semistreamlined section. The locomotive houses two driving cabs. Transmission of traction and braking efforts from a bogie to the body is effected through tilting tractions. The body is connected with bogies through bolster suspension. A track cleaner is mounted on the front buffer beam of the body frame. Demountable hatch tops are provided for mounting and dismantling of the body equipment on the locomotive roof. A headlight and a couple of dichromatic buffer lamps are mounted on the locomotive head-on part.
The body design eliminates the possibility of dust, snow and water penetration via air intake devices or other ways.
The locomotive is equipped with: pneumatic, automatic and auxiliary locomotive brakes, two compressors of ПК-3,5 series , each having maximum output
Forced air supply is provided for complete use of power and normal operating conditions for traction motors, compressor motors, triggering resistors, excitation attenuation resistors and induction shunts.
Air supply for ventilation is provided by two centrifugal fans with two exhaust pipe branches to cool traction motors and triggering resistors.
Air for cooling is taken from a premix chamber zone through the labyrinth louver arranged on the body walls. Air intake system provides two steps for control of cooling air supply which is attained by switching of fan gears from series connection to parallel and back.
Each driving cab contains the locomotive controls: the driver’s and assistant driver’s up-to-date instrument panel with the built-in compact controller, control-and-measuring devices, safety and signalling equipment. The cab has two seats for a driver and an assistant driver and electric heaters.
Head-on windows are furnished with windshield wipers which have pneumatic drive and built-in electric heaters.
In particular, the processor master system (M1 and M2), a push-button switch (SS1 and SS2), measuring devices, a display and locomotive controllers (R1, C1) are arranged in A and B cabins.
Each instrument unit with main controls for the locomotive electric equipment is furnished with functional units for operational control SL and measuring and control system CCM. Being arranged in the driving cab and on the instrument unit, functional units of microprocessor control system are linked through three-wire communications interface.
To operate the locomotive, the driving cab is furnished with controller handles:C1 – to operate the power mode and R1 – to operate the regenerative mode.
Locomotive electric circuits are effected through push-button switches SS1 and SS2. The operation of locomotives in multiple is provided through interface and is possible from either cab.
In case of A cab master M1 failure , automatic switching to M2 is ensured, which is arranged in B cab.
Advantages of microprocessor control system with application of interface channel:
1. There is no necessity in low voltage contact interlocks and interstitial relays (the number of contacts is over 150, and the number of relays is 10).
2. The economy of locomotive low-voltage wires is about 2000m.
3. The master controller with its more than 40 contacts is replaced by a miniature contactless control device.
4. Possibility to backup control devices.
5. Possibility of locomotive control circuits diagnostics at the driving cab.
6. Possibility to automate the locomotive operation.
7. The locomotive operation procedure is changed by microprocessor software updating.
Traction motors ТЛ-6 with power rating 810 kVt ( developed by TELP) are mounted on the locomotive.
Three connections of traction motors are provided for traction: in series, in series and parallel and in parellel.
For regenerative braking three connections of traction motors are also provided. Deceleration is changed through current control in main poles of traction motors.
Speed triggering and control are provided by:
a) gradual change of triggering resistor ratings in traction motor circuit;
b) regulation of magnet flux of traction motor main poles;
c) switching of traction motor connections.
Induction shunts prevent from inrush current in the traction motor circuit in unsteady processes for traction as well as for regeneration.
The electric circuitry ensures failure-free operation of the locomotive in such cases of emergency as: when the traction motor is laid up and in remote disconnection of two traction motors in series the locomotive is operated through four electric motors in series; in case of series and parallel connection – through three electric motors and four traction motors in parallel.
Regenerative braking of the locomotive with disconnected traction motors or static converters supplying excitation windings is excluded.
The pantograph operation routine eliminates:
a) possibility to lower powered pantographs;
b) possibility to raise the pantograph if the master controller position is other but zero.
The locomotive circuitry ensures the following types of protection for equipment
with the appropriate control and signal system:
a) against short- circuit current of traction motors with the help of БВП-5 high-speed circuit breaker and auxiliary machines and electric heaters with the help of БВЗ-2 high-speed circuit breaker;
b) against overloading through maximum current relays which signal traction motor overloading;
c) in case of overruns on traction motor collectors and earthing – through differential relays which ensure disconnection of the automatic high-speed circuit breaker;
d) against atmospheric and commutation voltage surge through dischargers and filters;
e) against slipping and skidding of wheel sets through appropriate sensors and relays;
f) against short- circuit currents of traction motors with the help of БК high-speed contactor in the regenerative regime.
g) against short circuits in lighting and signalling circuits with the help of automatic breakers and safety devices.
The locomotive movement, testing of auxiliary equipment and charging of storage batteries under shed conditions are provided through power supply using special sockets.
Low- voltage circuits are powered from dc power sources at 50V working voltage. The alkaline storage battery and control generators serve as dc power sources.
If supply voltage from the control generator is cut off, automatic switching of control circuit feeding to the storage battery is provided.
Interaction of electric and pneumatic brakes is provided as follows:
a) in case of the effect of regenerative braking deceleration of the locomotive by pneumatic brakes is ruled out;
b) in case of the stall of regenerative braking deceleration is attained through pneumatic braking of the locomotive irrespective of the handle position of brake valves.
The locomotive section is fitted with two pantographs.
To ensure safety for the maintenance personnel, the locomotive is furnished with interlocks for the high-voltage cell, roof and driver’s panel equipment as well as with appropriate caution plates.
Upon a customer’s request it is possible to furnish the cab with the air-conditioner.
Advantages of the proposed locomotive as compared with ВЛ8 locomotive.
1. At speed 100km/h and in complete field of traction motors, 6Е1 locomotive tractive effort is 53,5 kN which is 41% more than in ВЛ8 – 21,6kN, and at stage 3 of traction motor field attenuation (FA3) the difference in tractive effort is increased up to 51%( 6E1 – 133kN, ВЛ8 – 68,7kN).
2. Transmission of tractive and braking efforts from the bogie to the body through tilting tractions improves locomotive coupling properties by 5%, as well as dynamics of locomotion , excluding the necessity to use a wheel-set anti-unloading system.
3. Application of a static converter for feeding of traction motor excitation windings makes it possible to form desired brake properties and ensures smooth control of tractive effort.
4. Static converters are made on the basis of IGBT transistors, with microprocessor control, that enables full diagnostics of possible troubles.
5. Air supply change ensures realization of power increase of traction motors and triggering resistors.
6. ПК3,5 compressor is used having less weight and smaller vibration in comparison with KT6 compressor.
7. Application of БВЗ-2 high-speed circuit breaker improves protection of power auxiliary circuits.
8. Application of an up-to-date panel increases ergonomics and comfortable conditions of the driver’s work.
The main distinction of the mechanical part is as follows: in ВЛ8 spring suspension is single-stage ( the body rest on the bogie is rigid), transmission of tractive effort from wheel sets to automatic coupling is provided through sliding guiding journal-boxes and articulated bogie frames, but in the proposed six-axle locomotive spring suspension is two-stage, transmission of tractive effort from wheel sets to automatic coupling is provided through resilient journal-box guides, inarticulate bogie frames, tilting tractions and the locomotive body.
The aforesaid determines considerably smaller influence of the locomotive on the track. For this reason, ВЛ8 locomotive peak speed with the thrust 22,5 tons was restricted to