Auxiliary Converter Systems in Locomotives
80 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the function of the inductor in a three-phase system?

  • To increase the frequency of the output voltage
  • To regulate battery charging speed
  • To convert AC voltage to DC voltage
  • To attenuate harmonics and withstand load short-circuits (correct)

What does the term U1rms represent in relation to the motor's shaft power?

  • The fundamental component derived from the output voltage (correct)
  • The maximum voltage that the motor can handle
  • The total power consumed by the motor
  • The sum of all harmonic components of voltage

What is the purpose of the capacitor located on the charger circuit?

  • To amplify the current for more efficient charging
  • To increase the inverter frequency
  • To smooth out the charger voltage and limit transient voltage rise (correct)
  • To change AC voltage into DC voltage

Which values correspond to the operating conditions under steady state in an inverter?

<p>Frequency and amplitude consistently match the set point (B)</p> Signup and view all the answers

What does the battery charger circuit breaker protect against?

<p>Overload conditions (D)</p> Signup and view all the answers

What is the output frequency range for converters BUR1 and BUR2?

<p>0 to 50 Hz (A)</p> Signup and view all the answers

What is the rated output of the battery charger in the auxiliary converter system?

<p>111 V (B)</p> Signup and view all the answers

Which converter supplies the battery charger under normal operating conditions?

<p>BUR3 (C)</p> Signup and view all the answers

At what temperature will the fans inside the box start running?

<p>Above 50°C (A)</p> Signup and view all the answers

What is the purpose of the intermediate chokes in the system?

<p>To reduce the weight of the locomotive (D)</p> Signup and view all the answers

Which component's output is electrically insulated from the input and three-phase output?

<p>Battery Charger (B)</p> Signup and view all the answers

Which of the following is true regarding the converters' output?

<p>BUR3 has a fixed frequency output at 50 Hz. (B)</p> Signup and view all the answers

What is the rated supply voltage for the traction rolling stock?

<p>1000 V AC +200 V (C)</p> Signup and view all the answers

What is the rated insulation voltage for the intermediate circuit?

<p>900 V (B)</p> Signup and view all the answers

What is the apparent power rating of the traction rolling stock?

<p>100 KVA (A)</p> Signup and view all the answers

What is the rated frequency for the traction rolling stock?

<p>50 Hz (B)</p> Signup and view all the answers

What is the maximum battery charger current when both the user and battery are connected?

<p>110 A (B)</p> Signup and view all the answers

The rated voltage (fundamental r.m.s) for the AC output is?

<p>415 V (D)</p> Signup and view all the answers

What is the short-term overload current for the intermediate circuit?

<p>190 ADC (A)</p> Signup and view all the answers

What is the rated current for the AC output, which includes the battery charger?

<p>140 A (C)</p> Signup and view all the answers

What test voltage is used for the rated insulation voltage?

<p>4250 V (C)</p> Signup and view all the answers

What is the primary function of the intermediate circuit reactor in a DC link filter?

<p>To smooth the pulsating energy flow from the input rectifier (C)</p> Signup and view all the answers

What does the intermediate circuit capacitor (CZ) primarily provide to the system?

<p>A low impedance voltage source essential for inverter functioning (D)</p> Signup and view all the answers

How many parallel-connected electrolytic capacitors are in the intermediate circuit capacitor?

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

What is the purpose of the resistors connected to the series stage of the capacitor?

<p>To balance the voltage across the series connected stage (C)</p> Signup and view all the answers

What do the coils in the choke of the intermediate circuit reactor primarily keep away from the inverter?

<p>Voltage spikes (D)</p> Signup and view all the answers

Which components comprise the three-phase inverter?

<p>Three single-phase inverter modules (C)</p> Signup and view all the answers

What characteristic of the switching sequences of the three modules is stated?

<p>They are generally steady state conditions (B)</p> Signup and view all the answers

What role do discharge resistors play in the circuit?

<p>They discharge the voltage from capacitors safely (D)</p> Signup and view all the answers

Which of the following describes the role of the capacitor in the intermediate circuit?

<p>It absorbs fluctuating current components while maintaining voltage stability (A)</p> Signup and view all the answers

In what way does the intermediate circuit reactor affect current?

<p>By smoothing out pulsating energy flow (A)</p> Signup and view all the answers

What is the rated insulation voltage for Box 2?

<p>150 V (D)</p> Signup and view all the answers

What is the power consumption of the control unit?

<p>120 W (D)</p> Signup and view all the answers

Which component is NOT listed as part of the main parts of the converter?

<p>Three phase transformer (A)</p> Signup and view all the answers

What is the maximum thermal loss for Box 1 at rated power?

<p>2 KW (C)</p> Signup and view all the answers

What is the typical output DC voltage maintained by the rectifier?

<p>$550 V$ (C)</p> Signup and view all the answers

What is the range of the ventilator supply voltage?

<p>36..56 V (C)</p> Signup and view all the answers

Which factor is NOT considered when calculating the average value of the rectifier output voltage?

<p>Output DC voltage (A)</p> Signup and view all the answers

What is the power loss of the ventilator?

<p>$5 W$ (B)</p> Signup and view all the answers

What is the air rate provided by the cooling system?

<p>5 m/sec (B)</p> Signup and view all the answers

What is the test voltage referenced for Box 1 during testing?

<p>2600 V (D)</p> Signup and view all the answers

What does the variable $n$ represent in the equation for the rectangular output voltage of the inverter?

<p>The harmonic order (C)</p> Signup and view all the answers

Which of the following statements about the relationship between the output voltage and the shaft power of the motor is true?

<p>Shaft power can be expressed as a function of the fundamental component. (A)</p> Signup and view all the answers

How does the inductor affect the harmonics in the three-phase system?

<p>It slightly attenuates the harmonics. (C)</p> Signup and view all the answers

In what scenario are the frequency and amplitude of the output voltage set away from the reference value?

<p>Under dynamic conditions using PWM. (B)</p> Signup and view all the answers

What is the primary function of the diode bridge in the battery charger circuit?

<p>To rectify the AC voltage from the inverter. (B)</p> Signup and view all the answers

What features are included in the auxiliary converter system's cooling mechanism?

<p>External forced convection with thermostats (B)</p> Signup and view all the answers

Under what condition will the battery charger receive supply from converter BUR2?

<p>When BUR2 has a fault (D)</p> Signup and view all the answers

Which output characteristic is unique to converter BUR3 compared to BUR1 and BUR2?

<p>Rated frequency output at 50 Hz (C)</p> Signup and view all the answers

What is the primary purpose of the battery charger in the auxiliary converter system?

<p>To charge locomotive batteries and supply low voltage loads (C)</p> Signup and view all the answers

How is the output of the converters electrically configured in relation to other components?

<p>It is isolated from both input and three-phase output (B)</p> Signup and view all the answers

What is the total output capacity rating of each auxiliary converter?

<p>100 KVA (C)</p> Signup and view all the answers

Which factor dictates the operation of the fans within the converter boxes?

<p>Internal temperature exceeding 50°C (D)</p> Signup and view all the answers

What is the average value of the rectifier output voltage maintained by the half controlled asymmetrical type GTO rectifier?

<p>550 V (A)</p> Signup and view all the answers

What is the test voltage for the rated insulation voltage of the intermediate circuit?

<p>2600 V (A)</p> Signup and view all the answers

What is the supply voltage range for the control unit?

<p>77..137.5 V (C)</p> Signup and view all the answers

At what voltage is the test voltage for Box 2 during testing conducted?

<p>1500 V (C)</p> Signup and view all the answers

What is the rated insulation voltage of the traction rolling stock?

<p>1200 V (B)</p> Signup and view all the answers

What is the maximum battery charger current when only the battery is connected?

<p>80 A (D)</p> Signup and view all the answers

What are the thermal losses at rated power for Box 2?

<p>5 KW (A)</p> Signup and view all the answers

What is the ventilator supply voltage for cooling by forced air?

<p>36..56 V (D)</p> Signup and view all the answers

What is the rated current (r.m.s) specified for the traction rolling stock?

<p>150 A (B)</p> Signup and view all the answers

At what voltage does the intermediate circuit operate?

<p>550 VDC (D)</p> Signup and view all the answers

Which component is part of the main parts of the converter?

<p>Half controlled rectifier bridge (B)</p> Signup and view all the answers

What is the frequency range mentioned for the traction rolling stock?

<p>50 Hz + 3% (D)</p> Signup and view all the answers

What does the average value of the rectifier output voltage formula depend on?

<p>Input RMS voltage and phase angle (A)</p> Signup and view all the answers

Which of the following represents the rated AC output current that includes the battery charger?

<p>140 A (A)</p> Signup and view all the answers

What is the short-term overload current specified for the intermediate circuit?

<p>190 ADC (C)</p> Signup and view all the answers

What is the air rate maintained by the cooling system?

<p>5 m/sec (B)</p> Signup and view all the answers

What is the rated frequency for the AC outputs from BUR3?

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

Which device is responsible for converting AC to DC in the system?

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

What function does the intermediate circuit reactor primarily serve in a DC link filter?

<p>It smooths the pulsating energy flow and prevents voltage spikes. (A)</p> Signup and view all the answers

What characteristic does the intermediate circuit capacitor (CZ) provide to the system?

<p>It acts as a current source for inductive loads. (B)</p> Signup and view all the answers

In the structure of the intermediate circuit capacitor, what is the purpose of the resistors connected to the series stage?

<p>To equalize the current distribution among capacitors. (C)</p> Signup and view all the answers

How is the three-phase AC voltage generated by the inverter?

<p>By switching the single-phase inverter modules ON and OFF. (D)</p> Signup and view all the answers

What are the coils in the choke of the intermediate circuit reactor designed to protect against?

<p>Voltage spikes affecting the connected load. (D)</p> Signup and view all the answers

Which of the following describes the configuration of the intermediate circuit capacitor?

<p>A series circuit of electrolyte capacitors connected in parallel. (C)</p> Signup and view all the answers

What factor significantly influences the dimensions of the resistors in the intermediate circuit capacitor’s series stage?

<p>The leakage current from the capacitors. (A)</p> Signup and view all the answers

What aspect of the switching sequences of the three-phase inverter is highlighted?

<p>They function optimally under steady state conditions. (D)</p> Signup and view all the answers

What primary benefit does the three-phase inverter provide in converting DC to AC?

<p>It allows for precise control of motor performance. (C)</p> Signup and view all the answers

Flashcards

Auxiliary Converter System

A static system in locomotives, composed of multiple converters (BUR1, BUR2, BUR3) and a battery charger. It's designed for providing power for auxiliary train systems, like the locomotive battery charger.

BUR1 Converter

One of three auxiliary converters in the system, offering variable frequency output from 0 to 50 Hz.

BUR2 Converter

One of three auxiliary converters that can send power to the battery charger in case of BUR1 failure; it has variable frequency output from 0-50 Hz

BUR3 Converter

Converter in the auxiliary system providing fixed 50 Hz output and powering the battery charger

Signup and view all the flashcards

Battery Charger

Charged by BUR3 or BUR2 when needed and supplies low voltage power, electrically isolated from other parts.

Signup and view all the flashcards

Converter Output Rating

Each converter (BUR1, BUR2, BUR3) has 100 KVA output and can output 415 V for three-phase electrical systems.

Signup and view all the flashcards

Cooling System

Auxiliary converters have forced cooling at 5 m/sec and thermostats for automatic fan startups to maintain temperature below 50°C.

Signup and view all the flashcards

Input Supply Voltage

The AC voltage provided to the system, ranging from 1000 V AC -200 V to +300 V.

Signup and view all the flashcards

Apparent Power

The 100 KVA apparent power is the product of voltage and current.

Signup and view all the flashcards

Intermediate Circuit Voltage

The voltage in the intermediate circuit is 550 VDC.

Signup and view all the flashcards

Rated Intermediate Circuit Current

The max current in the intermediate circuit is 155 ADC.

Signup and view all the flashcards

Short Term Overload Current (Intermediate)

The system can handle 190 ADC for a short time.

Signup and view all the flashcards

Rated AC Output Voltage

The fundamental AC output voltage is 415 V, this is the RMS value.

Signup and view all the flashcards

Rated AC Output Frequency

The fundamental output AC frequency is 50 Hz.

Signup and view all the flashcards

Rated AC Output Current

The combined AC output current (including battery charger) is 140 A.

Signup and view all the flashcards

Intermediate Circuit Insulation Voltage

The Intermediate circuit insulation voltage is 900 V (for capacitor).

Signup and view all the flashcards

Rectifier input voltage

AC voltage fed into the rectifier, to be converted to DC.

Signup and view all the flashcards

Half-controlled asymmetrical GTO rectifier

A type of rectifier that converts AC to DC using Gate Turn-Off Thyristors (GTOs).

Signup and view all the flashcards

Rectifier output voltage

The DC voltage produced by the rectifier, approximately 550 V.

Signup and view all the flashcards

Intermediate filter

A filter consisting of an inductor and capacitor, smoothing the DC voltage.

Signup and view all the flashcards

Converter active power

The power transmitted through the converter, calculated as UZ x IZ.

Signup and view all the flashcards

Three-phase inverter

A circuit that converts DC power to AC power in the output stage of a traction system.

Signup and view all the flashcards

Control unit voltage range

The operating voltage range for the control unit, 77-137.5 V.

Signup and view all the flashcards

Control Unit Power Consumption

The power consumed by the control unit, 120 W.

Signup and view all the flashcards

Thermal losses box 1

2 kW heat loss in the first box.

Signup and view all the flashcards

Thermal losses box 2

5 kW heat loss in the second box.

Signup and view all the flashcards

Inverter Output Voltage

The output voltage of an inverter, represented as an infinite sum of sine waves with varying frequencies, is crucial for driving the electric motor in traction applications.

Signup and view all the flashcards

Fundamental Frequency (f1)

The base frequency of the inverter's output voltage, typically the desired operating frequency for the motor and other equipment.

Signup and view all the flashcards

Harmonic Frequencies

Additional frequencies present in the inverter's output voltage, which are multiples of the fundamental frequency. These harmonics can be undesirable in some applications, such as creating noise and heating.

Signup and view all the flashcards

RMS Voltage of Fundamental (U1rms)

The effective or root-mean-square value of the fundamental component of the inverter's output voltage. Used for calculations related to power and efficiency.

Signup and view all the flashcards

Load Type Impact

The type of load connected to the inverter influences how harmonics are handled. Resistive loads respond to all frequencies, while inductive loads react differently.

Signup and view all the flashcards

DC Link Filter

A circuit in traction rolling stock that smoothes the pulsating energy flow from the rectifier and supplies DC current with ripple. It consists of an intermediate circuit reactor and capacitor.

Signup and view all the flashcards

Intermediate Circuit Reactor

A component of the DC link filter that helps smooth out the pulsating DC current and provides a DC current with superimposed ripple.

Signup and view all the flashcards

Intermediate Circuit Capacitor

A component of the DC link filter that absorbs the current fluctuations and provides a stable DC voltage. It also supplies magnetization current to the inductive load.

Signup and view all the flashcards

Inverter Modules

Individual components of the three-phase inverter that generate individual single-phase voltages and are switched on and off according to a specific sequence to create a three-phase AC voltage.

Signup and view all the flashcards

Switching Sequences

The predetermined pattern in which the inverter modules are switched on and off to generate the desired three-phase AC voltage.

Signup and view all the flashcards

Steady State Conditions

The stable operating state of the three-phase inverter where the output AC voltage remains constant.

Signup and view all the flashcards

Inductive Load

An electrical load that stores energy in a magnetic field due to its inductance.

Signup and view all the flashcards

Voltage Waveforms

Visual representation of the voltage changes over time across different points in the circuit, particularly across the input and output of the DC link filter.

Signup and view all the flashcards

Half-controlled rectifier

A type of rectifier that uses GTOs to convert AC to DC and controls the output DC voltage using a firing angle.

Signup and view all the flashcards

Thermal losses

Heat generated by the system components, such as the boxes and ventilator.

Signup and view all the flashcards

Ventilator power losses

Energy consumed by the ventilator to cool the system, typically around 5 watts.

Signup and view all the flashcards

Active power transmitted

The actual power transferred through the converter, calculated as the product of output voltage and current.

Signup and view all the flashcards

GTO rectifier

A type of rectifier that uses Gate Turn-Off Thyristors (GTOs) for switching, allowing for faster and more precise control.

Signup and view all the flashcards

Output inductor

A component that smooths the AC current output of the inverter, reducing ripple and harmonics.

Signup and view all the flashcards

Supply Voltage Range

The AC voltage input for the traction system, fluctuating between 1000 V AC -200 V and 1000 V AC +300 V. This range ensures the system operates within an acceptable voltage tolerance.

Signup and view all the flashcards

Intermediate Circuit Current

The maximum current that flows within the intermediate circuit, which is 155 ADC under normal operation. This value is important for system performance.

Signup and view all the flashcards

Short-Term Overload Current

The maximum current the intermediate circuit can handle for a short period, exceeding the rated current at 190 ADC. This provides flexibility for occasional power surges.

Signup and view all the flashcards

Output AC Voltage

The AC voltage provided by the auxiliary converter, with a fundamental RMS value of 415 V. This is the usable voltage for powering auxiliary systems.

Signup and view all the flashcards

Output AC Frequency

The AC frequency output by the auxiliary converters, typically 50 Hz, ensuring compatibility with the electrical systems in the train.

Signup and view all the flashcards

Output AC Current

The maximum combined current output from the auxiliary converters, reaching 140 A, including the current used for the battery charger.

Signup and view all the flashcards

Battery Charger Current

The current used for charging the locomotive battery. It can range from 80 A (only for battery charging) to 110 A (with additional loads).

Signup and view all the flashcards

Why is the intermediate circuit capacitor important?

It provides a stable DC voltage, absorbs current fluctuations, and supplies magnetization current for the inductive load.

Signup and view all the flashcards

Study Notes

Auxiliary Converter

  • Each locomotive has two boxes housing the auxiliary converter system.
  • Box 1 contains BUR1
  • Box 2 contains BUR2, BUR3, and a battery charger.
  • The battery charger can be powered by either of the two converters.
  • Figure 6.1 details the converter's role within the locomotive.
  • Figure 6.2 illustrates the essential components of the auxiliary converter and battery charger.

Converter Design

  • Three auxiliary converters are linked to the main transformer's auxiliary services winding.
  • Each converter has a 100 kVA output rating.
  • The converters have short-circuit-proof three-phase outputs at 415 V.
  • BUR1 and BUR2 converters have variable outputs ranging from 0 to 50 Hz
  • BUR3 has a fixed output frequency of 50 Hz
  • The battery charger is supplied by BUR3.
  • If BUR3 fails, BUR2 takes over battery charging duties.

Battery Charger

  • The battery charger outputs approximately 111 V.
  • It charges the locomotive batteries.
  • Supplying low-voltage loads.
  • The low-voltage output is electrically isolated from both the input and three-phase output.

Cooling System

  • The converters use external forced-convection cooling (approximately 5 m/sec).
  • Thermostats monitor internal temperatures.
  • If the temperature exceeds 50°C, cooling fans activate to reduce temperature to below 35°C.

Component Placement

  • Converter boxes and three-phase output chokes are placed in the locomotive's machine room.
  • Intermediate chokes are integrated into the main transformer tank to conserve space and reduce weight.

Technical Data

  • Input:
  • Supply voltage: 1000 V AC ± 200 V to −300 V
  • Apparent power: 100 kVA
  • Current (RMS): 150 A (for 100 kVA and 700 V)
  • Frequency: 50 Hz ± 3%
  • Rated insulation voltage: 1200 V
  • Test voltage (50 Hz/60 sec): 4250 V
  • Intermediate circuit:
  • Voltage: 550 VDC
  • Rated current: 155 ADC
  • Short-term overload: 190 ADC
  • Rated insulation voltage: 900 V (capacitor)
  • Test voltage (50 Hz/60 sec): 2600 V

Output Specifications

  • AC:
  • Rated voltage (RMS): 415 V
  • Rated Frequency (BUR1 & 2): 50 Hz
  • Rated Frequency (BUR3): 50 Hz
  • DC:
  • Rated Voltage: 111 V
  • Other Outputs:
  • Rated current (AC, inc. battery charger): 140 A
  • Max. battery charger current (only battery): 80 A
  • Max. battery charger current (user + battery): 110 A
  • Control Unit:
  • Supply voltage: 77-137.5 V (operating range)
  • Power consumption: 120 W

Thermal Losses

  • Box 1: 2 kW
  • Box 2: 5 kW
  • Ventilator supply voltage: 36-56 V
  • Ventilator power losses: 5 W
  • Air rate: 5 m/sec

Circuit Descriptions

  • The diagram depicts the converter main elements: half-controlled rectifier bridge, intermediate filter (inductor and capacitor), three-phase inverter, and other components.

  • Rectifier circuits convert AC to DC.

  • Output voltage/current waveforms in these modules are shown in Figures 6.3-6.6.

  • These configurations can be helpful in regulating and protecting the process.

  • The rectifier uses asymmetrical GTOs with approximately a 550V DC output.

  • The DC link filter smooths the pulsating DC current using a reactor and capacitor.

  • The three-phase inverter generates a three-phase AC voltage from the DC link voltage.

  • Protective devices, such as the battery charger circuit breaker (100), surge arresters, and the damping filter RC, are crucial for safety and performance.

  • Measurement devices, such as voltage measuring transformers and transducers, aid in monitoring the system's health.

  • The auxiliary converter control unit handles control and protection functions using a bus interface.

  • Protective devises like the circuit breaker protect against overload.

  • Input fuses and surge arresters protect against short circuits and overvoltage.

  • A damping filter is used to prevent spurious thyristor firing.

  • Measurement equipment, such as voltage transducers, provide data for system monitoring.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Auxiliary Converter Technical Data PDF

Description

Explore the essential components and design of auxiliary converters used in locomotives. This quiz covers the roles of various converters, their output specifications, and the integration of battery chargers. Understand how these systems work together to maintain locomotive operations.

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser