A traction drive system for a dc hybrid locomotive

Abstract

The application discloses a traction transmission system of a direct-current hybrid locomotive, which comprises a hybrid power source composed of an internal combustion generator set and a power battery, a diesel engine drives a main generator to generate three-phase alternating current, the three-phase alternating current is rectified by rectifier diodes, and then is connected in parallel with the power battery through a bidirectional DC / DC module to realize voltage increase and decrease, and the direct-current hybrid locomotive direct-current traction motor is driven by the three-phase alternating current; wherein, the internal combustion generator set comprises the diesel engine and the main generator which are connected in sequence. The application realizes energy saving and emission reduction of the locomotive, reduces the operation cost of the locomotive, and improves the precise control of the locomotive.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of rail transit, in particular to a traction transmission system of a DC hybrid locomotive. BACKGROUND

[0002] At present, the related technology of AC diesel hybrid locomotive has become mature, but there is no DC diesel hybrid locomotive. With the development of new energy, energy saving is in great demand. Many currently used DC diesel locomotives are facing elimination. Adding a power battery system to these locomotives can make them provide power alone or in combination with diesel power, so as to achieve the purpose of energy saving and emission reduction, and make them become pure electric locomotives or hybrid locomotives that meet the demand.

[0003] At present, the voltage of the traction motor of the DC locomotive changes with the speed of the locomotive in the traction working condition, and the voltage change amplitude is large. At the same time, it is limited by the installation space and cost of the DC locomotive. Therefore, there is currently no DC hybrid locomotive technology. If the power battery is only connected in parallel with the DC locomotive traction system, the problem that the power battery cannot be put into use in the full speed range of the locomotive exists. At the same time, there is a problem that the traction power control of the locomotive is not accurate. SUMMARY

[0004] In view of this, the present application provides a traction transmission system of a DC hybrid locomotive, which overcomes the key technology of transforming a DC diesel locomotive into a DC hybrid locomotive. The diesel power and the power battery power are mixed to provide power for the DC locomotive, and the problem of accurate control of the traction power of the hybrid DC locomotive is solved.

[0005] The present application discloses a traction transmission system of a DC hybrid locomotive, which comprises a hybrid power source composed of a diesel generator set and a power battery. The diesel engine drives the main generator to generate three-phase alternating current, which is rectified by the rectifier diode and connected in parallel with the power battery through the bidirectional DC / DC module after being boosted or stepped down, to jointly drive the DC traction motor of the DC hybrid locomotive. The diesel generator set comprises a diesel engine and a main generator connected in sequence.

[0006] Further, the power battery is connected in parallel with the DC hybrid locomotive DC power supply loop rectified by the diesel generator set after being controlled by the bidirectional DC / DC module, after passing through the positive fuse, the first disconnector, the positive contactor and the filter inductor in sequence; or the power battery is connected in parallel with the DC hybrid locomotive DC power supply loop rectified by the diesel generator set after being controlled by the bidirectional DC / DC module, after passing through the negative fuse, the negative contactor and the second disconnector in sequence; the DC power supply loop comprises a traction motor input contactor, a traction motor and a first contact of a working condition switch connected in sequence; the traction motor input contactor is connected with the self-load switch and the first contact of the working condition switch through the braking resistance unit respectively;

[0007] the first contact of the working condition switch is connected with the inductance or the second contact of the working condition switch or the second contact of the direction switch; the inductance is connected with the second contact of the working condition switch;

[0008] Meanwhile, the locomotive microcomputer system and the battery management system control respectively by collecting the current and voltage of the power battery; the locomotive microcomputer system, the battery management system and the bidirectional DC / DC module adopt CAN bus communication to realize the control of the hybrid of the locomotive diesel generator set and the power battery and the precise control of the locomotive traction power.

[0009] Further, in the traction working condition, the locomotive microcomputer system controls the traction motor to be put into use by closing the traction motor input contactor, placing the first contact of the working condition switch in the traction position and placing the first contact of the direction switch in the corresponding position, i.e. forward or backward; in the resistance braking working condition, the locomotive microcomputer system controls the traction motor to consume energy through the braking resistance unit by closing the traction motor input contactor and placing the first contact of the working condition switch in the electric braking position.

[0010] Further, when the power battery is put into use, the locomotive microcomputer system controls the pre-charging contactor to be closed, determines whether to start using the positive contactor according to the voltage signal collected by the voltage sensor, determines whether to start using the negative contactor according to the signal of the grounding insulation detection device and the self-checking condition of the battery system, determines the traction power requirement of the locomotive according to the signal of the driver controller and performs traction power distribution on the diesel generator set and the power battery to determine the mixing ratio of the two.

[0011] Further, the power control of the locomotive microcomputer system on the power battery is performed by the following way: after comparing the charge and discharge current value allowed by the battery management system with the charge and discharge current value required by the direct current hybrid locomotive, the target charge and discharge current value is transmitted to the bidirectional DC / DC module; at the same time, the size of the charge and discharge current of the power battery detected by the current sensor is transmitted to the bidirectional DC / DC module in real time, so that the bidirectional DC / DC module can realize closed-loop control of the charge and discharge current of the power battery; the power control of the locomotive microcomputer system on the diesel generator set is realized by controlling the excitation of the main generator.

[0012] Further, when the power of the power battery is sufficient, the power battery is connected in parallel with the main generator to supply power to the traction motor after rectification by the bidirectional DC / DC module; when the power of the power battery is insufficient, the main generator supplies power to the traction motor after rectification, and at the same time, the power battery is charged through the bidirectional DC / DC module.

[0013] Further, in the traction working condition, the voltage of the three-phase alternating current output by the main generator of the DC hybrid locomotive rises synchronously with the speed of the locomotive, and the amplitude span is large, so the bidirectional DC / DC module needs to follow the voltage of the main generator to adjust the voltage, so as to mix the output of the main generator and the power battery energy to supply power.

[0014] Further, in the power battery charging working condition, there are two charging modes, i.e., charging during locomotive running and manual charging during parking; when charging during locomotive running, the input voltage of the bidirectional DC / DC module is DC200V-DC980V, and the output voltage is DC570V-DC745V, and considering the module size, economy and battery charging current, the maximum current output from the single bidirectional DC / DC module to the power battery side is limited to 500A.

[0015] Further, when the output voltage of the main generator is lower than the voltage of the power battery, the circuit of the bidirectional DC / DC module works in the step-down mode.

[0016] Further, when the output voltage of the main generator is higher than the voltage of the power battery, the circuit of the bidirectional DC / DC module works in the step-up mode.

[0017] Due to the adoption of the above technical solutions, the application has the following advantages: the function of mixing the power battery power and the internal combustion power to provide power for the power is realized in the whole speed range of the locomotive, and in this process, the precise control of the traction power of the hybrid locomotive is realized, the energy saving and emission reduction are realized, and the locomotive operation cost is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments description. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art according to these drawings.

[0019] Figure 1 It is a schematic diagram of the traction transmission system of a DC hybrid locomotive. DETAILED DESCRIPTION

[0020] The application will be further described in combination with the drawings and embodiments, and the described embodiments are only some of the embodiments of the application, but not all the embodiments. All other embodiments obtained by those skilled in the art should belong to the protection scope of the embodiments of the application.

[0021] Reference Figure 1The application provides an embodiment of a traction transmission system of a direct current hybrid locomotive, which comprises a hybrid power source composed of an internal combustion generator set and a power battery, a diesel engine drives a main generator to generate three-phase alternating current, which is rectified by a rectifier diode and then connected in parallel with the power battery through a bidirectional DC / DC module for voltage boost or drop, to jointly drive a direct current traction motor of the direct current hybrid locomotive; wherein the internal combustion generator set comprises a diesel engine and a main generator connected in sequence; the power battery unit can be used as a power unit or an energy storage unit.

[0022] The power battery is connected in parallel with a direct current power supply loop of the direct current hybrid locomotive rectified by the internal combustion generator set through a bidirectional DC / DC module control after passing through a positive fuse, a first disconnecting switch, a positive contactor and a filter inductor in sequence; or the power battery is connected in parallel with the direct current power supply loop of the direct current hybrid locomotive rectified by the internal combustion generator set through a bidirectional DC / DC module control after passing through a negative fuse, a negative contactor and a second disconnecting switch in sequence; the direct current power supply loop comprises a traction motor input contactor, a traction motor and a first contact of a working condition switch connected in sequence; the traction motor input contactor is connected with a self-load switch and the first contact of the working condition switch through a braking resistance unit respectively;

[0023] The first contact of the working condition switch is connected with an inductor or a second contact of the working condition switch or a second contact of a direction switch; the inductor is connected with the second contact of the working condition switch;

[0024] Meanwhile, a locomotive microcomputer system and a battery management system control respectively by collecting current and voltage values of the power battery; the locomotive microcomputer system, the battery management system and the bidirectional DC / DC module adopt CAN bus communication to realize control of the internal combustion generator set and the power battery of the locomotive and precise control of traction power of the locomotive.

[0025] In the traction working condition, the locomotive microcomputer system controls the traction motor input contactor (1C) to be closed, the first contact (HKG) of the working condition switch is placed in the traction position, and the first contact (HKG) of the direction switch is placed in the corresponding position, i.e. forward or backward, so that the locomotive traction motor is put into use; in the resistance braking working condition, the locomotive microcomputer system controls the traction motor input contactor to be closed, and the first contact of the working condition switch is placed in the electric braking position, so that the energy on the traction motor is consumed through the braking resistance unit (1RZ).

[0026] When the power battery is put into use, the pre-charging contactor (4C) is closed under the control of the locomotive microcomputer system, and the locomotive microcomputer system determines whether to start using the positive contactor (2C) according to the voltage signal collected by the voltage sensor. The battery management system determines whether to start using the negative contactor (3C) according to the signal of the ground insulation detection device and the self-checking condition of the battery system. At the same time, the locomotive microcomputer system determines the traction power requirement of the locomotive according to the signal of the driver controller, and performs traction power distribution for the diesel generator set and the power battery to determine the mixing ratio of the two.

[0027] The power control of the power battery by the locomotive microcomputer system is as follows: after comparing the charge-discharge current value allowed by the battery management system with the charge-discharge current value required by the DC hybrid locomotive, the target charge-discharge current value is transmitted to the bidirectional DC / DC module; at the same time, the size of the power battery charge-discharge current detected by the current sensor (1SC) is transmitted to the bidirectional DC / DC module in real time, so that the bidirectional DC / DC module can realize closed-loop control of the power battery charge-discharge current. The power control of the diesel generator set by the locomotive microcomputer system is realized by controlling the excitation of the main generator.

[0028] When the power battery has sufficient energy, the power battery is connected in parallel with the main generator rectification to supply power to the traction motor through the bidirectional DC / DC module; when the power battery has insufficient energy, the main generator rectification supplies power to the traction motor, and the power battery is charged through the bidirectional DC / DC module.

[0029] In the traction working condition, the voltage of the three-phase alternating current output by the main generator of the DC hybrid locomotive rises synchronously with the rise of the locomotive speed, and the amplitude span is large, so the bidirectional DC / DC module needs to follow the voltage of the main generator rectification to adjust the voltage, so as to mix the output of the main generator with the energy of the power battery for power supply.

[0030] In the power battery charging working condition, there are two modes of charging during locomotive running and manual charging when the locomotive is parked. When charging during locomotive running, the input voltage of the bidirectional DC / DC module is DC200V-DC980V, and the output voltage is DC570V-DC745V. Considering the module size, economy and battery charging current, the maximum current output from a single bidirectional DC / DC module to the power battery side is limited to 500A.

[0031] When the output voltage of the main generator is lower than the voltage of the power battery, the circuit of the bidirectional DC / DC module works in the step-down mode.

[0032] When the output voltage of the main generator is higher than the voltage of the power battery, the circuit of the bidirectional DC / DC module works in the step-up mode.

[0033] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application but not to limit it. Although the present application has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that the specific embodiments of the present application can be modified or replaced equivalently without departing from the spirit and scope of the present application, and any modification or equivalent replacement without departing from the spirit and scope of the present application should be covered in the protection scope of the claims of the present application.

Claims

1. A traction drive system for a DC hybrid locomotive, characterized by, The hybrid power source is composed of an internal combustion generator set and a power battery, three-phase alternating current is generated by a diesel engine, rectified by a rectifier diode, and then connected in parallel with the power battery through a bidirectional DC / DC module after being boosted or reduced in voltage, to drive a direct current hybrid locomotive direct current traction motor together; wherein the internal combustion generator set comprises a diesel engine and a main generator connected in sequence; The power battery is connected in parallel with the rectified direct current hybrid locomotive direct current power supply loop of the internal combustion generator set through a bidirectional DC / DC module control after passing through a positive fuse, a first disconnector, a positive contactor and a filter inductor in sequence; or the power battery is connected in parallel with the rectified direct current hybrid locomotive direct current power supply loop of the internal combustion generator set through a bidirectional DC / DC module control after passing through a negative fuse, a negative contactor and a second disconnector in sequence; the direct current power supply loop comprises a traction motor input contactor, a traction motor and a first contact of a working condition switch connected in sequence; the traction motor input contactor is connected with a self-load switch and the first contact of the working condition switch through a braking resistance unit respectively; The first contact of the working condition switch is connected with an inductor or a second contact of the working condition switch or a second contact of a direction switch; the inductor is connected with the second contact of the working condition switch; Meanwhile, the locomotive microcomputer system and the battery management system control respectively by collecting the current and voltage values of the power battery; the locomotive microcomputer system, the battery management system and the bidirectional DC / DC module adopt CAN bus communication to realize the control of the hybrid of the internal combustion generator set and the power battery in the locomotive and the precise control of the traction power of the locomotive.

2. The traction drive system of a DC hybrid locomotive of claim 1, wherein, In the traction working condition, the locomotive microcomputer system controls the traction motor input contactor to be closed, the first contact of the working condition switch is placed in the traction position, and the first contact of the direction switch is placed in the corresponding position, i.e. forward or backward, so that the locomotive traction motor is put into use; in the resistance braking working condition, the locomotive microcomputer system controls the traction motor input contactor to be closed, and the first contact of the working condition switch is placed in the electric braking position, so that the energy on the traction motor is consumed through the braking resistance unit.

3. The traction drive system of a DC hybrid locomotive of claim 1, wherein, When the power battery is put into use, the pre-charging contactor is closed by the locomotive microcomputer system, and whether to start using the positive contactor is determined by the voltage signal collected by the voltage sensor; whether to start using the negative contactor is determined by the battery management system according to the ground insulation detection device signal and the self-checking condition of the battery system; at the same time, the locomotive microcomputer system determines the locomotive traction power requirement according to the driver controller signal, and performs traction power distribution on the internal combustion generator set and the power battery to determine the mixing ratio of the two.

4. The traction drive system of a DC hybrid locomotive of claim 1, wherein, The power control of the locomotive microcomputer system to the power battery is achieved by comparing the charge-discharge current value allowed by the battery management system with the charge-discharge current value required by the DC hybrid locomotive, transmitting the charge-discharge target current value to the bidirectional DC / DC module, and simultaneously transmitting the charge-discharge current value of the power battery detected by the current sensor to the bidirectional DC / DC module in real time, so that the bidirectional DC / DC module can realize closed-loop control of the charge-discharge current of the power battery.

5. The traction drive system of a DC hybrid locomotive of claim 1, wherein, When the power battery has sufficient energy, the power battery is connected in parallel with the main generator rectifier through the bidirectional DC / DC module to supply power to the traction motor; when the power battery has insufficient energy, the main generator rectifier supplies power to the traction motor, and the power battery is charged through the bidirectional DC / DC module.

6. The traction drive system of a DC hybrid locomotive of claim 1, wherein, In the traction working condition, the voltage of the three-phase alternating current rectified by the DC hybrid locomotive main generator rises synchronously with the speed of the locomotive, and the amplitude span is large, so the bidirectional DC / DC module needs to adjust the voltage to follow the voltage of the main generator rectifier, so as to mix the power output by the main generator with the power of the power battery.

7. The traction drive system of a DC hybrid locomotive of claim 1, wherein, In the power battery charging working condition, there are two modes of charging during locomotive running and manual charging when the locomotive is parked; when charging during locomotive running, the input voltage of the bidirectional DC / DC module is DC200V-DC980V, and the output voltage is DC570V-DC745V; considering the module size, economy and battery charging current, the maximum current output by a single bidirectional DC / DC module to the power battery side is limited to 500A.

8. The traction drive system of a DC hybrid locomotive of claim 1, wherein, When the output voltage of the main generator is lower than the voltage of the power battery, the circuit of the bidirectional DC / DC module works in the step-down mode.

9. The traction drive system of a DC hybrid locomotive of claim 1, wherein, When the output voltage of the main generator is higher than the voltage of the power battery, the circuit of the bidirectional DC / DC module works in the step-up mode.

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