Project Report on Electronics-TIMS

INDUSTRIAL TRAINING REPORT ON DELHI METRO RAIL CORPORATION LTD.

MAJOR TRAINING DURATION: 6 WEEKS DEPARTMENT: ROLLING STOCK VENUE: SHASTRI PARK DEPOT, NEW DELHI

PREPARED BY:  TAPAN DESHWAL JAYPEE INSTITUTE OF ENGINEERING AND TECHNOLOGY (ELECTRONICS AND COMMUNICATION ENGINEERING)  PARUL GOEL INDIRA GANDHI INSTITUTE OF TECHNOLOGY (ELECTRONICS AND COMMUNICATION ENGINEERING)  MANISHA ARORA KURUKSHETRA UNIVERSITY (INSTRUMENTATION ENGINEERING)

ACKNOWLEDGEMENT

It is indeed a great pleasure for me to present this Summer Training Report on DMRC (Delhi Metro Rail Corporation) as a part of the curriculum of the B.Tech. course electronics and communication engineering I take this golden opportunity to thank all my mentors at DMRC who with their unstinted support and venerated guidance made this training a real success. I express my sincere thanks to Mr.Rajbir Yadav ASST-MANAGER/RS and Mr. Chandan Kumar Sales-Manager ROTEM. I pay my special thanks to Mr. Sameer Lowe JE/RS/ELECTRONICS , Mr. Brajesh Kumar Dwivedi JE/RS/ELECTRONICS who in spite of their busy schedule have lent their precious time for helping out me to understand various system used in DMRC. I will be failing in my duty if I am not mentioning the technical demonstrations as given by the reverent staff of DMRC. There is no denying the fact that DMRC is the epitome of modern technology and getting training at such an organization is an exquisite learning experience that made a mark at the profoundest part of my mind.

DMRC (Delhi Metro Rail Corporation) Introduction

is like a dream come true for Delhi, a revolutionary change in the city transport. Delhi needs metro system in the first place and it would change things for the better not only for people who would be using it and but for the people living in Delhi by reducing congestion, air pollution, noise pollution and accidents. METRO

Formation of DMRC A company under the name DMRC was registered on 30.05.1995 under the companies act for construction and operation of the metro project. DMRC is the joint venture of the Government of India and Government of National Capital Territory of Delhi. It started functioning in November 1997. It appointed General consultant in August, 1998 to assist them for implementation of the project. This is the consortium office international consultancy company led by Pac Consultants International (PCI), Japan. The whole project of approximately 200Kms is to be completed in three phases up to 2021, the first phase of the project, comprising of approximately 62.06Kms, is currently operational. It is having 18 stations in Line 1 (Red Line), 10 stations in Line 2 (Yellow Line) and 22 stations in Line 3 (Blue Line). Benefits of Delhi Metro on completion On the completion of the first phase of the Delhi Metro, it would be catering to around 2.18 million commuters per day resulting in decongestion of the roads. This would also mean that there would be less number of buses on the roads. It has also reduced the travel time. Also the pollution level is reduced to about 50%. Since the first phase of the Delhi Metro is operational a large number of commuters are having a lot of convenience in reaching their desired destination in the required time.

Advantages of Rail-based Transit System

•

Can achieve carrying capacity as high as 60000-80000.

•

Required 1/5th energy per passenger compared to Road-based system.

•

Causes no air pollution in the city.

•

Causes lesser noise level.

•

Occupies no road space if underground and only about of 2 meter width of the road if elevated.

•

Carries same amount of bus traffic or 33 lanes of private motor car.

•

Is more reliable, comfortable and safer than road system.

•

Reduces journey time (about 50% to 75% )

Awards won The Delhi Metro has been awarded OHSAS (Occupational Health and Safety Assessment Sequence 18001) by RINA (Registro Italiano Navale India Pvt. Ltd.), Geneva. To help in proper maintenance the DMRC has been divided into departments and sub departments:     

Signaling Telecom Rolling Stock P. Way AFC

& many other sub departments

OUTLINE The Delhi rail corridor system is a heavy rail mass transit system covering a route length of approx 44km, providing commuter services for the Delhi population. The traction power supply consists of a flexible catenary fed at 25000v, 50 Hz single phase.

TRAIN CONFIGURATION The basic train consist is made of 4 cars which comprise of 2 motor cars (M) and 2 driving trailer cars (DT). Automatic Coupling

Semi Automatic Coupling

Driving Trailer Coach

Automatic Coupling

Motor Coach

The formation of the 4 car train is DT  M  M  DT

DT

-

M

-

M

-

DT

Each DTM car pair is connected together by a semi-permanent coupler .this means that for service operation the train consist is fixed and cannot be separated. However, for maintenance purposes, maintenance staff can physically disengage the semi-permanent couplers so that maintenance activities can be conducted on individual cars. Between each car pair, an automatic coupler is used. This allows quick and easy coupling and decoupling of the paired cars.

Other possible train formations are – •

6 car train

DT

•

-

M

-

T

-

M

-

M

-

DT

8 car train

DT

-

M

-

T

-

M

-

Here T car is the non-driving trailer car.

MAJOR SYSTEMS •

C/I Propulsion System

•

Auxiliary Power Supply System

•

Train Integrated Management System

•

PA-PIS System

T

-

M

-

M

-

DT

C/I PROPULSION SYSTEM The Converter/Inverter Propulsion System provides the tractive effort that accelerates the train and braking effort to decelerate the train. The C/I Propulsion System takes power from the catenary line at 25000V and transforms this to 1058 V using the main transformer. The ac supply is then rectified into a dc supply, which is converted into a Variable Voltage Variable Frequency (VVVF) 3 phase supply for powering of the traction motors. Its advantages over Camshaft controllers or Chopper controllers are:  Energy Saving  Regenerative braking  Induction motor control for efficient transfer of tractive torque to the rail  Insulated Gate Bipolar Transistors (IGBT) are used as main switching elements  Reduced weight and size  No commutator or brush gear in induction motor. Therefore its power-to-weight ratio is high.  To change from powering to braking or from forward to reverse direction, only the inverter output frequency or phase rotation is changed. No additional circuits or components are required.  Maintenance The induction motor does not have a commutator. Therefore, high maintenance items are eliminated. The C/I Propulsion System consist of the following main components: • • • • • •

Vacuum Circuit Breaker AC Arrestor Emergency Ground Switch Main Transformer C/I Box Traction Motor

INTERFACE DIAGRAM

Pantograph 25,000 V AC

Emergency Ground Switch

Traction Supply 25,000 V AC

Vacuum Circuit Breaker

C/I Box

AC Arrestor

Main Transformer Traction Motor

Traction Motor

Traction Motor

Traction Motor

Main Transformer Supply 1058 V AC

C/I Box Output 0-1450 V 0-137 Hz

 25,000 V AC SINGLE PHASE The train is connected to the 25000 V catenary lines by the pantograph mounted on each trailer car (driving and non driving). When the pantograph is raised the 25 KV line is

connected to the Vacuum Circuit Breaker. The voltage level can vary between 17,500 and 30,000 V.



VACUUM CIRCUIT BREAKER This is a single pole, bi-directional high speed AC circuit breaker. Its function is to isolate (open contacts) or connect (close contacts) the 25KV line to the train mounted equipment. Being a circuit breaker, the VCB also isolates the train mounted equipment when a over current condition occurs due to a fault on the train or on the 25KV line.



AC ARRESTOR It is a device that protects the train mounted equipment from excessive high voltage transient conditions, caused by lightning strikes on the 25KV line. When a transient condition occurs, the AC arrestor quickly becomes a low resistance path to earth and the energy of the transient spike is absorbed. Once the spike is absorbed the AC arrestor becomes a high resistance path to ground.



EMERGENCY GROUND SWITCH It is a manually operated high voltage switch that is used to connect both sides of the VCB to earth. Maintenance staff usually operates this switch when working on the train. By earthing both sides of the VCB maintenance staff are protected against accidental energizing of the 25KV line or propulsion system.



MAIN TRANSFORMER Its function is to reduce the 25KV line to approximately 1KV (2 off secondary windings). It consists of one primary winding which is connected to the 25KV line. Two secondary windings are connected to the C/I box. A secondary winding output provides the power supply for a bogie. One tertiary winding output provides power to the Auxiliary Power Supply System.

 1058 V SINGLE PHASE This is the output voltage level of the main transformer secondary winding, when the nominal primary input voltage is 25,000 volts. 

C/I BOX

This converts the 1058 V single phase supply in to a Variable Voltage Variable Frequency 3 phase supply. This is generally called a VVVF drive. The output of the C/I box is controlled so that its output voltage varies from 0V to 1450V, and the frequency varies from 0 to 137 Hz. By adjusting this voltage and frequency, the power to the traction motors is controlled to give the required torque and speed according to the drivers demand signal.  0 – 1450 V , 0 – 137 Hz 

TRACTION MOTOR The C/I box has two independent output circuits, one for each set of traction motors mounted in a bogie. The C/I output voltage varies from 0V to 1450V, and the frequency varies from 0 to 137 Hz. The output of the C/I box is connected to the traction motors. The traction motors are mounted onto the bogie frame and provide the necessary torque to move the train. By having two independent output circuits, the control of each set of traction motors is also independent. This allows failed bogie circuits to be isolated without affecting the good bogie circuit.

AUXILIARY POWER SUPPLY SYSTEM

This system provides the 415 V AC supply to operate the auxiliary loads on the train. The Auxiliary Power Supply System uses a 3 phase independent and instantaneous voltage waveform control system that has the advantages of:   

Low output voltage distortion Low voltage fluctuation against load & input voltage transient charging Low audible noise

IGBT are used as the main power switching device. These are cooled by natural convection using a heat pipe, with the coolant being pure water. The 415 V output supply is galvanically isolated from the 25KV line by the main transformer. The Auxiliary Power Supply System consists of the following main components: • • • • •

Vacuum Circuit Breaker AC Arrestor Emergency Ground Switch Main Transformer SIV Box

INTERFACE DIAGRAM Pantograph 25,000 V AC

Emergency Ground Switch

Vacuum Circuit Breaker

AC Arrestor

Main Transformer

Traction Supply 25,000 V AC

Main Transformer Supply 470 V AC

Battery Charger

SIV Box

Main Air Compressor

Passenger Air Conditioner SIV Box Output 415 V AC,50 Hz

Main Transformer Oil Pump & Blower Motors

SIV Box Output 230 V AC

AC Passenger Lighting

Battery SIV Box Output 110 V DC

Driver Air Conditioner

Socket Outlet

Control Circuit

DC Passenger Lighting

 25,000 V AC SINGLE PHASE The train is connected to the 25000 V catenary lines by the pantograph mounted on each trailer car (driving and non driving). When the pantograph is raised the 25 KV line is connected to the Vacuum Circuit Breaker. The voltage level can vary between 17,500 and 30,000 V. 

VACUUM CIRCUIT BREAKER

This is a single pole, bi-directional high speed AC circuit breaker. Its function is to isolate (open contacts) or connect (close contacts) the 25KV line to the train mounted equipment. Being a circuit breaker, the VCB also isolates the train mounted equipment when a over current condition occurs due to a fault on the train or on the 25KV line.



AC ARRESTOR It is a device that protects the train mounted equipment from excessive high voltage transient conditions, caused by lightning strikes on the 25KV line. When a transient condition occurs, the AC arrestor quickly becomes a low resistance path to earth and the energy of the transient spike is absorbed. Once the spike is absorbed the AC arrestor becomes a high resistance path to ground.



EMERGENCY GROUND SWITCH It is a manually operated high voltage switch that is used to connect both sides of the VCB to earth. Maintenance staff usually operates this switch when working on the train. By earthing both sides of the VCB maintenance staff are protected against accidental energizing of the 25KV line or propulsion system.



MAIN TRANSFORMER Its function is to reduce the 25KV line to approximately 1KV (2 off secondary windings). It consists of one primary winding which is connected to the 25KV line. Two secondary windings are connected to the C/I box. A secondary winding output provides the power supply for a bogie. One tertiary winding output provides power to the Auxiliary Power Supply System.

 470 V AC SINGLE PHASE 

SIV BOX

This is the output voltage level of the main transformer tertiary winding, when the nominal primary input voltage is 25,000 volts. The SIV box converts the 470 V single phase supply into a 415 volt, 3 phase 50 Hz supply for the train auxiliary loads. The output of the SIV box is controlled so that the 415 V voltage and 50 Hz frequency is constant even if the input voltage or frequency changes.

 415 V AC,50 Hz This is the main power supply for train auxiliary loads. These auxiliary loads being:     

Passenger Air Conditioners Driver Cab Air Conditioners Main Air Compressor Main Transformer Oil Pump Blower motors

 230 V AC,50 Hz This provides power to the following:  

AC Passenger Lighting Socket Supply

The 230 AC supply is generated using a step down transformer (415V to 230V) within the SIV box.  110 V DC This provides power to the following:   

Car Batteries Train Control Circuit DC Passenger Lighting

This DC supply is generated by a battery charger unit mounted within the SIV box. The battery charger consists of a step down transformer (415V to 104V) and control rectifier. The DC voltage is normally maintained at 110V.The battery charger output current is also controlled limited, therefore, under conditions of overload charging current the output voltage can be less than 110V.Such an overload condition could be charging of a dead battery.

TRAIN INTEGRATED MANAGEMENT SYSTEM The Train Integrated Management System consists of the following major equipment items; •

Central Unit

•

Local Unit

•

Display Unit

•

Display Controller

A train is considered as a very harsh and hostile environment for data communication networks. The Train Integrated Management System (TIMS) operates to perform integrated monitoring and control of train equipment. A source of electrical noise on trains includes heavy energy conversion such as CI and SIV. It is important therefore to carefully select a suitable network carrier to ensure overall system reliability and system safety. The requirement is that the communication must be noise-resistant, deterministic, fast and flexible. The most suitable LAN for this application is ARCNET. The Train Integrated Management System interfaces with the following systems located throughout the train; these systems are: •

Propulsion System (CI)

•

Auxiliary Power Supply (SIV)

•

Brake system (BECU)

•

Door Control System (DCU)

•

Air conditioners

•

AVAS & PA

•

ATC System

•

TR

The Train Integrated Management System also monitors Train Line status, switch and circuit breaker positions. The Train Integrated Management System has control over various functions throughout the Train. This monitoring and control is carried out via the parallel input / output interface.

Equipment Locations Table 1B-11-01-00-1

TIMS Equipment Locations

Car Type Equipment

DT

Central Unit

X

Local Unit

M X

Display Unit

X

Display Controller

X

Equipment function The Train Integrated Management System provides a centralized function to control and monitor the train borne systems and devices. It also displays relevant information to the Driver.

Networking Protocol TIMS uses the following protocols: (a) Train BUS (LAN) • Shielded twisted pair •

Duplicate bus by Bi-directional "Ring"

•

Dipulse signal 2.5Mbps (ANSI 878.1 ARCNET)

• Each node has a bus "Bypass switch" for a node fault. (b) Car BUS (LAN) (TIMS - Equipment Communication) • 3 wires/channel (shielded pair with third conductor) •

Multi-drop connection (appropriate grouping)

•

RS485, NRZI code HDLC (ISO3309/4335)

• 9.6k/38.4kbps (c) Vehicle Bus (LAN) (Node to Node Communication) Shielded Twisted pair • 3 wires/channel (shielded pair with third conductor)

Operating System Interface (OSI) Layers Model

USER Level OSI

Train Bus

Car Bus

Application of CU/ LU

Application of CU/ LU

7

Application Interface

6

Presentation

5

Session

Train BUS Comms.

Car BUS Comms.

4

Transport

Handler

Handler

3

Network

(Standard package)

(Standard package)

2

Link Layer Interface

ARCNET (HDLC like)

HDLC subset

1

Physical

Dipulse signal (ANSI 878.1 ARCNET) RS485 3 wires

Transmission method

Screen Twisted pair

Screen Twisted pair with signal ground.

Real Time Protocol And Interface TIMS employs a real time operating system RTM-68K and networking protocols base on the ARCNET and HDLC. The deterministic medium access control method is used as follows: (a) ARCNET: Token passing (b) HDLC: Polling/selecting method (Normal response mode of HDLC)

The two networks are used and work together. One is based on ARCNET and the other is based on HDLC.

The following checking mechanisms are used to ensure the validity of transmitted data. •

CRC

: 16-bit CRC.

•

Length

: Data length check.

•

Sequence number: Sequence number check for numbered information.

•

Redundant code (for special command if necessary): 2-byte code command.

•

Communication Check (for special command if necessary): 16-bit code oscillating between 05555H and 0AAAAH in every 200 ms for detection of no up-date fault.

If TIMS detects a data error or a no up-date fault, TIMS switches the output to safe state (normally “off” state) by software logi

Network traffic (c) Transmission Delay time (Worst) (i) Delay Time = ((No. of bytes x 1.7µs x 2) + (145.4 + (4.4 x No. of bytes)) x10 -3 + 28 µs) x N where N is the number of nodes data passes through.

(d)

(e)

(f)

(g)

(ii) Delay time for a 6 node (4 car train) transmitting 248 bytes of data. (iii) = ((248 x 1.7µs x 2) + (145.4 + (4.4 x 248)) x10-3 + 28 µs) x 5 = 10.54 ms Normal Token Ring Scan Time (i) The Melco Token Passing Architecture passes the token every 10 milliseconds. (ii) The Maximum Normal Token Ring Scan Time for a 6 node (4 car train) can be calculated with following formula: (N x 10) + α where N is the Number of Nodes. (iii) = (6x 10) ≅ 60 ms + α where α is the tolerance, specified by Melco. (Designed to be very small) Worst Token Ring Scan Time (iv) Worst Scan Time = Scan Time of a “Normal Token Passing” + “Abnormal Token Passing period β” (v) Worst Scan Time for a 6 node (4 car train) with a cable breakage: Delay Time = ((3 x 1.7µs x 2) + (145.4 + (4.4 x 3)) x10 -3 + 28 µs) x 5 = 0.793191 ms = β Worst Token Ring Scan Time = (60 ms + α) + 0.793191 ms = 60.793191 ms + α Thus we estimate the Worst Token Ring Scan time with α ≅ 100 ms. Local Bus Scan Time (Worst) (vi) Scan Time (ms) = Polling Cycles of the Subsystem connected to the same Local Unit. Total System Worst Scan Time (vii) Total System Worst Scan Time = (Worst Token Ring Scan time) + (Worst Local Bus Scan Time of equipment) + (Worst Transmission Data Delay time to CU) + (Worst Scan Time between CU and VDU ).

ARCNET (ANSI 878.1) for Train LAN ARCNET adopts the ANSI 878.1, 2.5 Mbps (Megabits per second), 16 Vpp Dipulse Signaling method. It has a high signal to noise ratio (approx. 11.5dB). It passes the IEC 801-4 (Fast High Voltage Electrical Transient test) and as a result, the network has better errorresistive performance in electrically hostile environment, which in turn gives lower bit rate error Specification of ARCNET ARCNET Signal Type

Base Band

Transmission Speed

2.5Mbps

Transmission Signal Level

16Vpp

Receiving Signal Threshold

3 Vpp

Medium Access Control

Token Passing (Ring)

ARCNET adopts the Token-passing Protocol, which provides predictable response times. Each network event occurs within a predetermined time interval. The interval period is based on the number of nodes on the network. A significant advantage of ARCNET is its ability to adapt to changes on the network. Whenever a new node is activated or deactivated, a network reconfiguration is performed. When fault occurs in one of the TIMS processing units, the network can adjust itself to isolate the faulty unit without bringing the whole network down.

When a new node is activated, or if a node has not received an invitation to transmit for 60 ms, or when a software reset occurs, The network causes a network reconfiguration by sending a reconfigure burst to terminate all activities on the network. Because the burst is longer than any other type of transmission, the burst will interfere with the next invitation to transmit, destroy the token and keep any other node from assuming control of the network. If any node does not receive the token within the Reconfiguration Time, the node will initiate a network reconfiguration. Each data packet is preceded by an integrity check of the receiver. Transmitter issues a Free Buffer Enquiry frame, which checks for free memory in the receiver. The receiver issues either a positive AC Knowledge or a NAC Knowledge. If an ACK is received, the data packet is transmitted followed by an ACK, if it is received error-free If a NACK is received, then the token is passed and the transmission is tried again on the next pass. As a result, probability for loss of message is minimized and the transmission reliability is enhanced.

(h) Transmission Normal Case

(i) Transmission Train Bus Disconnection

(j) Transmission Node Failure

RS 485 Transmission (k) Transmission signal • RS485 (half-duplex) •

Termination resistor = 120 ohm

•

Termination resisters are installed at both ends of line.

•

Bias resister = 1.2 kohm

•

Bias resisters are installed in only TIMS unit.

•

Shielded twisted cable (3 wires)

•

Signal lines consist of 1 data pair and a signal ground line.

(l) Wire

•

Signal lines shall be floating i.e. isolated from any frame ground or other circuits in TIMS unit or device. • Earthing of screen wire (shield) will be made in TIMS equipment at one point. (m) Network topology • Point to point connection •

Multi-drop connection

Node Architecture

Node Architecture

(n) Protocol

Polling / selecting based on HDLC Synchronous transmission (ISO3309/4335) is used in the: •

The primary station: TIMS (CU/LU)

• The secondary station: Each device (o) Transparency

The transmitter shall insert “0” bit after all sequences of 5 continuous “1”bits, and the receiver shall discard the inserted bit to achieve transparency (bit pattern independence within the two flag sequences).

(p) Baud rate • •

Baud rate = 9.6/38.4kbps(standard) Polloing cycle = 100/500 ms (standard) Table 1B-11-01-00-2

Device Baud Rate

Device

Baud rate (bps)

Propulsion System (CI) Brake system (BECU) Auxiliary power supply system (SIV) Air conditioning system Door Control System (DCU) ATC AVAS & PA TR

38.4k +/- 0.1% 19.2k +/- 0.1% 19.2k +/- 0.1% 9.6k +/- 0.1% 38.4k +/- 0.1% 19.2k +/- 0.1% 9.6k +/- 0.1% 19.2k +/- 0.1%

Polling cycle (ms) 100 100 200 500 200 500 500 500

Tramsmission Type RS485 RS485 RS485 RS485 RS485 RS232 RS422 RS422

(q) Signal code • NRZI code (viii) When the bit data is “0”, the signal level is inverted. (ix) When the bit data is “1”, the signal level is the same.

Fig. 1B-11-01-00-1

NRZI Code

(r) Frame Format Table 1B-11-01-00-3

Opening PAD

Flag 8 Bits

Frame Format

Address 1 Address 2 Control Information (Lower) (Higher) n Bits 8 Bits 8 Bits 8 Bits

CRC 16 Bits

Flag 8 Bits

Notes: 1. Opening PAD Two (2) flags before opening flag should be sent to the receiver to synchronise the receiving clock with the transmission signal. The number of flags can be increased until 15 (Maximum) by the request of each device. 2. Flag = 7EH 3. Address: (see also clause j below) Address is determined by individual specifications for each monitored device (except 0000H). Note: 0FFFFH is the Global (broadcast) address 4. Control = 13H (UI: Unnumbered information) 5. CRC = CRC CCITT-1(X16+X12+X5+1) Applicable range to calculate: from Address 1 to Information The most significant byte (MSB) of the CRC is sent first.

Address data (x) (xi) (xii) (xiii)

Setting TIMS => sub-system (Device): Set Address 1 and Address 2 which is equivalent to the device. Sub-system (Device) => TIMS: Set own Address 1 and Address 2. Usage Address 1: Select sub-system type. If all sub-systems are selected, set “0FFH”. Address 2: Select individual sub-system for selected type at Address 1. If all subsystems of same type are selected, set “0FFH”. Addresses for sub-systems

Device Propulsion System (CI) Brake system (BECU) Auxiliary power supply system (SIV) Air conditioning system Door Control System ('R' side) Door Control System ('L' side)

Address 1 (Lower)

Address 2 (Higher)

10H 20H 30H 40H 50H 50H

01H-02H 01H 01H 01H-02H 01H-04H 11H-14H

(s) Synchronous transmission

To perform the synchronous transmission, the receiver needs clock regeneration (synchronizations) circuits such as DPLL (Digital Phase Lock Loop) circuits

Synchronous Transmission Block Diagram

(t) Transmission data type Table 1B-11-01-00-4

Transmission Data Type

No

Data name

Abbreviation

Direction of transmission

1

Status data request

SDR

TIMS ==> Sub-system

2

Status data

SD

TIMS Sub-system

4

Trace data

TD

TIMS