* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Train-Lighting on IR
Electrical ballast wikipedia , lookup
Audio power wikipedia , lookup
Pulse-width modulation wikipedia , lookup
Electrical substation wikipedia , lookup
Current source wikipedia , lookup
Mercury-arc valve wikipedia , lookup
Electric power system wikipedia , lookup
Transformer wikipedia , lookup
Power inverter wikipedia , lookup
Stray voltage wikipedia , lookup
Electrification wikipedia , lookup
Variable-frequency drive wikipedia , lookup
Transformer types wikipedia , lookup
Voltage regulator wikipedia , lookup
Power engineering wikipedia , lookup
Opto-isolator wikipedia , lookup
Three-phase electric power wikipedia , lookup
Buck converter wikipedia , lookup
Power electronics wikipedia , lookup
History of electric power transmission wikipedia , lookup
Electric battery wikipedia , lookup
Voltage optimisation wikipedia , lookup
Mains electricity wikipedia , lookup
TRAIN LIGHTING SYSTEM Train lighting is one of the essential passenger amenities, which influence the image of Indian Railways.The basic purpose of train lighting is to provide light, air-conditioning and fannage in railway coaches using electric power. Following systems are currently in use in Indian Railways for accomplishing this function: 1.AXLE- DRIVEN / SELF GENERATION SYSTEM: WORKING ON 110 VOLTS D.C SUPPLY ------This system has proved more reliable and capable of meeting future increases in load. It has, therefore been adopted as standard for all future builds of selfgenerating coaches. In this system 3.0 kW /4.5KW alternators are driven through Flat/V-belts from axle. Lead acid batteries 110 volt, 120 AH capacity arranged from 3cell monoblock units, are provided in the BG coaches. Two number of emergency feed terminals boxes for BG and one number for MG coach are provided on each end wall of for interconnecting the coach to adjacent coach to receive power, in the case generation fails. One number emergency terminal box provided centrally on each side of underframe to facilitate charging of battery from external source. For BG air-conditioned coaches, 18 KW/22.75/25 kW brushless alternators are used. Two such alternators are used in ac-2 Tier / AC-3 Tier/Chair cars and only one alternator is used in I.AC coach. Batteries of 800/1100 AH capacity at 10 hour rate are used in ac-2 Tier /AC-3 Tier /Chaircar and 525 AH for IAC BGcoaches. A schematic layout for 110Volt DC system is attached in annexture1. Three Phase out put from 4.5 kW alternator mounted on the bogie of coach is fed to the regulator cum rectifier for rectifying the AC out put to DC and regulating the output voltage at different speeds and loads. The output from rectifier cum regulator on the under frame is brought through cables on the coach. The load is fed through four rotatory switches (RSW) and fuses connecting circuits L1, L2,F and SPM.L1 feeds the essential lighting load like lavatories,gangways,doorways and upto50% of lights in each compartment / bays corridor lights and night lights,L2 feeds remaining lighting loads F feeds the fan loads and SPM feeds Emergency Feed Terminals(FET). An external battery charging terminal (BCT) is provided to charge the battery from external charger, if battery is rundown condition due failure of alternator. ADVANTAGES Each unit being independent can work as slip coach In case of failure of generating equipments in 2 or 3 coaches, power can be drawn from adjacent coach by means of cable connection. Safe low working voltage. DISADVANTAGES High initial cost High maintenance cost and more plifirages A large amount of locomotive power goes for driving the generators BRUSHLESS ALTERNATORS Brushless Alternators are governed by RDSO specification No EL / TL /47 "C" for 4.5 and 3.0 KW alternators. Approved manufacturers for the alternators are: 1. KEL ( Kerala Electrical & Allied Engineering Industries ) 2. BEACON (Best & Crompton) 3. SIL (Stone India Limited ) 4. HMTD Engineering. 5. CGL (Crompton Greaves Limited) The Ratings in use are: 4.5 KW,120V or 30V for BG non-AC coaches 3.0 KW,120V or 30V for MG non-AC coaches 12.0 KW,120V for MG AC coaches 18.0KW,130V for BG AC coaches 22.75 /25 KW,130V Optimised alternator for BG ac coaches (New) 18 KW Brushless Alternator & Regulator (KEL Make) The brushless alternator is 3-phase Induction Alternator without any rotating windings, commutator or sliprings. Both the field windings and AC windings are located in the stator. The AC windings are distributed in 60 slots. The field coil spans half the total number of stator slots. The rotor is made up of silicon steel laminations and resembles a cogged wheel. The teeth and slots are uniformly distributed on the rotor surface (skewing the rotor axis) The alternator is equipped with 2 numbers of 200MM PCD 6groove V pulley and is driven through an axle pulley of 572.6 mm PCD, V belts type C-122 are used for drive. Technical Data of Alternator: Output Voltage 135V+ 5% on DC,side,(97V,3-phase AC) Current 140 Amp (Maxm)on DC side Cut in speed 550 rpm (30 Km/h with half worn wheels with pulley ratio 200/572.6 Maxm speed for 930 rpm for 135 AMP at 135V(51 full output Km/h) Maxm Speed 2800 rpm (156 Km/h) Class of F-Class Insulation Resistance 7.3 Ohm between field terminals RECTIFIER CUM REGULATOR UNIT OF 18 KW ALTERNATOR KEL- MAKE Power Rectifier (RP) : This consists of 6 silicon diodes connected in 3-phase full Wave Bridge. The 3phase output of the alternator is rectified by these diodes to give a DC output at terminal +L and - C. Each diode is protected against transient surge voltage by capacitor C1.The whole bridge is protected against high frequency surges by capacitor C3.The DC output is filtered by capacitor C2. Current Transformers (CT1,CT2&CT3) The Current transformers are used to sense the load current for the current limitor. When primary winding of each current transformer carries load current, the secondary winding feeds a 3-phase voltage to the rectifier RT2 in the regulator rake. Regulator Rake : The Regulator Rake consists of the following parts: Excitation Transformer (TE) This is single winding transformer with tapping for output and input.The transformer steps down the voltage for the field coils.The output of the transformer is taken to the field through the Magnetic Amplifier before being rectified by field rectifier diodes Magnetic Amplifier (MA) The magnetic amplifier forms the nucles of the regulator circuit.It works on the principle of saturation of magnetic core.The equipment has 6 sets of windings-- Two load windings 18-162 and 17-161 & Four control windings 10-11,26-27,20-40,29-30.(Out of these only 10-11 and 20-40 are used in the circuit.10-11 for voltage and current control and 20-40 for gain control) The field current passes through the load winding offers a variable impedance to the field circuit. Field Rectifier Unit The 2 silicon diodes D 4 and D3 acts as full wave rectifier for the field supply.These diodes conduct alternative,when the terminals 18 and 161 become positive with respect to the center tapping 19. The rectified current from the diodes is 2.End on Generation System INTRODUCTION: Indian Railways has introduced the End on Generation System to cater the increase in demand for faster trains having limited halts and improved passengers amenities- air conditioning, fluorescent lighting, catering from pantry cars in Rajdhani / Shatabdi Express services on several routes. Since requirement of power for operating air conditioning load, cooking ranges / refrigerators / bottle coolers in pantry car is considerable. The introduction of power cars equipped with Diesel Generating Sets is the only solution, now a day. CONNECTED LOAD FOR RAJDHANI EXPRESS: The connected load of typical Rajdhani Service is as under Sr. No. 1 2 3 4 5 Type of Coach AC 3 T AC 2 T AC First AC Pantry AC Power Car (Work) Total No of coaches 8 6 1 2 2 19 Load in Total load KW in KW 40.00 320.00 34.75 208.50 15.75 15.75 76.75 153.50 49.00 98.00 795.75 (800.00) Assuming a diversity factor of 0.7, The Maxm KW = 800 0.7 = 560 KW. CAPACITY OF POWER CAR: The old rakes of Rajdhani Express working in EOG system were provided with three power cars having generation and supply voltage at 415V, 3 Phase.To reduce the number of power cars from 3 to 2 and to feed the entire load of train from either of power cars, the capacity of DG sets has been increased from 125KW to 250 KW and generation voltage has also been increased from 415V to 750 V with a view to overcoming the voltage drop in feeding system. The 750 V power cars are the first and last vehicle in the EOG rake. POWER DISTRIBUTION IN COACHES: Two feeders run all along the entire rake through I.V couplers. Each coach on the rake is provided with the control, distribution and feeder changeover arrangements in the 750 / 415 V control panel. 750 Volt, 3 Phase supply is stepped down to 415-Volt supply system, contactors with interlocks are provided to pass the step-down transformer. The 415 V, 3phase supply is stepped down through 415 / 190 Volt, Delta-Star transformer separate panel is provided for control and distribution of 3 phase-4 wire, 190 volts for working lights and fans at 110 V, single phase. Emergency lights provided in the power cars comes ON automatically through No-Volt contactor which energises lamps from batteries as soon as main power supply interrupts for any reason. CAPACITY OF BRUSHLESS ALTERNATORS AND OF DIESEL ENGINE: Load on both the feeders 560 kW Load on each feeder = 280 / 0.8 KVA Required output of Alternator = 350 KVA 500 KVA capacity alternators are being used to cater the future increase in load, derating factor, unbalanced in the load e.t.c. Two types of Diesel Engines are being used for high capacity 750-Volt Power cars. Kirloskar Cummins.KTA- 1150 G -- 450 BHP at 380 C (427 BHP at 550C ) INTACH 3406 B -- 398 BHP at 550C Kirloskar Cummins Engines are coupled with brushless Alternator of KEC make (Kirloskar Electric Company Banglore). INTACH 3406 B engines are coupled with Brushless Alternators of KEL (Kerala Electrical) make. PROTECTIVE DEVICES: DIESEL ENGINE PROTECTION 1. 2. 3. 4. The following are the protective devices provided for Diesel Engine. High water temperature. Low water level in radiator. Low lubricating oil. Over speed. The high water temperature protective device cuts off the load automatically and the engine returns to idling speed and the other devices cut-out the load as well as shut-down the engine. All the protective devices are designed to give audio-visual indication when they operate. ALTERNATOR PROTECTION: Alternators are provided with following protective devices. 1. Alternator overload. 2. Under voltage. 3. Earth leakage. 4. Short circuit. FEEEDR PROTECTION Following devices are provided for feeder protection: 1. Feeder Earth leakage. 2. Feeder overload. FIRE-EXTINGUISHERS Each power car is provided with 2 nos of 5 Kg capacity dry power type fire extinguishers conforming to specification IS-2171.One of the fire extinguishers is located in the alternator and the other in the engine room. ADVANTAGES: Low initial cost compared to Axle-Driven Generation system. Low maintenance cost. Higher efficiency Less current due higher voltage Better lighting and fannage. Additional coaches may be attached to the train as tare weight of the coaches is reduced. No power is required to drive the axle generators. DISADVANTAGES: Any disconnection of the feeder will cause a failure Failure of both the DG sets will result in total breakdown. Revenue earning space is occupied by power cars and operating staff. Storage of diesel oil poses a fire hazard. Interchangeability of coaches is restricted. 3.MID-ON GENERATION SYSTEM By providing DG sets of adequate capacity in a coach at the centre, power can be supplied throughout the train by feeders. This system has been introduced in branch line trains, which are essentially slow speed trains having frequent stoppages and is operating satisfactorily. There are two DG sets of smaller capacities (30KVA/12.5KVAand 3-phase, 415V, 50C/S power is generated. Only one DG set runs at a time. One transformer of matching capacity kept in the generator car itself, steps down the generated voltage415V, 3-phase to190 V, 3-phase, star system that is supplied to all coaches.110V is obtained between a line and earth. The advantages and disadvantages of this system are same as those of EOG system. The branch line trains are more theft prone and necessitates its adoption. 4.HEAD-ON GENERATION SYSTEM This system is being proposed to be adopted in electrified section. Power is to drawn from the transformer of the electric locomotive through an auxiliary winding and supplied to all coaches. Different forms of this system are being considered.In one form ,single phase power at 750 Volts is to be supplied to each coach which will be provided with a transformer for steeping it down to a suitable level,and a rectifier for converting it into 110V DC.There will be battery back-up also for maintaining continuity of supply. BATTERIES USED IN TRAIN LIGHTING Conventional Lead Acid cells for T / L applications are governed by IS 68-18 Types of cells in use for train lighting and coach air-conditioning are as under: Capacity of battery in AH at Type of coach 270C at 10 Hours Rate where generally used 120 110V,BG 210 24V,MG 320 24V,BG 450 MG AC coach 525 1st Class AC coach 800 II AC BG coach 1100 II AC/AC 3 Tier BG coach Principle of operation: In a charged lead acid cell +ve active material consists of lead peroxide (PbO2) and the -ve of spongy lead (Pb). Dilute sulphuric acid (H2SO4 +H2O) serves as electrolyte. The overall reactions inside the cell during discharge and charge are represented most conveniently by a reversible equation as follows: PbO2 + Pb + 2H2SO4 During discharge-- ↔ 2PbSO4 + 2H2O The PbO2 on the +ve plates as wellas the spongy lead on the -ve plates are converted into PbSO4.In this process, H2SO4 acid is consumed and H2O formed. Consequently, the specific gravity of the electrolyte falls, the extent of fall being proportional to the ampere-hours taken out. The process causes at first a slow, and then a faster voltage drop, until a permissible lower limit (final discharge voltage )is reached,which depends on the rate of discharge currrent.The amount of ampere-hours (constant current x time ) taken out is called the capacity of the cell at this rate. The chemical process during charge is the reverse of that during discharge. The PbSO4 on the +ve plates is converted into PbO2 and the PbSO4 in the -ve plates into spongy lead. H2SO4 acid is formed and H2O consumed. The specific gravity of the electrolyte rises.there is at first a slow, later a faster rise of cell voltage. Electrolyte: --It is dilute Sulphuric Acid of Specific Gravity 1.18-1.22. It can be prepared by mixing concentrated battery grade Sulphuric Acid as per IS:266 of sp.gr.1.835 with Water of approved quality as per IS:1069. To get approx.100 Lts of Electrolyte of sp.gr.1.18 , water 86 Lts + Acid 17 Lts (by weight) To get approx.100 Lts of Electrolyte of sp.gr.1.22 , water 82 Lts + Acid 21 Lts (by weight) --In our country, the standard temperature for measuring sp.gr. Of any electrolyte is 270C.As such the correction is as under Correction For every 100C above 270C,add 0.007 or 7 points to the sp.gr.reading on the hydrometer and for every 100C below 270C,substract 0.007 or 7 points from the readings. Features Affecting Life of L.A.Battery:--- 1. 2. 3. 4. Necessity for frequent topping up cells Leakages of electrolyte on lid and on container body Failure of one cell in monoblock unit Undercharging / Overcharging : SMF (Sealed Maintenance Free) Battery: To overcome problems of frequent topping up of electrolyte, SMF lead acid batteries have been developed and are under trial.These batteries are governed by RDSO specification EL/TL/59.Electrolyte in these batteries is in immobilized form and can be used in any position-horizontal or vertical. Such battery requires only periodic cleaning of terminals. It has self sealing vent plug, which normally does not open out in service. Maintenance: Train lighting batteries of coaches by the very nature of service conditions can not be expected to have steady rate of charge / discharge,left to idle for long duration or charged at higher rates.The running maintenance of storage batteries falls under 4 categories: Trip Examination--1. To know the condition of cells during "Trip Examination"some cells in a battery are treated as pilot cells. On arrival of train in the maintenance line, the disconnect at inter vehicle connections. Record the specific gravity of "pilot cell" in each battery. 2. Check and record of total voltage of the battery. 3. Keep vent plug tight and ensure the healthy condition of battery. 4. Check anti-theft arrangements and ensure it. Fortnightly Maintenance: 1. Clean the interior of battery box. 2. Clean the cell tops and deposit of sulphate,if any,in intercell and end cell connections 3. Remove end cells connectors, clean the connecting surface both in cell and connector thoroughly and provide back. Check proper crimping of terminal. 4. Check whether cell packing is tight and provide additional packing, if necessary. 5. Apply petroleum jelly on intercell connections and cell connections 6. Check battery fuse condition 7. Check battery boxes condition. 8. Charge the battery and on completion of charging record the sp.gravity of individual cells 9. Record each cell voltage and total voltage on full load of the coach Quarterly Maintenance: In addition to the fortnightly maintenance 1. Switch off load and charge the cells at 50% of normal rate of charge i.e. at 1/20th the rated capacity of cells. Record hourly cell voltage and sp.gravity reading. 2. Terminate charging when 3 successive readings are constant. Record sp. gr. and no load voltage of each cell 15 minutes after terminating charge. Intermediate Overhaul -- Facilities required in major dopots for maintenance :