Maintenance Manual AC DC EMU (Siemens) - Draft for comments PDF

CAMTECH/E/13-14/MM AC-DC EMU/1.0 1 CHAPTER 3 TRACTION CONVERTER CUBICLE 3.1 TRACTION CONVERTER CUBICLE The traction converter cubicle is a complete...

CAMTECH/E/13-14/MM AC-DC EMU/1.0 1 CHAPTER 3 TRACTION CONVERTER CUBICLE 3.1 TRACTION CONVERTER CUBICLE The traction converter cubicle is a completely assembled unit installed in the HT compartment of the motor coach. The traction control unit (TCU) is situated inside the cabinet. The technical details are as following: Nominal input voltage 2 x 950 V AC, 50 Hz / 1500V DC Input voltage range in AC mode 627 V – 1083 V AC Which is related to a line voltage from 16.5 – 28.5 kV Input frequency range in AC mode 46Hz – 54 Hz Input voltage range in DC mode 800 V – 1800 V DC Nominal DC link circuit voltage AC Mode 1800 V traction operation DC Mode 1500 V Power factor in AC at different loads Approx. unity and line voltages Figure 1- TCC 3.2 ELECTRICAL SYSTEM The traction converter works on dual voltage system i.e. line input of 1500V DC or 950V, 1ph, 50Hz AC (25KV AC line). The converter consists of two four-quadrant chopper, one DC link, two PWM Inverters each delivering two traction motors. The converter also includes DC link capacitors, contactors, transducers, blowers etc. The function of the traction converter is controlled and monitored by Siemens’ Traction control unit (TCU) SIBAS® 32S. Maintenance Manual for AC-DC EMU (Siemens) Chapter 3 2 CAMTECH/E/13-14/MM AC-DC EMU/1.0 Figure 2 - Schematic of the traction converter Chapter 3 Maintenance Manual for AC DC EMU (Siemens) CAMTECH/E/13-14/MM AC-DC EMU/1.0 3 3.2.1 Functional sections of the traction converter in AC Mode The traction converter consists of the following functional sections in the AC Mode operation: Input and pre-charging Four-quadrant chopper DC link circuit Capacitive earth-fault registration Pulse width modulated inverter & Braking chopper Figure 3 - Input section in AC mode of operation Input and pre-charging Refer to Figure for the schematic of the functional input section in AC Mode. Two poles (K1.1 and K1.2) of a double pole contactor (K1) isolate the transformer and 4QC module from each traction winding of the transformer. A pre-charging unit is connected in parallel to this main contactor. The pre-charging unit consists of a single pole pre-charging contactor (K4), One pole K4.1 connected in series with a pre-charging resistor (R31). The pre-charging resistor comprises of two resistors R31.1 and R31.2 in parallel. When the converter is put into operation, first the DC link capacitor of the inverter is pre-charged before the main contactor is closed using diodes in 4QC modules. This prevents the high inrush current, which would result if the input voltage was suddenly switched onto the empty converter. The main contactor is switched on after the DC link voltage has reached 90 % of the theoretical final charge. Four Quadrant Chopper Module (4 QC) A four-quadrant chopper consists of a bridge as shown below in Figure. The purpose of the 4QC is to transform the input voltage (generally single phase AC from the transformer) into a controlled direct voltage for the DC link circuit. The term 4QC signifies that the phase angle between voltage and current is freely adjustable while driving as well as while braking. Through the combination of phase situation and mode of operation all four operational quadrants can be obtained. Maintenance Manual for AC-DC EMU (Siemens) Chapter 3 4 CAMTECH/E/13-14/MM AC-DC EMU/1.0 The IGBT’s are used as switches with a high closing sequence. The function is described exemplarily for rectifier-operation starting from a current less situation. To build up a current in the self-inductance of the transformer LN one of the two IGBT’s A2 or A3 (positive half-wave, A1 or A4 at the negative half-wave) is triggered. During this the secondary side of the transformer is short circuited. As soon as the current has reached the desired value the IGBT is blocked. The current continues to flow via the freewheeling diode into the DC link circuit and is reduced by this (UD  UN). Afterwards the process starts again and during it the IGBT’s are used alternately to put equal thermal burdens on them. Number of 4 QC per Traction Converter 2 Cubical (TCC) Semiconductor IGBT Type of phase module SIBAC BB S P 1500 FL Pulse frequency 750 Hz Figure 4 - Four Quadrant Chopper Module Pulse Width Modulated Inverter The IGBT’s can be essentially defined as basic switches with a high clock frequency. This means it is possible to connect 3 output terminals U, V, W as required to the + or of the voltage DC link Cd. The switching sequences are selected so that a sinusoidal current is obtained. The voltages between two output terminals are now observed. The maximum possible amplitude of the phase to phase output voltage is a function of the magnitude of the DC link voltage Ud. The RMS value of the output voltage can be reduced by clocking. This clocking comprises brief turn-off operations within a basic fundamental. The frequency, with which the output waveform is repeated, is the same as the PWM inverter output frequency. When braking, the motor torque direction opposes the direction of rotation. There is considerable phase shift between the voltage and current. By entering the basic fundamental, the PWM inverter adjusts the phase between the voltage and current. Chapter 3 Maintenance Manual for AC DC EMU (Siemens) CAMTECH/E/13-14/MM AC-DC EMU/1.0 5 Figure 5- Pulse Width Modulated Inverter Number of PWMI per TCC 2 Number of traction motors per PWMI 2 Semiconductor IGBT Type of phase module SIBAC BB S P 1500 FL Pulse frequency Variable, up to 800Hz Brake Chopper Protection resistors are externally connected to the brake chopper for protection. When any serious fault is detected by SIBAS, it turns off all IGBT modules and fires chopper. During this, entire DC link gets discharged through protection resistors. This is only for over voltage protection of the DC link & no full duty braking resistor. Number per TCC 2 (per PWM inverter a double module (PWM inverter, brake chopper) Semiconductor IGBT Type of phase module SIBAC BB S P 1500 FL Pulse frequency 250 Hz Capacity of DC link circuit 12 mF -0 % 10 % Inductance of line reactor 6 mH -0 % to10 % Control Voltage Control voltage range 110 V DC Max operating current at nominal voltage 77 V to 137.5 V DC, 10 Amp. Auxiliary supply voltage 3AC, 415V, 50Hz Continuous power demand approx. 6.2 kW Maintenance Manual for AC-DC EMU (Siemens) Chapter 3 6 CAMTECH/E/13-14/MM AC-DC EMU/1.0 Power rating Parameter Continuous rating Short time rating (2 min) Input Power per 4QC 620 kW 720 kW Input Current per 4QC 764 A 903 kW Output Power per PWMI ( AC & DC) 535 kW 630 kW Output Current per AC 322 A 371 A PWMI DC 400 A 446 A Out put voltage (L-L) AC 1217 V 1217 V DC 986 V 1024 V Capacity of DC link circuit : 12 mF -0 % +10% ( 4 X 3 mF) Inductance of line reactor : 6 mH 0 % to +10 % Air Flow : 1.9 m3/s ( 0.95 m3/s per blower) Air Flow required : 1.6 m3/s Forced Ventilation Traction Converter Cabinet is a forced air-cooled system. The airflow direction is shown in figure given below. Figure 6: Principle of forced ventilation Chapter 3 Maintenance Manual for AC DC EMU (Siemens) CAMTECH/E/13-14/MM AC-DC EMU/1.0 7 3.3 LIST OF COMPONENTS Type Number Description Functional Designation Quantity Part no Unit in cabinet per TCC SP1500FL IGBT Module 4 Quadrant A1, A2, 4 A5E00281205 –Single Choppers A11,A12 Parallel SD1500FL IGBT Module PWM A3, A5, 4 A5E00281211 –Double Inverters A13,A15 4PK9904-7AB Line Filter DC Line L1 1 A5E00465421 Choke LTHS-1250-2P Line Contactor DC Main- K6 1 A5E00422750 DC /Line- Contactor LTHS-800-2P Line Contactor AC Main- K1 1 A5E00307978 AC /Line- Contactor LTC-250-2P Pre-charging DC – K5 1 1012253 Contactor DC Precharging Circuit LTC-250-1P Pre-charging AC Pre- K4 1 A5E00406971 Contactor AC charging Circuit 2CS7-410- Main Blower Main M1, M2 2 A5E00296015 1RG11-0KK3 blowers for cooling 148DH9LM Auxiliary Auxiliary M11, 3 1000263 18230 Blower blowers for M12,M13 churning air DCMKP 2.2/ DC Link DC Link C1, C2, 4 A5E00374704 3mF or Capacitor C3,C4 E56.M45- 305680 P354.1-IGBT DC/DC IGBT A91, A92 2 A5E00296016 Power Driver card Supply power supply CS1000BRVE Current AC/ DC U1, U2, U3, 8 A5E00307975 or LTC600- Transducers Input output U4, U5, SFC-SPxx currents U6,U7, U8 A5E00303286 Voltage DC Voltage U31, U32, 4 A5E00303286 Transducers monitoring U33, U34 TV 1164 (CT) Intermediate System T4, T5 2 5E00422663 Transformer current Current monitoring Maintenance Manual for AC-DC EMU (Siemens) Chapter 3 8 CAMTECH/E/13-14/MM AC-DC EMU/1.0 Type Description Functional Designation Quantity Part no Number Unit in cabinet per TCC TV 1162 Intermediate System T3 1 A5E00422668 (VT) Transformer Voltage Voltage monitoring BNV SIBAS Filter SIBAS Z1 1 621961 05.110.d/ Power 0.5 X2 Supply Filter 31138210 Temperature Air Inlet B1 1 279729 Sensor – Air Temperature Inlet PVR900T or Pre-charging AC/ DC Pre R31.1,R31.2, 4 A5E00422669 GBS 60/370 Resistor charging R32.1,R32.2 60R +/-5% Circuit PVR160 or Discharge Discharge R42 1 A5E00422670 GWS 300 SB Resistor DC and Earth 33K +/-5% Link Fault Detection PVR160 or Discharge Discharge R41 1 A5E00422672 GWS 300 SB Resistor DC and Earth 99K +/-5% Link Fault Detection B25835- Grounding DC Link C75 1 A5E00122720 S2224-K057 Capacitor Discharge and Earth Fault Detection 3RT10172K Contactors Blower K92, K95 2 1012617 F420LA0 for Blower Circuit 3RH11222K Auxiliary Auxiliary K51-K53 3 1010736 F400LA0 Contactors Circuit 6FH4742-1A SIBAS 32 S Traction A100 1 A5E00299514 Control Unit 343434 EMC DC link C71 1 343434 capacitor circuit Chapter 3 Maintenance Manual for AC DC EMU (Siemens) CAMTECH/E/13-14/MM AC-DC EMU/1.0 9 3.4 PHOTOGRAPHS OF MAJOR COMPONENTS TCU with control connectors IGBT module 4 Quadrant chopper IGBT module PWM Inverter IGBT module Maintenance Manual for AC-DC EMU (Siemens) Chapter 3 10 CAMTECH/E/13-14/MM AC-DC EMU/1.0 Position of K1 and K6 contactor Figure showing location of main blowers Assembly of C1 and C2 seen from contactor side of cabinet Assembly of C3 and C4 seen from SIBAS side of cabinet Chapter 3 Maintenance Manual for AC DC EMU (Siemens) CAMTECH/E/13-14/MM AC-DC EMU/1.0 11 Main blower motor cable connectors Current transducers with bus bar Auxiliary transducer Auxiliary contactors Auxiliary blowers Pre-charging resistor plate assembly Maintenance Manual for AC-DC EMU (Siemens) Chapter 3