DF8BJ diesel locomotive is an AC drive six-axle trunk freight diesel locomotive jointly developed, designed and manufactured by Capital Machinery Company and Zhuzhou Institute. The rated power of locomotive is 37 10kW, wheel diameter 1050mm, axle load 25t, maximum running speed 120km/h, maximum starting traction 560kN, continuous traction 4 10kN and constant power speed regulation range 22 ~160kn. Through the minimum curve radius of 145m, the locomotive is equipped with 16V280ZJG EFI diesel engine, and the maximum running power is 4000kW(5500 HP). DF8BJ diesel locomotive was developed in 200 1 year, and produced 1 set, with car number 000 1. Fixed in Zhengzhou North Shangqiu in 2002. In 2006, the prototype was inspected, disassembled, repaired and then put into the company.
2. The whole locomotive DF8BJ diesel locomotive is a load-bearing structure with inner corridor and truss side wall. The upper part of the car body is divided into six rooms by five partitions, which are I-end cab, electrical room, power room, cooling room, auxiliary room and II-end cab in turn. The lower part is an oil tank, a storage battery box and two interchangeable three-axle bogies. The control functions of the two cabs are the same, and the equipment layout is basically the same. There is a bridge and a driver's seat. The driver console is equipped with driver controller, automatic brake valve and separate brake valve of braking device, various control buttons, instruments and signal display devices, etc. There are also some electrical appliances, such as heaters, electric fans and electric stoves. Brake resistance cabinet, electric control cabinet, traction converter cabinet, three items of equipment and a toolbox are installed in the cab. The starting gear box of the auxiliary transmission mechanism is connected with the ventilator of the starting generator and the traction motor of the front bogie. The valve mounting frame and three equipment and tool cabinets are located on the back wall of the electrical room. The electric cabinet is installed on the back wall of the cab, where it can be overhauled. The traction converter cabinet is installed in the power room between the starter generator and the electrical cabinet, and mainly includes diesel engine, traction generator set, air filter, fuel filter, oil transfer pump, auxiliary lubricating oil pump, pipes and valves of cooling water system, expansion water tank, etc. A car body ventilator is installed on the side wall for discharging. The cooling room is equipped with radiator group, cooling fan and hydrostatic motor. The lower part of the radiator group is provided with auxiliary rooms such as hydrostatic gear box, traction motor ventilator of smoke bogie in the back room, lubricating oil filter, lubricating oil heat exchanger, air compressor, etc. The left picture shows the circulating water pump of the preheating boiler, and the right picture shows the preheating boiler. The left side of the front partition wall is provided with an air purification device (double tower type). The left side of the rear partition wall is provided with an escalator that can reach the ceiling, and the right side is provided with a preheating boiler control box. There is a hand brake transmission device in the middle of the lower part and trackers on both sides of the lower part. The oil tank is hung in the center of the lower part of the frame, and batteries are installed on both sides of the oil tank. The auxiliary transmission device of the main air cylinder is mainly composed of mechanical transmission, hydrostatic transmission and DC motor drive. The mechanical transmission device consists of a universal shaft, a starting gearbox, a transmission shaft, a rear gearbox, an input shaft, an output shaft and a coupling. The hydrostatic gearbox is driven by the crankshaft at the free end of the diesel engine and connected by a transmission shaft. The rear gearbox has three output shafts, two of which drive two hydrostatic pumps with the same structure, and the other drives the rear ventilator through a nylon rope transmission shaft. The cooling fan is driven by hydrostatic transmission technology, and the hydrostatic motor realizes stepless speed change and automatic control.
3. Traction electric drive system
(1) Traction Circuit The main drive system of DF8BJ internal combustion engine includes rectifier, three-phase traction inverter module, resistance braking device and overvoltage chopper switch module. Various traction circuits such as voltage and current sensors and input contactors include the power supply circuit from the traction generator to the traction motor, the protection circuit and measurement circuit of the traction circuit, and the excitation circuit of the traction generator. The locomotive AC traction drive system adopts bogie control mode. The armature of the traction generator is double-winding, and two groups of three-phase alternating current generated by the windings are converted into high-voltage direct current through two groups of independent traction rectifier units, and then converted into three-phase alternating current through the traction inverter to supply power to three parallel traction motors on the bogie. The locomotive is equipped with two sets of resistance braking units, which are respectively connected in parallel in the middle direct current path of two traction converters.
(2) The traction generator and shaft-assisted generator locomotive adopt TQFR-4000 three-phase AC brushless excitation synchronous traction generator, and the stator of the traction generator adopts star-shaped double-winding structure with rated power of 4000kV? A the locomotive with rated voltage of 2030V and rated current of 2X570A and rated speed adopts ZQF4 13 starter generator with rated power of 90kW, rated voltage of 1 10V and rated speed of 1078~ 1 000 r/min. When the diesel engine starts, the motor runs as a series motor, that is, the starting winding works and the battery supplies power. After series excitation, the motor is dragged by the diesel engine and becomes a separately excited generator. The voltage regulator regulates the output of 1 10V, the constant DC winding resistance is very small, and the instantaneous starting current is very large, which can generate enough torque on the shaft to start the diesel engine. When the diesel engine is started, the traction converter consists of rectifier and traction inverter. The traction inverter adopts 3000A/4500VGTO devices.
(3) The traction inverter power module composed of traction converter adopts a half-bridge circuit, which consists of two GTO switching elements on the upper and lower arms, a triangular absorption circuit and an anti-parallel diode. The traction inverter control cabinet and cooling system (except heat exchanger) are all placed in an electrical cabinet.
(4) The traction motor locomotive adopts D 120 AC traction motor with rated power of 50kW, rated voltage of 1288V, rated current of 280A, maximum current of 386A, rated speed of 889r/min and maximum speed of 3546r/min. The cooling mode is strong chase cooling, and the ventilation of each traction motor is 88m2/min.
(5) The locomotive with resistance braking device adopts two groups of horizontal braking resistance units installed on the mounting frame, and the two groups of resistance braking are respectively connected with the intermediate DC circuit through two new wave branches, with rated power of 2× 1900kW and rated voltage of 2600 V. The ventilator is driven by DC motor, and its power supply is provided by the brake resistor tap.
4. Auxiliary electrical system
The auxiliary circuit of DF8BJ diesel locomotive includes control circuits such as starting generator power generation circuit, battery charging circuit, fixed power generation circuit, car body ventilator circuit and air compressor starting circuit. The control circuit includes locomotive power supply circuit, diesel engine starting circuit, locomotive control circuit and protection circuit of control circuit, lighting circuit and signal lamp circuit, driving safety circuit, EFI control circuit and preheating boiler control circuit.
5. Microcomputer network control system
By controlling the excitation current of the excitation system, the microcomputer excitation regulator of DF8BJ diesel locomotive makes the current, voltage and power output by the traction generator within the specified range, and makes the diesel engine run with constant power together with the EFI system. It can control the current of the traction generator, make it have the best growth rate, and make the locomotive have good traction start and acceleration performance.
6. Body
The car body of DF8BJ diesel locomotive includes two parts: car body steel structure and car body equipment. The car body is supported by truss-type side walls, and its steel structure is mainly composed of all-steel welded structure in which the two ends of the car body, side walls, top and partition walls are welded into a whole, as well as lower underframe, lower end frame, obstacle sweeper and traction buffer device. The main load-bearing member is Q345C low alloy steel, and the vertical load of the car body is borne by the frame and side walls. The main bearing rod is a box coupler with TB/T 1595 standard for diesel and electric locomotives, and the buffer is MT-3. 7. Bogie The running part of DF8BJ diesel locomotive is two interchangeable three-axle bogies, with no centerless disk, no guide frame and tie rod axle box for positioning. Bogies are mainly composed of frame, wheelsets, axle boxes, side bearings, traction devices, motor suspension and basic braking devices. Axle box is a rolling bearing axle box, which is positioned by elastic pull rod. The primary suspension of the bogie consists of springs on both sides of the axle box and shock absorbers installed at the end of the axle box. The bogie secondary suspension device consists of four rubber side bearings of each bogie, which supports the overall mass of the upper part of the locomotive. The traction device of the steering wheel is a four-bar mechanism, which connects the bogie and the car body and transmits the speed traction and braking force. The traction motor adopts shaft suspension, one end of the motor is suspended on the axle through bearings, and the other end is suspended on the bogie frame through elastic suspenders. The locomotive foundation braking device adopts a set of single-sided single-tile pavement braking device for each wheel, and has an original automatic regulator in the tile room.
8. Brake system
The air system of DF8BJ diesel locomotive consists of two parts: an air braking device and an axle air assisting device. The air brake device consists of locomotive air source system and JZ-7 air brake. JZ-7 air brake is mainly composed of automatic brake valve, independent brake valve, equalizing air cylinder, relay valve, overfilling air cylinder, distribution valve, function reading, steering reading, dust filter check valve and emergency brake reading. There are two NPT5 air compressors for air supply.
9. Diesel engine
DF8BJ diesel locomotive is equipped with 16V2802ZJG diesel engine. The diesel engine block is of casting structure, with V-shaped cylinder arrangement, 50 included angle, four stroke, electronic fuel injection, direct injection combustion chamber, exhaust gas turbocharging, and intermediate cooling of pressurized air. It adopts high-strength forged steel crankshaft, parallel connecting rod, cylinder diameter of 280mm, piston stroke of 285mm, number of cylinders 16, and rated speed 1000/min. The calibrated power auxiliary system includes fuel system, lubricating oil, cooling water, preheating, air filtration system and 4200kW traction motor ventilation system. The fuel system with a load power of 4000kW consists of diesel engine fuel system and locomotive fuel system except diesel engine, which is set to provide fuel for diesel engine and preheat boiler. The locomotive fuel system consists of fuel tank, fuel filter screen, fuel delivery pump, fuel preheater, safety valve, check valve and stop valve, instruments and accessories. The diesel fuel system includes fuel filter, low-pressure fuel pipe, fuel injection, high-pressure fuel pipe, injector, electronic control injection system, pressure limiting valve, fuel injection pump and fuel injector return pipe system. The system is equipped with two parallel fuel delivery images, which can work simultaneously or independently. The primary fuel filter is RC-40W screen packing type. The oil transfer pump is an external gear oil pump driven by DC motor. The fuel preheater adopts oil-water heat exchange mode, and uses hot water for cooling diesel engine to heat fuel, so as to ensure the atomization quality of fuel. The lubricating oil system consists of locomotive lubricating oil system and diesel engine lubricating oil system, forming a complete lubricating oil circulation system. The locomotive lubricating oil system is mainly composed of lubricating oil filter, lubricating oil heat exchanger, starting lubricating oil pump, valves, pipelines and instruments to ensure that clean lubricating oil with certain pressure, temperature and capacity is provided to the diesel engine. The lubricating oil system of diesel engine consists of diesel oil pan, main lubricating oil pump, lubricating oil filter, lubricating oil heat exchanger, lubricating oil fine filter, lubricating cooling place and pipeline. The cooling water system is divided into two cooling systems: high temperature and low temperature. The main components are expansion water tank, cooling water pump, air cooler (intercooler), lubricating oil heat exchanger, radiator, cooling fan, hydrostatic oil heat exchanger, check valve and pipeline. The high temperature water system directly cools the parts in direct contact with gas, such as cylinder liner, cylinder head and turbocharger turbine outlet shell; The low-temperature water system cools the lubricating oil through the lubricating oil heat exchanger and the pressurized air through the air cooler (intercooler). Radiators are made of copper bars, which are V-shaped and installed on the steel skeleton of the cooling room, with a total of 54 groups. The high and low temperature cooling water systems each have a fan, and the high and low temperature cooling water pumps are centrifugal. The preheating system consists of spiral tube preheating boiler, fuel pump unit, water pump unit, blower unit, oil injection ignition device and electronic control equipment. The air filtration system is a four-stage filtration, and the first stage is a sand screen, which mainly filters out high-quality impurities in the air. The second stage is an inertial air filter; The third stage is the paper fine filter; The fourth stage is aluminum mesh filtration. The filter elements are respectively installed in the housings of the filters. Two sets of air filtering devices are respectively installed on the left and right side walls of the locomotive power room to filter the intake air of the front and rear superchargers. Traction motor ventilation system * * * is equipped with two blowers for traction motor ventilation, which are forward blade centrifugal fans. It is driven by diesel engine through the output shafts of front and rear gear boxes and nylon rope, which ventilates the three traction motors of the front and rear bogies of the locomotive.