CN206487580U - Exchange diesel engine of diesel locomotive variable frequency starting circuit is realized based on four quadrant convertor - Google Patents

Abstract

The utility model relates to the technical field of electric transmission systems of diesel locomotives, in particular to a frequency conversion starting circuit for diesel engines of AC diesel locomotives based on a four-quadrant converter. link, the four-quadrant converter inverts the intermediate DC link voltage and outputs it to the main generator for starting; the four-quadrant converter, the 3-way chopper bridge arm in the traction converter module drives the traction motor to work 2, 3, 6 The 4th chopper bridge arm of the 1st traction converter module adjusts the voltage and current output to charge the power battery, and the 4th chopper bridge arm of the 1st, 4th, and 5th traction converter module adjusts the power consumption to the braking resistor; A smoothing reactor, a pre-charging resistor and a contactor are arranged between the power battery of the four-quadrant converter and the traction converter module. The utility model does not need to add conversion equipment such as a start-up switch CTS and a high-power contactor, and the high-voltage start-up of the power battery is faster and easier.

Description

Realization of frequency conversion starting circuit for AC diesel locomotive diesel engine based on four-quadrant converter

technical field

The utility model relates to the technical field of the electric transmission system of a diesel locomotive, in particular to a frequency conversion start circuit for an AC diesel locomotive diesel engine based on a four-quadrant converter.

Background technique

There are roughly three ways to start a diesel locomotive diesel engine: electric motor start, air motor start, and inverter frequency conversion start.

The electric motor is started, that is, the DC starter motor is driven by the control battery 74V or 110V DC, and the diesel engine is driven to rotate through the gearbox or the large disc until the diesel engine speed reaches the ignition speed, and the diesel engine is started. This method is simple and easy to implement, but there are many mechanical links, the service life of the motor is short, and the requirements for controlling the battery are high, so it is not suitable for the development direction of the integration of the main and auxiliary parts of the AC drive locomotive.

The air motor is started, that is, the compressed air is used to drive the air motor to run, and the diesel engine is driven to rotate through the driving mechanism until the speed of the diesel engine reaches the ignition speed, and the start of the diesel engine is completed. This method requires compressed air as power. When the total air cylinder pressure is insufficient, it is necessary to use a DC air compressor to work to supplement the compressed air. The real-time performance is poor, there are many mechanical links, and the motor and air cylinder are large in size, so it is not suitable for AC transmission locomotives. The development direction of the main and auxiliary integration.

The inverter starts with variable frequency, that is, the 74V or 110V DC voltage of the control battery is used to provide excitation during the start-up stage, and at the same time, the voltage of the control battery is loaded to the intermediate DC link, and the three-phase AC is output through the traction converter module, which is loaded to the output of the main generator At this time, the main generator is used as a motor, and the frequency conversion and voltage regulation of the traction converter module cooperates with the excitation controller to drive the main generator to rotate until the speed of the diesel engine reaches the ignition speed, and then disconnect the control of the traction converter module. The main generator is used as a generator. This method saves the complicated mechanical structure and reduces the volume, which is in line with the development direction of the integration of the main and auxiliary parts of the AC drive locomotive. The starting voltage of the control battery is low and it is not easy to start.

Utility model content

In order to overcome the deficiencies of the existing technology, the utility model provides a circuit based on a four-quadrant converter to realize the frequency conversion start of the diesel engine of an AC internal combustion locomotive.

The technical scheme that the utility model solves its technical problem adopts is:

A frequency conversion starting circuit for an AC diesel locomotive based on a four-quadrant converter, including a main generator, an excitation control circuit, a main converter cabinet, a power battery, and load equipment. The excitation control circuit includes an automatic excitation controller, an excitation transformer, And the control battery, the main converter cabinet includes a four-quadrant converter, several traction converter modules and auxiliary converter modules, and the load equipment includes several traction motors, a group of braking resistors and auxiliary transformers.

According to another embodiment of the present utility model, it further includes that the main generator is connected to one end of the contactor K1, the other end of K1 is connected to a four-quadrant converter and an excitation transformer, the excitation transformer is connected to an automatic excitation controller, and the automatic excitation controller is another One input end is connected to the control storage battery, and the output end of the automatic excitation controller is connected to the excitation input end of the main generator.

According to another embodiment of the present utility model, it further includes that the four-quadrant converter rectifies and outputs the three-phase AC power generated by the main generator to the intermediate DC link for the traction converter module and the auxiliary converter module to work, At the same time, the four-quadrant converter can invert and output the intermediate DC link voltage to the main generator for start-up.

According to another embodiment of the present utility model, it further includes that the 3-way chopper bridge arm in the traction converter module drives the traction motor to work, and the fourth chopper of the 2#, 3#, and 6# traction converter modules The wave bridge arm adjusts the voltage and current output to charge the power battery, and the fourth chopper bridge arm of the 1#, 4#, 5# traction converter module adjusts the power consumption to the braking resistor; the power battery and the traction transformer There are smoothing reactor L1, pre-charging resistor R1 and contactors K2, K3, K4 between the converter modules.

The beneficial effect of the utility model is that the start-up method realized by this circuit saves complicated mechanical structures, simplifies the complicated start-up circuit, does not need to increase conversion equipment such as a start-up transfer switch CTS and a high-power contactor, and reduces start-up supporting facilities , to facilitate the overall optimization of the space layout, and at the same time use the high-voltage power battery to start the machine more quickly and easily, which is also in line with the development direction of the main and auxiliary integration of AC transmission locomotives.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the utility model is further described.

Fig. 1 is a schematic circuit diagram of the utility model.

In the figure 1. main generator, 2. excitation control circuit, 21. automatic excitation controller, 22. excitation transformer, 23. control battery, 3. main converter cabinet, 31. four-quadrant converter, 32. traction transformer Converter module, 33, auxiliary converter module, 4, power battery, 5, load equipment, 51, traction motor, 52, braking resistor, 53, auxiliary transformer.

detailed description

As shown in Figure 1 is a structural schematic diagram of the utility model, a four-quadrant converter to realize AC diesel locomotive frequency conversion starting circuit, including the main generator 1, excitation control circuit 2, main converter cabinet 3, power battery 4, and The load equipment 5, the excitation control circuit 2 includes an automatic excitation controller 21, an excitation transformer 22, and a control battery 23, and the main converter cabinet 3 includes a four-quadrant converter 31, several traction converter modules 32 and auxiliary converters The load device 5 includes a plurality of traction motors 51 , a set of braking resistors 52 and an auxiliary transformer 53 . The main generator 1 is connected to one end of the contactor K1, and the other end of K1 is connected to the four-quadrant converter 31 and the excitation transformer 22. The excitation transformer 22 is connected to the automatic excitation controller 21, and the other input end of the automatic excitation controller 21 is connected to the control battery 23. The output end of the excitation controller 21 is connected to the excitation input end of the main generator 1 . The four-quadrant converter 31 rectifies the three-phase alternating current generated by the main generator 1 and outputs it to the intermediate DC link for the traction converter module 32 and the auxiliary converter module 33 to work. At the same time, the four-quadrant converter 31 can convert the intermediate DC The link voltage is inverted and output to the main generator 1 for starting up.

The 3-way chopper bridge arm in the traction converter module 32 drives the traction motor 51 to work, and the fourth chopper bridge arm of the 2#, 3#, and 6# traction converter modules adjusts the voltage and current output to charge the power battery, The fourth chopper arm of the 1#, 4#, 5# traction converter module 32 adjusts the power consumption to the braking resistor 52; a smoothing reactor is installed between the power battery 4 and the traction converter module 32 L1, pre-charging resistor R1 and contactors K2, K3, K4.

The main generator is connected to the output terminal of the diesel engine. After the diesel engine works normally, it drives the main generator to output three-phase AC voltage to provide the power source for the locomotive. The diesel engine rotates until the diesel engine reaches the ignition speed, completes the starting of the diesel engine, and then switches to the generator working condition.

The excitation control loop includes two parts, the automatic excitation controller 21 and the excitation transformer 22. The automatic excitation controller 21 has two power supply modes of AC input and DC input. The automatic excitation controller 21 can output frequency and voltage according to the preset main generator, The chopper controls the excitation current, and close-loop adjusts the output voltage of the main generator. Especially in the start-up phase, the excitation size is reasonably determined according to the diesel engine speed, so that the acceleration torque is optimal; in the start-up phase, the automatic excitation controller 21 uses the locomotive battery 23 for power supply; when the diesel engine start-up is completed, the three-phase AC output from the main generator 1 is stepped down by the excitation transformer 22 for use by the automatic excitation controller 21 .

It is the key of the utility model that the four-quadrant converter replaces the uncontrollable rectification module used by the original locomotive. In the start-up phase, the high voltage of the power battery 4 is input to the intermediate DC link, and the four-quadrant converter 31 inverts the DC link voltage and outputs it to the main generator 1, which drives the main generator 1 to rotate with frequency conversion, and at the same time communicates with the automatic excitation control 21 Inverter communication, reasonable calculation of inverter frequency; when the diesel engine is started, the four-quadrant converter 31 will switch to the rectification mode, and the three-phase alternating current generated by the main generator 1 will be rectified by the four-quadrant converter 31 and output to the DC link.

The utility model is provided with 6 traction converter modules 32 1#, #2#, 3#, 4#, 5#, 6# and 1 auxiliary converter module 7#. 6 traction converter modules 32 are used to drive 6 traction motors to work, to invert the voltage of the intermediate DC link into the required three-phase AC, and to drive the traction motors to work; at the same time, the 1#, 4#, 5# inverters The 4th bridge arm chopper adjusts the voltage, and outputs it to the braking resistor 52 to consume excess energy or quickly discharge; while the 4th bridge arm chopper adjusts the voltage of the 2#, 3#, 6# inverters, and outputs it to the power battery 4 for battery charging.

There is also an auxiliary converter module module 33 7#, which inverts the voltage of the intermediate DC link into the required three-phase AC, and drives the auxiliary converter 33 to work.

The power battery 4 is another power source of the hybrid locomotive, which provides energy to the locomotive when the diesel engine is not working. When working in the charging mode, first close the contactors K4 and K3, the traction converter module chops and outputs the voltage of the required voltage value, filters it through the smoothing reactor, limits the current through the pre-charging resistor, and pre-charges the power battery 4; When the charging current reaches the initial value, close the contactor K2 for fast charging. When working in the discharge mode, the contactors K2, K3 and K4 are closed, the traction converter module is directly turned on, and the voltage of the power battery 4 is directly output to the DC link for use by the load.

The control specific mode of the utility model circuit is as follows:

Close the contactor K1, close the contactors K3 and K4, close the delay contactor K2, enable the automatic excitation controller 21 to work in the start-up excitation mode, and the four-quadrant converter 31 to work in the inverter mode, cooperate with the automatic excitation controller 21. Drive the diesel engine to rotate;

After the start-up of the diesel engine is completed, the automatic excitation controller 21 is enabled to work in the normal working mode, and the four-quadrant converter 31 works in the rectification mode, and the start-up process is completed.

The start-up method realized by this circuit saves the complex mechanical structure, simplifies the complex start-up circuit, does not need to add conversion equipment such as start-up transfer switch CTS and high-power contactor, reduces start-up supporting facilities, and facilitates the overall optimization of space layout. The high-voltage start-up using the power battery will be faster and easier, and it is also in line with the development direction of the main and auxiliary integration of AC drive locomotives.

Claims (4)

1. A variable frequency starting circuit for an AC diesel locomotive based on a four-quadrant converter, characterized in that it includes a main generator (1), an excitation control circuit (2), a main converter cabinet (3), and a power battery (4 ), and load equipment (5), the excitation control loop (2) includes an automatic excitation controller (21), an excitation transformer (22), and a control battery (23), and the main converter cabinet (3) includes Four-quadrant converter (31), several traction converter modules (32) and auxiliary converter modules (33), the load equipment (5) includes several traction motors (51), a group of braking resistors (52 ) and auxiliary transformer (53). 2. The AC diesel locomotive variable frequency starting circuit based on a four-quadrant converter according to claim 1, characterized in that the main generator (1) is connected to one end of the contactor K1, and the other end of K1 is connected to a four-quadrant converter (31) and excitation transformer (22), the excitation transformer (22) is connected to the automatic excitation controller (21), the other input end of the automatic excitation controller (21) is connected to the control battery (23), and the automatic excitation controller (21) The output terminal is connected to the excitation input terminal of the main generator (1). 3. The four-quadrant converter based on the four-quadrant converter to realize the frequency conversion starting circuit of the diesel engine of the AC diesel locomotive, characterized in that, the four-quadrant converter (31) converts the three-phase AC power generated by the main generator (1) The rectified output is sent to the intermediate DC link for the traction converter module (32) and the auxiliary converter module (33) to work, while the four-quadrant converter (31) can invert and output the intermediate DC link voltage to the main generator ( 1) For boot use. 4. The frequency conversion start-up circuit for AC diesel locomotive diesel engine based on the four-quadrant converter according to claim 1, characterized in that, the traction motor (51 ) work, the 4th chopper bridge arm of the 2#, 3#, 6# traction converter module adjusts the voltage and current output to charge the power battery, and the 1#, 4#, 5# traction converter module (32 ) of the fourth chopper bridge arm to adjust the power consumption to the braking resistor (52); between the power battery (4) and the traction converter module (32) there is a smoothing reactor L1 and a pre-charging resistor R1 And contactors K2, K3, K4.