Difference between CRH2 EMU and CRH5 EMU

1. power supply and traction system and equipment of CRH2 emu CRH2 emu is manufactured and produced domestically by Sifang co., ltd. EMU consists of 8 cars, including 4 motor cars and 4 trailers; The first vehicle has a cab, which can drive in both directions. The head car length of EMU is 25.7m, the middle car length is 25m, the main factory is 21.4m, the car body width is 3.38m, and the car body height is 3.7m m. The cars planted in No.4 and No.6 are equipped with pantographs and accessories. When the installation height is 4m, the working height of pantographs is the lowest 4888mm, the highest 68mm and the highest 7, mm. When the EMU is in normal operation, one bow is used for current collection, and the other one is used for standby, which is in a folded state. No.2, No.3, No.6 and No.7 cars are motor cars, and there are traction converters and traction motors, and there are traction transformers under No.2 and No.6 cars. 1, 4, 5 and 8 are trailers. Basic principle of power supply traction system for CRH2 EMU The traction system is mainly composed of pantograph, traction transformer, traction converter and traction motor. The 25KV high-voltage alternating current connected to the power grid is transmitted to the traction transformer through the pantograph, which will be converted into 15V alternating current. The stepped-down alternating current is then input into the traction converter, and after a series of treatments, it becomes a three-phase alternating current with controllable voltage and frequency, which is transmitted to the traction motor to traction the whole train. EMU has two relatively independent main traction systems, which form a power unit. Under normal circumstances, both traction systems work. When one traction system fails, it can automatically cut off the fault source and continue to run. There are two sets of EMU braking systems. One set is electric braking, which converts the traction motor into a generator, that is, regenerative braking. One set is air braking, which converts electric instructions into air instructions and sends them to the brake cylinder for braking. When the train speed is high, the electric braking is implemented, and when the train speed is low, the air braking is implemented. The switching of braking mode is controlled by the microcomputer system. When the driver carries out the braking command through the brake controller on the driver's platform, the braking point signal first reaches the vehicle computer system and then is transmitted to the braking control system. The braking control system automatically implements air braking and electric braking according to the train speed. The composition of the electric braking system is consistent with that of the traction system. Composition of power supply traction system and arrangement of modules for CRH2 EMU; EMU takes 2 motors and 2 trailers as a basic power unit. The traction drive system of a basic power unit is mainly composed of grid-side high-voltage electrical equipment, a traction transformer, two traction converters and eight three-phase AC asynchronous traction motors. The whole train consists of 2 pantographs, 2 traction transformers, 4 traction converters and 16 traction motors. When the train is normal, one pantograph is raised for operation, and the other pantograph is reserved. The power supply equipment is arranged on the roof of No.4 and No.6 cars, and the electric drive equipment is arranged on No.2, No.6, No.3 and No.7 cars. The main circuit between vehicles is connected by high-voltage cable and high-voltage cable connector. UHV cable connectors are installed on the roofs of the rear of No.2 car, the front and rear of No.3 car, the front of No.4 car, the rear of No.5 car and the rear of No.6 car. Inclined cable connectors for UHV cables are installed on the roofs of No.4 car and No.5 car for convenience of taking off and hanging, and UHV cables are connected through the high-voltage connectors. Install pantographs and emergency grounding switches on the front roofs of cars 4 and 6. Electrical equipment mainly includes: pantograph, main circuit breaker, lightning arrester, current transformer, grounding protection switch, etc. Dynamic performance parameters of power supply and traction system for CRH2 EMU The maximum operating speed of CRH2 EMU is 2km/h, the maximum test speed is 25km/h, and the total traction power of EMU is 48kw. The starting acceleration of the EMU with fixed capacity load on the straight track is .46 m/S2; When running at 2km/h, its reputation acceleration is not less than .1m/s2. When the EMU loses 25% of the starting power, the equilibrium speed on the straight track can be greater than 2 km/h.. The EMU can also operate normally under the headwind of 15m/s wind speed. CRH5 traction drive The traction system of CRH5 EMU adopts AC-DC-AC drive mode, which is mainly composed of pantograph, main circuit breaker, traction transformer, traction converter and traction motor. The pantograph is connected with 25kv high-voltage alternating current through the power grid, which is transmitted to the traction transformer and reduced into 177v alternating current. The pressurized alternating current is then input into the traction converter, which is inverted into three-phase alternating current with controllable voltage and frequency, and is delivered to the traction motor to traction the whole train. The main transformer of traction system of CRH5 EMU adopts oil cooling mode, and the traction converter adopts mature IGBT technology. The power of asynchronous traction motor is 55kw, and the traction force is transmitted by universal shaft. EMU has two main traction systems, and each traction unit is equipped with a complete collector, traction and auxiliary system to realize the required traction and auxiliary circuits. One unit consists of three motor cars and one trailer (M-M-T-M) and the other unit consists of two motor cars and two trailers (T-T-M-M). Each power unit has a main transformer and a pantograph. In normal operation, each train only starts one pantograph. The traction equipment of each traction power unit consists of the following equipment: 1. A high-voltage unit with pantograph and protective device; 2. A main transformer; 3. Two or three sets of main traction kits of IGBT water cooling technology; 4, four or six asynchronous traction motors, underframe suspension, the maximum design load of 55kw (power at the rim). Because each motor is driven by a Dulu traction inverter, there is no need to reduce the load when the wheel diameter difference between wheelsets in the same vehicle is 15mm at most. Each emu is equipped with two traction motors. Under normal circumstances, both traction systems work. When one traction system fails, it can automatically cut off the fault source and continue to run. Traction/electric system characteristics Under normal load conditions (fixed number of passengers), straight lines, average wheel wear (that is, the wheel diameter is 85mm) and the grid voltage is within the range of 22.5KVAC-29KVAC, The traction performance of the train is as follows: 1. The average starting acceleration (-4km/h) is .5m/s2, the residual acceleration at 2km/h is .11m/s23, and the residual acceleration at 22km/h is .9m/s24, 25km/ The residual acceleration at h is .5ms25, the average maximum wheel wear adhesion factor is .226, the creep slope (1% traction) is 3‰7, and the creep slope is 27‰ (continuous operation) ~3‰ (running at 73km/h for 25 km) under the condition of two traction converters failure or one traction transformer failure (6% traction power can be obtained); 8. The maximum traction power at the wheel circumference is 55kw；; 9. The maximum traction at the wheel circumference is 32kn1, and the maximum braking power at the wheel circumference is 5785kw. The train is equipped with regenerative braking, which can work in the speed range of 22 to 1km/h.. In the electric phase separation section, the electric braking will not stop, but it will supply the regenerated current to the auxiliary converter and dissipate the energy through the braking resistor, which is installed on the roof and naturally ventilated. The purpose of this design is to allow resistance braking for up to 1 minutes. Regenerative braking can be restarted at the end of electric phase separation. If the electric phase separation section lasts more than 1 minutes, the electric braking will stop completely and the air braking will be automatically activated. The train is equipped with air-cooled disc brakes, two on each moving axle and three on each towing axle, and a spring-controlled parking brake. EMU usually uses a combination of electric braking and air braking, and the emergency braking is only air braking. The electric brake works in the speed range of 2km/h to 1km/h, and when the maximum electric brake is reached, The maximum braking force and power at the wheel circumference are as follows: 1. The maximum braking force at the wheel circumference is 25kn2 and the maximum braking power at the wheel circumference is 5785kw. The maximum common braking and emergency braking performance are the same: the initial speed is 2km/h:1, and the average deceleration is .79m/s22. Braking distance ≤ 2, m, initial speed ≤ 16km/h1, average deceleration ≤ .79m/s22, and braking distance ≤ 1,4 m The traction equipment of each power unit consists of the following equipment: 1. The high-voltage electrical unit has power receiving equipment, protection device and main transformer, and is installed on TTP and TTPB vehicles. The main transformer adopts forced oil cooling. 2. The first traction power unit has three traction/auxiliary converters, and the second traction power unit has two traction/auxiliary converters, each of which drives two traction motors. The traction/auxiliary converter obtains adjustable DC voltage and drives the traction and regenerative braking of asynchronous traction motor. During the over-current phase separation, the regenerative braking stops working for a short time, and the excessive electric braking resistor is put into use. Each motor car is equipped with two asynchronous traction motors, and the underframe is suspended. The designed continuous power of a single motor can reach 55kw, and the wheel diameter difference (on the same axle) is close to 3mm, which can also provide 5kw load. 3. A traction controller can complete the following functions: control equipment to send traction/braking commands; Control the intermediate DC line voltage and the power factor of the pantograph input; Control the traction/braking torque of the motor to protect the power equipment; Self-diagnosis of the controller itself; 4. Electrical devices installed on IM2 and IMH vehicles, such as 1hz resonant brakes and instantaneous electric braking resistors. High-voltage electrical high-voltage electrical system collects 25kv current from overhead contact lines to provide power for traction equipment and other facilities, and control, detect and protect the high-voltage system. These circuits are located on TTP and TTPB cars and consist of pantograph, main circuit breaker, lightning arrester, network end detection device and so on. The characteristics of traction transformer are: 1. Large capacity and miniaturization; 2. The installation method adopts horizontal horizontal organization suspended under the floor of the car body; 3. The oil storage tank is placed on the side to reduce the height of the transformer; 4. It is resistant to mechanical impact and can withstand the impact acceleration of 3g in the horizontal direction, 2g in the horizontal direction and 1g in the vertical direction; 5. The overall insulation level is F-class; 6. The high impedance makes the space magnetic field inside the transformer very strong, and a large number of non-magnetic and insulating materials are used for structural parts. 7. The coil wire is insulated by Nomex paper, which has high heat resistance and high mechanical strength. 8. The winding structure is fully split to meet the requirements of electromagnetic coupling. 9. The cooling method is forced guided oil circulation air cooling. 1. Ester grease with high ignition point is used as the cooling medium. Traction transformer structure: the transformer adopts core horizontal structure. The internal structure is mainly composed of iron core, coil body and lead wire, and the external structure is mainly composed of oil tank and oil storage tank, cooling system and components. Main transformer control The main transformer control is completed by the high voltage box. The high-voltage box is installed under the No.3 and No.6 cars, and it includes electromechanical equipment and sensors to manage the high-voltage circuit. The high-voltage box can also protect the traction transformer. Functions of high-voltage cabinet:-Insulate traction/auxiliary converter-Manage transformer auxiliary equipment-Ensure rapid protection function-Ensure remote input/output to train network control system. 1. Layout and classification of electrical equipment in CRH2 EMU. The equipment of CRH2 EMU No.1 (T1c) includes speakers, getting on and off prompts and information display screen, as a sign, and is illuminated through the platform, but it can be illuminated, broadcast, temperature and vibration. The arrangement of electrical equipment under the vehicle includes: signal receiver of driving position, receiver, signal receiver, ventilation device, variable frequency gas box of ventilation device, water tank, air conditioning device, dirt box, outdoor unit of cab air conditioning device, air conditioning device, auxiliary power supply device, brake control device, battery valve for other surface cleaning, and control loop junction box. The equipment in CRH2 EMU No.2 (M2) includes telephone, toilet indicator light, speaker, pass-through lighting, passenger room lighting, various power sockets, etc. The off-board equipment includes: auxiliary electric compressor, traction motor connector, ventilator for cooling traction motor, ventilation device, variable frequency gas box of ventilation device, socket for external power supply, converter, contactor box, garbage inlet, control loop junction box, air conditioner, high-voltage control box, main transformer, traction converter, brake control device, electromagnetic valve for cleaning tread, grounding reactor, ventilator for cooling traction motor and control loop junction box. The equipment of No.3 and No.7 (M1) of CRH2 EMU includes crew control switch, emergency storage battery, passing station lighting, passenger room lighting, broadcasting, electrical integrated cabinet, etc. The off-board equipment includes: traction motor circuit connector, electric ventilator for traction motor, continuous ventilation device, dehumidifier, main converter, ventilation device inverter, water tank, air conditioner, dirt box, electric air compressor, brake control device, grounding resistor and control circuit connection box. The underpass of CRH2 EMU No.5 (T1K) includes: connecting ventilation device, ventilation device inverter, dehumidifier, auxiliary circuit connector, water tank, air conditioner, dirt box, electric air compressor, brake control device, electromagnetic valve for tread cleaning and control circuit connection box. The electrical equipment of CRH5 EMU head car includes: traction motor, air conditioning equipment, 15v circuit breaker box, medium and low voltage equipment rack, driver's desk, 14KVA auxiliary power supply, 24KW charger, electrical cabinet rack, transformer, air conditioning box, coupling, hydraulic unit box, brake unit, brake control unit, compressed air box, battery box, air compressor, toilet dirt box, bus logo and power bogie. The electrical equipment of CRH5 EMU bus without pantograph on the roof includes: traction motor, four-quadrant inverter, unit indicator, brake rheostat, medium and low voltage equipment rack, electrical cabinet rack, heating system converter, motor driver, hydraulic unit box, brake unit, toilet dirt box, bus logo, power bogie, connecting rod and air conditioning equipment. The electrical equipment of CRH5 EMU bus with pantograph on the roof includes: 1.5/2.3kv converter, Air conditioning equipment, pantograph, 25kv circuit breaker, grounding circuit breaker, 25kv resistance box, roof short circuit breaker, 25kv rotary head, 25kv transformer, converter, traction converter, medium and low voltage equipment rack, charger, replica, heating converter, sensor, toilet sewage box, water tank, brake unit, water pressure unit box, battery box, brake control unit, compressor cooler, bus logo, etc. fluorescence