Evolution of Electrical Rolling Stock
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Questions and Answers

What was a significant factor that allowed for the large-scale application of single phase 50Hz 25kV for mainline electrification?

  • Import of Japanese locomotives
  • Advancements in AC traction technology
  • Use of high-speed DC motors
  • Development of mercury arc rectifiers (correct)

Which type of rectifier offered an additional advantage of reversibility?

  • Mercury arc rectifiers
  • Excitrons (correct)
  • Thyristor converters
  • Silicon rectifiers

What is primarily used for voltage control in locomotives with mercury arc and silicon rectifiers?

  • Digital controllers
  • Electro-pneumatically operated tap changers (correct)
  • Phase angle switches
  • Manual switches

What was a notable feature of the silicon diode devices in modern AC locomotives?

<p>They are simple to maintain and extremely reliable (C)</p> Signup and view all the answers

Which locomotives were mentioned as employing silicon rectifiers for conversion?

<p>WCAM-1 and YAM-1 (D)</p> Signup and view all the answers

What advantage do thyristor converters have over silicon rectifiers in certain WAG-1 and WAM-2 locomotives?

<p>Phase angle control (A)</p> Signup and view all the answers

In comparison to DC locomotives, what significant benefit do AC locomotives provide?

<p>Increased reliability in performance (B)</p> Signup and view all the answers

What component is responsible for taking supply current from the overhead conductor?

<p>Pantograph (C)</p> Signup and view all the answers

Which of the following components is connected to the high-voltage end of the transformer primary winding?

<p>Lightning arrestor (A), Earth switch (D)</p> Signup and view all the answers

What is the purpose of the primary-overload relay?

<p>To protect the main transformer (A)</p> Signup and view all the answers

Which component is primarily responsible for providing surge suppression in the rectifier case?

<p>Surge-suppression fuses (A)</p> Signup and view all the answers

Where is the earth cable connected in relation to the traction motors?

<p>To the axle earth-brushes (C)</p> Signup and view all the answers

What is the primary purpose of the grounding transformer (GT) in the main circuit?

<p>To ensure the current returns to the earth via the wheels and rails. (A)</p> Signup and view all the answers

How are the traction motor modules controlled in the main circuit?

<p>Individually, depending on adhesion conditions. (C)</p> Signup and view all the answers

What does the term 'overlapping control' refer to in the context of the convertors?

<p>Gradual firing of the thyristors in sequence. (B)</p> Signup and view all the answers

What do the LC-links connected parallel to each traction winding achieve?

<p>They control the power factor and smoothen current flow. (D)</p> Signup and view all the answers

What type of motors are used in the traction system as specified in the document?

<p>Separately excited dc motors with bogie suspension. (D)</p> Signup and view all the answers

Which component rectifies the 50 Hz supply voltage before it is fed to the traction motors?

<p>Convertors consisting of thyristors and diodes. (D)</p> Signup and view all the answers

What role does the power factor control equipment (PFC) play in the system?

<p>It minimizes harmonics introduced by the phase angle control. (A)</p> Signup and view all the answers

What happens to the power delivered to the motors during acceleration according to the document?

<p>Only one bridge is fired until it is fully advanced. (C)</p> Signup and view all the answers

What does the smoothing reactor do in each motor circuit?

<p>It smooths the current from the convertors. (A)</p> Signup and view all the answers

What happens if an over current occurs on any of the monitoring transformers?

<p>The main circuit breaker will open immediately. (A)</p> Signup and view all the answers

What is the purpose of the potential transformer (PT) in the system?

<p>To monitor the supply voltage. (A)</p> Signup and view all the answers

What method is used to enable the driver to discover faults and possibly reset them from the cab?

<p>Computerized fault indicating system (FIS). (D)</p> Signup and view all the answers

How is the current from the overhead line processed in the main circuit?

<p>It passes through the main circuit breaker to the primary winding of the main transformer. (B)</p> Signup and view all the answers

What type of control is employed during the acceleration phase of the convertors?

<p>Overlapping control. (B)</p> Signup and view all the answers

What is the function of the smoothing reactors in the circuit?

<p>They provide a steady current flow to the traction motors. (D)</p> Signup and view all the answers

What effect does phase angle control of the thyristors have on power quality?

<p>It introduces harmonics and varies power factor and psophometric current. (D)</p> Signup and view all the answers

What is the role of the power factor control equipment (PFC)?

<p>To minimize the influence of harmonics on the supply network. (A)</p> Signup and view all the answers

How is the traction motor armature circuit organized?

<p>Into two groups of three traction motors each. (B)</p> Signup and view all the answers

What is the electrical characteristic of the convertors regarding free wheeling current?

<p>They provide a path for free wheeling current when thyristors are not fired. (B)</p> Signup and view all the answers

What is the approximate ratio of separate field strength to series field strength in traction motors?

<p>60:40 (D)</p> Signup and view all the answers

How are the traction motors suspended in WAG-6B and WAG-6C models?

<p>Fully suspended in WAG-6B, nose-suspended in WAG-6C (C)</p> Signup and view all the answers

During acceleration, how is the field current managed until maximum motor voltage reference is achieved?

<p>It is increased proportionally with armature current. (B)</p> Signup and view all the answers

When does the first power factor correction (PFC) unit switch on?

<p>When the primary current reaches 100A. (C)</p> Signup and view all the answers

What device is used to limit the maximum voltage over the main transformer to curb over voltage?

<p>Lightning arrestor (C)</p> Signup and view all the answers

What happens when an over current occurs on any of the monitoring transformers?

<p>The main circuit breaker (MCB) opens immediately. (D)</p> Signup and view all the answers

What is the primary role of the potential transformer (PT) in the safety monitoring system?

<p>To monitor supply voltage levels. (D)</p> Signup and view all the answers

What is the purpose of the computerized fault indicating system (FIS) in the traction motor setup?

<p>To supervise running conditions and indicate faults. (A)</p> Signup and view all the answers

What defines the braking characteristics during rheostatic breaking?

<p>Field current is reduced based on required braking characteristics. (C)</p> Signup and view all the answers

What is the role of current transformers (CT) in the safety monitoring system?

<p>To continuously monitor the current in all windings. (A)</p> Signup and view all the answers

Which component is primarily responsible for protecting the main transformer from overload conditions?

<p>Primary-overload relay (A)</p> Signup and view all the answers

What is the function of the lightning arrestor in the electric traction context?

<p>To divert excess voltage surges away from electrical components (C)</p> Signup and view all the answers

Which component connects to the insulated earth cable to facilitate the return circuit to the running rails?

<p>Traction motors (A)</p> Signup and view all the answers

Which of the following components is NOT associated with the rectifier case?

<p>Motor overload relays (D)</p> Signup and view all the answers

What role does the high-voltage end of the transformer serve regarding other components?

<p>Connects to the lightning arrestor and provides surge protection (C)</p> Signup and view all the answers

What technological advancement in rectifiers significantly improved the performance of AC locomotives over DC counterparts?

<p>High Power Silicon Diode Devices (A)</p> Signup and view all the answers

What is the primary factor that allowed for better reliability in newer rectifiers used in locomotives?

<p>Silicon rectifiers (D)</p> Signup and view all the answers

In which locomotives was the phase angle controlled thyristor converter notably implemented as a replacement?

<p>WAG-1 and WAM-2 (D)</p> Signup and view all the answers

Which type of control mechanism is used for voltage adjustment in locomotives utilizing mercury arc and silicon rectifiers?

<p>Electro-pneumatically operated tap changers (C)</p> Signup and view all the answers

Which class of locomotives uses silicon rectifiers and operates in a single isolated section?

<p>YAM-1 (D)</p> Signup and view all the answers

What was a disadvantage of AC traction motors compared to their DC counterparts before advancements in technology?

<p>Inferior performance (D)</p> Signup and view all the answers

What additional functionality do excitrons provide over the earlier mercury arc rectifiers?

<p>Ability to convert AC back to DC (C)</p> Signup and view all the answers

Which drive arrangement is utilized in WAM2 and WAM3 locomotives?

<p>WN coupled gear drive (C)</p> Signup and view all the answers

What is the starting tractive effort of monomotor bogie locomotives mentioned in the content?

<p>32 tonnes (A)</p> Signup and view all the answers

Which design of bogie is used in the indigenous WAG5 locomotives?

<p>Trimount bogies of ALCO design (A)</p> Signup and view all the answers

What unique feature does the WAG-6A locomotive utilize for its drive system?

<p>ASEA hollow shaft drive system (D)</p> Signup and view all the answers

What type of bogie modification is included in the WAP-1 locomotives?

<p>Flexicoil bogie (C)</p> Signup and view all the answers

How many axles do the WAG-6 locomotives have to achieve high tractive efforts?

<p>6 axles (B)</p> Signup and view all the answers

Which class of locomotives was primarily manufactured at Chittranjan Locomotive Works until the early seventies?

<p>WAG 1 and WAG 4 (D)</p> Signup and view all the answers

What is the design characteristic of the bogies used in WAG-6B locomotives?

<p>Bogie with high adhesion (D)</p> Signup and view all the answers

What limitation is noted concerning the starting tractive effort of locomotives in the context provided?

<p>Limited by bridge capacity to 37.5t (B)</p> Signup and view all the answers

What action does the main circuit breaker (MCB) take when an over current is detected in the monitoring transformers?

<p>It opens immediately. (A)</p> Signup and view all the answers

How does the computerized fault indicating system (FIS) assist the driver during operation?

<p>It offers real-time monitoring and fault reset capability from the cab. (D)</p> Signup and view all the answers

During the acceleration phase of the locomotives, what is unique about the firing sequence of the convertors?

<p>Only one bridge is fired initially, followed by the other just before full acceleration. (D)</p> Signup and view all the answers

What are smoothing reactors used for in the circuit?

<p>To provide a steady current to the traction motors. (A)</p> Signup and view all the answers

What is the main benefit of using power factor control equipment (PFC) in the system?

<p>It enhances the overall efficiency by reducing harmonics. (A)</p> Signup and view all the answers

What does overlapping control of thyristors accomplish during locomotive acceleration?

<p>It allows for efficient management of electrical load. (C)</p> Signup and view all the answers

Which component is primarily responsible for monitoring the supply voltage in the system?

<p>Potential transformer (PT) (D)</p> Signup and view all the answers

How is the traction motor armature circuit organized in the WAG-6B/WAG-6C models?

<p>Divided into two groups of three traction motors each. (B)</p> Signup and view all the answers

What happens if the potential transformer (PT) detects an abnormal supply voltage?

<p>It triggers an immediate opening of the MCB. (D)</p> Signup and view all the answers

During which conditions might the driver use the push button in the driver's cab?

<p>To reset most faults indicated by the FIS. (C)</p> Signup and view all the answers

What is the maximum haulage capacity for passenger services at 60 km/h on a 1/200 grade?

<p>1215 tonnes (A)</p> Signup and view all the answers

Which grade requires the least amount of haulage capacity for a starting service according to the provided data?

<p>1/50 (A)</p> Signup and view all the answers

At what speed does the maximum haulage capacity for coaching stock drop below 500 tonnes?

<p>110 km/h (C)</p> Signup and view all the answers

What haulage capacity is listed for freight service at a grade of 1/150 for speeds of 90 km/h?

<p>830 tonnes (C)</p> Signup and view all the answers

For a service grade of 1/100, at what speed does the haulage capacity for ICF reach 600 tonnes?

<p>90 km/h (C)</p> Signup and view all the answers

Which of the following is NOT an indicated maximum haulage capacity for passenger services at 40 km/h?

<p>1010 tonnes (B)</p> Signup and view all the answers

What is the maximum haulage capacity for service stock at a grade of 1/200 and speed of 120 km/h?

<p>715 tonnes (C)</p> Signup and view all the answers

At 110 km/h, what is the maximum haulage capacity for a service on a grade of 1/150?

<p>710 tonnes (A)</p> Signup and view all the answers

Which speed corresponds to the maximum haulage capacity of 4340 tonnes at level grade?

<p>60 km/h (B)</p> Signup and view all the answers

For a coaching stock at 1/50 grade, what is the maximum haulage capacity at 80 km/h?

<p>490 tonnes (A)</p> Signup and view all the answers

Flashcards

Mercury arc rectifier

An older type of rectifier used in early electric locomotives, utilizing mercury vapor to convert AC to DC.

Excitron

A type of externally fired, air-cooled rectifier, replacing water-cooled mercury arc rectifiers.

Silicon rectifier

A modern rectifier, using semiconductor diodes for efficient AC to DC conversion.

AC traction motor

A motor that runs on alternating current electricity.

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DC traction motor

A motor that runs on direct current electricity.

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Voltage control (in locomotives)

Adjusting the electrical voltage supplied to the traction motors in electric locomotives.

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Tap changer

A device that adjusts the voltage in a power system.

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MG locomotives

Electric locomotives utilizing silicon rectifiers.

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WAG-6A Main Circuit

The electrical system in a WAG-6A locomotive that carries power from the overhead line to the traction motors.

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25 kV 50 Hz Overhead Line

The source of electrical power for the locomotive, utilizing a high voltage AC system.

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Grounding Transformer (GT)

In the locomotive's main circuit, it ensures current flows through the wheels and rails to the ground.

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Traction Motor Modules

Parts of the locomotive's main circuit that control the power to individual traction motors.

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Convertors

Electrical components that rectify (change) the AC power from the overhead line to DC power to run the traction motors.

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Overlapping Control

A method in the convertors to smooth the current flowing to the motors, and control the acceleration/deceleration.

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Power Factor Control (PFC)

Equipment used to minimize variations in power factor and psophometric current generated by the convertors on the locomotives electrical network.

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Traction Motors

Electric motors that provide the locomotive's tractive effort (force) to move the train.

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Separately Excited DC Motors

DC motors used in locomotives where the field current is independent of the armature current. Improves efficiency.

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Smoothing Reactor

A component in series with each motor in the locomotive, used to smooth the current generated by the convertors.

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Main Circuit Breaker (MCB)

A safety device that opens the circuit in case of an overload or fault in the electrical system.

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Potential Transformer (PT)

A transformer used to measure voltage in an electrical system.

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Computerized Fault Indicating System (FIS)

A system that detects and displays fault conditions in a locomotive.

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Microprocessor (in FIS)

The "brain" of the FIS, supervising running conditions.

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Overhead Line

The electrical supply line above the train.

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Pantograph

A mechanical device that collects power from the overhead line.

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Main Transformer

The transformer that converts electrical power from the overhead line.

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Traction Motor Groups

Groups of motors that drive the locomotive.

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Convertors

Electronical components that change alternating current (AC) to direct current (DC).

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Thyristors and Diodes (in convertors)

Components that control current flow in convertors.

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Overlapping Control

Technique used by convertors to accelerate, by firing both thyristor bridges progressively.

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Power Factor Control Equipment (PFC)

Equipment that ensures the locomotive's power usage aligns with the supply network's needs.

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Harmonics

Unwanted components in Alternating Current (AC) power.

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Traction Motors

Compound wound motors in electric locomotives, with a specific field strength ratio (approximately 60:40 separate to series).

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WAG-6B Suspension

A type of locomotive suspension system where the traction motors are fully suspended.

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WAG-6C Suspension

A type of locomotive suspension system where the traction motors are nose-suspended.

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Field Convertor

A device that controls the field current in traction motors, crucial for acceleration and braking.

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Field Current Control

Adjusting the field current to match the required motor characteristics during acceleration and braking.

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Power Factor Correction

A system that improves the power factor of electric locomotives using LC-links switched by thyristors.

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PFC Unit Switching

Switching on/off additional power factor correction units to compensate for changing primary current.

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Safety Monitoring

Continuous monitoring of currents (all windings and motor fields, main transformer) through current transformers (CT).

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Fault Detection System

A computerized system using a microprocessor that monitors all running conditions, indicating and reporting faults or problems to quickly inform the driver.

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Main Circuit Breaker (MCB)

A safety device that opens the main circuit to protect the locomotive, triggered by overcurrent conditions.

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Rectifier Case

Component housing surge-suppression equipment and thyristors in AC traction systems.

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LA (Lighting Arrestor)

Device protecting equipment from lightning surges on the roof of the locomotive.

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M1-4 (Traction Motors)

Electric motors driving the locomotive's wheels, located on the bogies.

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MC1-4 (Motor Contactors)

Switching devices controlling the flow of electricity to traction motors.

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MOR1-2 (Motor Overload Relays)

Safety devices that disconnect power if motor current exceeds a safe limit.

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MT (Main Transformer)

Transforms high voltage AC power into lower voltage power for the locomotive.

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P (Pantograph)

Device that collects electrical power from overhead lines.

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POCT (Primary Overload Current Transformer)

Transformer used with the primary overload relay to detect excessive current in the primary circuit.

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POR (Primary Overload Relay)

Safety device that disconnects power based on high current in the primary circuit.

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SOCT (Secondary Overload Current Transformer)

Transformer used to monitor current in the secondary circuit of an AC traction system.

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SOR (Secondary Overload Relay)

Safety device in the secondary circuit, protecting equipment from overload.

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SSF1-4 (Surge-suppression Fuses)

Safety devices that protect against surges in the rectifier circuit.

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SSK1-4 (Surge-suppression Capacitor)

Capacitors used to suppress voltage surges in the rectifier circuit.

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SSR1-2 (Surge-suppression Relay)

Protection device that acts to interrupt current flow in the event of a surge.

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SST1-2 (Surge-suppression Transformer)

Transformer designed to suppress voltage surges within the rectifier circuit.

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SSZ1-4 (Surge-suppression Resistor)

Resistors used to dissipate excess surge energy and lessen the effect of voltage spikes.

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SX1-4 (Smoothing Inductor)

Inductor that smooths out fluctuations in the DC output of the rectifier.

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T1-4 (Thyristors)

Semiconductor devices that control the flow of electricity in AC traction systems.

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WSR1-2 (Wheel Slip Relays)

Devices that detect wheel slip to prevent damage to the traction motors.

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WSZ1-4 (Wheel Slip Resistor)

Resistors that dissipate energy in the event of wheel slip.

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Mercury Arc Rectifier

An older type of rectifier, using mercury vapor to convert AC to DC. Used in older locomotives

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Excitron

Air-cooled rectifier, replacing water-cooled mercury arc rectifiers for better reliability.

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Silicon Rectifier

Modern rectifier using diodes for efficient AC-DC conversion. Reliable and powerful

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AC Traction Motor

Motor operating on alternating current (AC).

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DC Traction Motor

Motor that runs on direct current (DC).

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Voltage Control (in locomotives)

Adjusting the electrical voltage supplied to the traction motors.

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Tap Changer

Device to adjust voltage levels in a power system.

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MG locomotives

Electric locomotives using silicon rectifiers.

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25 kV 50 Hz Overhead Line

Source of high-voltage AC power for electric locomotives.

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Convertors

Electrical components changing AC to DC for traction motors.

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Haulage Capacity

The maximum load a locomotive can pull at different speeds and grades.

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Level Grade

A flat track with no incline or decline.

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1/500 Grade

A track that rises or falls by 1 unit for every 500 units of horizontal distance.

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Tonnes at km/h

The weight a locomotive can pull at a specific speed on a given grade.

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WAP 1 Locomotive

A specific type of electric locomotive.

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Tangent Track

A straight section of railway track.

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Starting T.E.

Initial tractive effort of the locomotive.

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Locomotive Types

Different types of locomotives with various driving mechanisms like cordon shaft drive, coupled gear drive, monomotor bogie, etc.

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WAM1 Drive

A locomotive type using a cordon shaft drive system.

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WAM2 and WAM3 Drive

Locomotives using WN coupled gear drive.

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WAG (1, 3, and 4) Drive

Locomotives using a coupled gear drive system through a cordon shaft monomotor bogie.

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WAG2 Drive

Locomotive with a monomotor bogie and flexible rubber couplings (quill drive).

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Monomotor Bogie Tractive Effort

Starting tractive effort of locomotives with monomotor bogies was approximately 32 tonnes with 790 HP motor power per axle.

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WAG 1 & 4 Loco Manufacturing

A significant portion of WAG1 and WAG4 class locomotives were manufactured at Chittranjan Locomotive Works (CLW) up to early 1970s.

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WAG 5 Loco Bogie

A locomotive type (WAG 5) that utilized Co-Co, tri-mount bogies of ALCO design with axle-hung nose-suspended traction motors.

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WAG-6A/B Loco Feature

WAG-6A and WAG-6B locomotives aimed for high tractive effort and high speeds (above 160 km/h) by employing a 6-axle (Bo-Bo-Bo) arrangement.

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WAP-1 Bogie Modification

WAP-1 locomotives used Flexicoil bogie design, modifying the existing WDM-1 (General Motors design).

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Main Circuit Breaker (MCB)

A safety device that opens the circuit in case of overload or fault in the electrical system of a locomotive.

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Potential Transformer (PT)

A transformer used to measure voltage in an electrical system, often for monitoring purposes in locomotives.

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Computerized Fault Indicating System (FIS)

A system in a locomotive that detects and displays fault conditions, enabling the driver to reset faults from the cab.

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Microprocessor (in FIS)

The central processing unit of the FIS, supervising running conditions to monitor faults.

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Overhead Line

The electrical supply line above the train, providing power to the locomotive.

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Pantograph

A mechanical device that collects power from the overhead line and transfers it to the locomotive.

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Main Transformer

The transformer converting high-voltage AC power from the overhead line to lower voltage power for the locomotive.

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Traction Motor Groups

Groups of electric motors within a locomotive that drive the locomotive's wheels

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Convertors

Electrical components changing AC power to DC power that operates traction motors.

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Overlapping Control

A control method in convertors which involves progressively firing multiple thyristor bridges to control acceleration and deceleration smoothly.

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Power Factor Control (PFC)

Equipment used to control the variations in power factor and psophometric current generated by the convertors, ensuring they do not disrupt the supply system

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Traction Motors

Electric motors that provide the locomotive's tractive effort to move the train.

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Rectifier Case

A component housing surge-suppression equipment and thyristors in AC traction systems.

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LA (Lighting Arrestor)

A device on the locomotive roof that protects equipment from lightning surges.

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M1-4 (Traction Motors)

Electric motors driving the locomotive's wheels, located on the bogies.

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MC1-4 (Motor Contactors)

Switching devices controlling the flow of electricity to traction motors.

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MOR1-2 (Motor Overload Relays)

Safety devices that disconnect power if motor current exceeds a safe limit.

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MT (Main Transformer)

Transforms high voltage AC power into lower voltage power for the locomotive.

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P (Pantograph)

Device that collects electrical power from overhead lines.

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POCT (Primary Overload Current Transformer)

Transformer used with the primary overload relay to detect excessive current in the primary circuit.

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POR (Primary Overload Relay)

Safety device that disconnects power based on high current in the primary circuit.

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SOCT (Secondary Overload Current Transformer)

Transformer used to monitor current in the secondary circuit of an AC traction system.

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SOR (Secondary Overload Relay)

Safety device in the secondary circuit, protecting equipment from overload.

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SSF1-4 (Surge-suppression Fuses)

Safety devices that protect against surges in the rectifier circuit.

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SSK1-4 (Surge-suppression Capacitor)

Capacitors used to suppress voltage surges in the rectifier circuit.

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SSR1-2 (Surge-suppression Relay)

Protection device that acts to interrupt current flow in the event of a surge.

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SST1-2 (Surge-suppression Transformer)

Transformer designed to suppress voltage surges within the rectifier circuit.

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SSZ1-4 (Surge-suppression Resistor)

Resistors used to dissipate excess surge energy and lessen the effect of voltage spikes.

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SX1-4 (Smoothing Inductor)

Inductor that smooths out fluctuations in the DC output of the rectifier.

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T1-4 (Thyristors)

Semiconductor devices that control the flow of electricity in AC traction systems.

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WSR1-2 (Wheel Slip Relays)

Devices that detect wheel slip to prevent damage to the traction motors.

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WSZ1-4 (Wheel Slip Resistor)

Resistors that dissipate energy in the event of wheel slip.

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Study Notes

Evolution of Electrical Rolling Stock

  • Electrical locomotives use mercury arc rectifiers (initially water-cooled) to convert AC to DC, then later, air-cooled rectifiers (excitrons) for more reliable solutions.
  • Excitrons, a later solution, offered the advantage of reversibility, converting DC to AC for regeneration purposes.
  • With the development of high-power silicon diode devices, a significant advancement was made in the design of AC locomotives. Silicon diode technology is simpler to maintain and highly reliable.
  • The utilization of silicon rectifiers and a tap-changer controlled system for voltage regulation is now widely employed in Indian Railways' locomotive fleet.
  • Some locomotives use phase-angle-controlled thyristor converters for voltage control, replacing the older silicon rectifier setup.
  • Electrical multiple units (EMUs) and motor-generator (MG) locomotives also use silicon rectifiers for conversion in different sections.

Sources of Electric Locomotives

  • Indian Railways imported WAP-1 and WAP-3 locomotives (using Co-Co flexi-coil bogies for higher speeds).
  • WAG-1 and WAG-2 (higher adhesion mono motor bogies) locomotives were also imported.
  • Some locomotives have been manufactured at Chittaranjan Locomotive Works (CLW).
  • CLW has manufactured various series of locomotives including WAM-4 and WAG-5.

Mechanical Concepts

  • Different axle locomotive designs (WAM1, WAM2, WAM3, WAG1, WAG3, WAG4, WAG2) have utilized varied drive mechanisms (e.g., cordon shaft drive, coupled gear drive, monomotor bogies with flexible rubber couplings) for traction.
  • The performance of some locomotive designs (e.g., WAG1, WAG2, WAG3) was deemed inadequate for later requirements.

Diagrams and Layouts

  • Detailed diagrams provide layouts of equipment like master controllers, driver seats, and specific components like transformers, tap changers, and rectifiers for various loco types (WAM-1, WAM-2, WAP-1, WAG-5, WAG-6).
  • Data on components like transformers, rectifiers, and other vital equipment for different locomotive classifications (e.g., WAG 1, WAG 4, WAM 3), also provided in the appendix.
  • Diagrams of layouts within train units (e.g., the WAU-4 EMU) are included.
  • Diagrams are included for the power circuit in WAG-6A, including module disconnectors (MDs) between the convertors and the transformer.

Electrical Equipment

  • Detailed specifications such as type, gauge, dimensions, axle load, weight, bogie arrangement, traction motor, and brake systems are given for various types of locomotives.
  • Data on various components and configurations for locomotives from different manufacturers (e.g., Hitachi, ASEA) is included.
  • Components like braking systems, transformers, rectifiers, and switch arrangements are explained.

Power Factor Correction (PFC)

  • The PFC system is used in AC locomotive circuits to improve the power factor and reduce harmonics.
  • The system uses tuned LC-links to compensate for capacitive variations during operation.
  • An efficient PFC system is vital for the smooth running and performance of AC locomotives.

Safety and Fault Detection

  • Safety monitoring is managed using current transformers, breakers, and the main circuit breaker (MCB).
  • An indicating system (FIS) monitors operating conditions with displays in the drivers cabin.
  • Fault detection and troubleshooting capabilities of the systems used in AC locomotives are described.

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Related Documents

Indian Railways AC Traction Manual PDF

Description

Explore the advancements in electrical locomotives and their conversion technologies. This quiz covers the transition from mercury arc rectifiers to modern silicon diode devices, highlighting their significance in enhancing reliability and maintainability. Test your knowledge of electric locomotive systems used in railways.

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