Hybrid power supply control method suitable for low-speed shunting locomotives

Abstract

The present invention relates to the field of shunting control technology, and specifically to a hybrid power supply control method suitable for low-speed shunting locomotives, comprising the following steps: setting a preset level one and a preset level two of a power battery; when the handle level is less than or equal to the preset level one, the diesel engine is not started, and the power battery is used for power supply; when the handle level is greater than the preset level one and less than or equal to the preset level two, the maximum discharge power and maximum discharge time of the bidirectional DC-DC are calculated according to the current locomotive temperature to determine whether to start the diesel engine; when the handle level is greater than the preset level two, the diesel engine is started, and the diesel engine and the power battery are used for hybrid power supply. The hybrid power supply control method suitable for low-speed shunting locomotives provided by the present invention can avoid starting the diesel engine when the handle level is greater than the preset level one as in the prior art, thereby reducing the number of starts of the diesel engine and ensuring the service life of the diesel engine.

Description

Technical Field

[0001] The present invention relates to the technical field of shunting control, and in particular to a hybrid power supply control method suitable for a low-speed shunting locomotive. Background Art

[0002] Shunting locomotives are the basic power for shunting various locomotives, mining vehicles, freight cars, etc. Since it is necessary to start, pull or push the train set within a short distance, it does not require a high construction speed, but requires a certain amount of traction. It is characterized by frequent forward or reverse movement, and frequent starting and stopping. The vehicle uses power batteries and diesel engine grid-connected control to jointly power the vehicle.

[0003] There are two main methods for grid-connected control of existing power batteries and diesel engines:

[0004] The first is that when the operation position signal is 1, the driver controller handle level determines whether to start the diesel engine. When the handle level is low, the locomotive is only powered by the power battery. When the handle level is high, the locomotive automatically starts the diesel engine and connects to the power battery to provide energy for the locomotive. When the operation position signal is 0 and the handle level signal is ≥1, the locomotive is running in battery traction, and the diesel engine is started and stopped according to the SOC value. In this method, when the battery SOC value is sufficient, the locomotive will not start the diesel engine. At this time, the maximum output power of the locomotive is only the output power of the power battery, and the power of the whole vehicle is limited, which cannot meet the needs of high-power traction of the locomotive.

[0005] The second is to collect the handle level, battery SOC value and current locomotive speed information when the locomotive is running. When the SOC value of the power battery is greater than the preset SOC value and the handle level is below the preset level, the diesel engine will not be started; when the SOC value of the power battery is greater than the preset SOC value and the handle level is greater than the preset level, whether to start the diesel engine is determined according to the current locomotive speed; when the diesel engine charges the power battery, the amount of charge charged by the diesel engine to the power battery is determined according to the current locomotive speed. Since the constant torque part of the shunting locomotive is small, the constant power range is large, and the acceleration time is very fast, it is not very necessary to collect the vehicle speed as a judgment condition.

[0006] In addition, in the above two methods, the diesel engine is started many times, which affects the service life of the diesel engine. Summary of the invention

[0007] In order to overcome the technical defects of the existing power battery and diesel engine grid-connected control method on shunting locomotives, such as limited vehicle power, poor necessity of power supply judgment and frequent diesel engine starting, the present invention provides a hybrid power supply control method suitable for low-speed shunting locomotives.

[0008] The hybrid power supply control method applicable to a low-speed shunting locomotive provided by the present invention comprises the following steps:

[0009] A power battery that is charged and discharged in a bidirectional DC-DC manner is selected, and a preset level 1 and a preset level 2 of the power battery are set, wherein the preset level 1 is a maximum level that can be satisfied by the power battery through bidirectional DC-DC long-time discharge, and the preset level 2 is a maximum level that can be satisfied by the power battery through bidirectional DC-DC short-time discharge;

[0010] When the SOC value of the power battery is greater than the preset SOC value, and the handle level is less than or equal to the preset level 1, the diesel engine is not started, and the power battery is used for power supply;

[0011] When the SOC value of the power battery is greater than the preset SOC value, and the handle level is greater than the preset level one and less than or equal to the preset level two, the maximum discharge power and maximum discharge time of the bidirectional DC-DC are calculated according to the current locomotive temperature. If the maximum discharge power and maximum discharge time can meet the operating conditions, the diesel engine is not started. If the maximum discharge power and maximum discharge time cannot meet the operating conditions, the diesel engine is started, and the diesel engine and the power battery are mixed for power supply;

[0012] When the SOC value of the power battery is greater than the preset SOC value, and the handle level is greater than the preset level 2, the diesel engine is started, and the diesel engine and the power battery are mixed for power supply;

[0013] When the SOC value of the power battery is less than a preset SOC value, the power battery is charged.

[0014] Optionally, the power battery is a lithium battery.

[0015] Optionally, the preset level 2 is the maximum level that the power battery can meet through bidirectional DC-DC discharge for 5 minutes to 30 minutes.

[0016] Optionally, when the diesel engine and the power battery are mixed for power supply, if the handle level is lowered, the power battery stops discharging and the diesel engine alone is used for power supply.

[0017] The technical solution provided by the present invention has the following advantages compared with the prior art:

[0018] In the hybrid power supply control method of the present invention, the power battery is provided with a preset level 1 and a preset level 2, the preset level 1 is the maximum level that can be satisfied by long-time discharge, the preset level 2 is the maximum level that can be satisfied by short-time discharge, and the power provided by the preset level 2 is greater than the power of the preset level 1. Because the start and stop of the shunting locomotive are relatively frequent, if the locomotive operating conditions can be satisfied at the preset level 2, it can be avoided that the diesel engine is started when the power is greater than the preset level 1 as in the prior art, thereby reducing the number of diesel engine starts and ensuring the service life of the diesel engine. In addition, when the power required by the locomotive is large, the control method can start the diesel engine hybrid power supply to ensure the power demand of the whole vehicle; the control method judges the power supply mode based on the temperature of the locomotive, and the necessity of power supply judgment is strong; the control method adopts hybrid power supply, which can reduce exhaust emissions and noise pollution, and achieve the purpose of energy saving and emission reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0021] Figure 1 It is a block diagram of a hybrid power supply control method applicable to a low-speed shunting locomotive according to an embodiment of the present invention. DETAILED DESCRIPTION

[0022] In order to more clearly understand the above-mentioned objectives, features and advantages of the present invention, the scheme of the present invention will be further described below. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0023] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present invention, rather than all of the embodiments.

[0024] In one embodiment, Figure 1As shown, the hybrid power supply control method suitable for low-speed shunting locomotives includes the following steps: selecting a power battery that is charged and discharged in a bidirectional DC-DC manner, setting a preset level 1 and a preset level 2 of the power battery, wherein the preset level 1 is the maximum level that the power battery can meet through bidirectional DC-DC long-term discharge, and the preset level 2 is the maximum level that the power battery can meet through bidirectional DC-DC short-term discharge; when the SOC value of the power battery is greater than the preset SOC value, and the handle level is less than or equal to the preset level 1, the diesel engine is not started, and the power battery is used for power supply; when the SOC value of the power battery is greater than the preset SOC value, and the handle level is less than or equal to the preset level 1, the diesel engine is not started, and the power battery is used for power supply; When the handle level is greater than the preset level one and less than or equal to the preset level two, the maximum discharge power and maximum discharge time of the bidirectional DC-DC are calculated according to the current locomotive temperature. If the maximum discharge power and maximum discharge time can meet the operating conditions, the diesel engine will not be started. If the maximum discharge power and maximum discharge time cannot meet the operating conditions, the diesel engine will be started, and the diesel engine and the power battery will be mixed for power supply; when the SOC value of the power battery is greater than the preset SOC value and the handle level is greater than the preset level two, the diesel engine will be started, and the diesel engine and the power battery will be mixed for power supply; when the SOC value of the power battery is less than the preset SOC value, the power battery will be charged.

[0025] It should be noted that this embodiment is limited to a system using a bidirectional DCDC method for charging and discharging the power battery. The power battery is discharged to the intermediate DC bus through the bidirectional DCDC, and shares the bus with the DC power rectified by the diesel engine-main generator. When the power battery is charged, the diesel engine-main generator can be rectified and supplied to the intermediate DC bus, and the power battery is charged after conversion through the bidirectional DCDC.

[0026] Specifically, the preset level 2 is the maximum level that the power battery can meet through bidirectional DC-DC discharge for 5 minutes to 30 minutes, depending on different working conditions and the capacity of the DC-DC unit. This mode is also called high power mode.

[0027] Specifically, the power battery is a lithium battery. Of course, as an alternative implementation, the power battery can also be a supercapacitor or other power battery that is charged and discharged in a DC-DC manner.

[0028] Specifically, the power battery can be charged by the diesel engine-main generator rectifying and supplying the intermediate DC bus, and then charging the power battery after bidirectional DC-DC conversion; it can also be powered by the charging socket in the depot or other hybrid energy sources to supply the intermediate DC bus, and then charging the power battery after bidirectional DC-DC conversion.

[0029] In the hybrid power supply control method of this embodiment, the power battery is provided with preset level 1 and preset level 2, the preset level 1 is the maximum level that can be satisfied by long-time discharge, the preset level 2 is the maximum level that can be satisfied by short-time discharge, and the power provided by the preset level 2 is greater than the power of the preset level 1. Because the start and stop of the shunting locomotive are relatively frequent, if the locomotive operating conditions can be met at the preset level 2, it can be avoided that the diesel engine is started when it is greater than the preset level 1 as in the prior art, thereby reducing the number of diesel engine starts and ensuring the service life of the diesel engine. In addition, when the power required by the locomotive is large, the control method can start the diesel engine for hybrid power supply, thereby ensuring the power demand of the whole vehicle; the control method judges the power supply mode based on the temperature of the locomotive, and the necessity of power supply judgment is strong.

[0030] In some embodiments, when the diesel engine and the power battery are mixed for power supply, if the handle level is lowered, the power battery stops discharging and the diesel engine alone supplies power. In this way, compared with the solution of stopping the diesel engine and starting the power battery when the handle level is lowered, the number of starts and stops of the diesel engine is further reduced, thereby ensuring the service life of the diesel engine.

[0031] The above description is only a specific embodiment of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments described herein, but should conform to the widest scope consistent with the principles and novel features invented herein.

Claims

1. A hybrid power supply control method suitable for low-speed shunting locomotives, It is characterized in that The steps include: A power battery that is charged and discharged in a bidirectional DC-DC manner is selected, and a preset level 1 and a preset level 2 of the power battery are set, wherein the preset level 1 is a maximum level that can be satisfied by the power battery through bidirectional DC-DC long-time discharge, and the preset level 2 is a maximum level that can be satisfied by the power battery through bidirectional DC-DC short-time discharge; When the SOC value of the power battery is greater than the preset SOC value, and the handle level is less than or equal to the preset level 1, the diesel engine is not started, and the power battery is used for power supply; When the SOC value of the power battery is greater than the preset SOC value, and the handle level is greater than the preset level one and less than or equal to the preset level two, the maximum discharge power and maximum discharge time of the bidirectional DC-DC are calculated according to the current locomotive temperature. If the maximum discharge power and maximum discharge time can meet the operating conditions, the diesel engine is not started. If the maximum discharge power and maximum discharge time cannot meet the operating conditions, the diesel engine is started, and the diesel engine and the power battery are mixed for power supply; When the SOC value of the power battery is greater than the preset SOC value, and the handle level is greater than the preset level 2, the diesel engine is started, and the diesel engine and the power battery are mixed for power supply; When the SOC value of the power battery is less than a preset SOC value, the power battery is charged.

2. The hybrid power supply control method applicable to a low-speed shunting locomotive according to claim 1, It is characterized in that The power battery is a lithium battery.

3. The hybrid power supply control method applicable to a low-speed shunting locomotive according to claim 1, It is characterized in that The preset level 2 is the maximum level that the power battery can meet through bidirectional DC-DC discharge for 5 minutes to 30 minutes.

4. The hybrid power supply control method applicable to a low-speed shunting locomotive according to claim 1, It is characterized in that When the diesel engine and the power battery are used for mixed power supply, if the handle level is lowered, the power battery stops discharging and the diesel engine alone supplies power.

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