Method for controlling rotating speed of engine in hybrid motor train unit

Abstract

The invention discloses a method for controlling the rotating speed of an engine in a hybrid motor train unit. A power source of the hybrid motor train unit comprises the engine and a power battery. The control method for the engine rotating speed in the hybrid motor train unit comprises the steps that the cold and hot machine states of an engine are obtained; the maximum rotating speed limit value of the engine is determined according to the cold and hot machine state; judging whether the power battery is put into operation; and if not, the operation rotating speed of the engine is controlled according to the operation working condition and the maximum rotating speed limiting value of the hybrid motor train unit. According to the technical scheme, the hybrid power performance of the hybrid motor train unit can be brought into full play, and the operation reliability of the hybrid motor train unit is improved.

Description

Technical Field

[0001] This invention relates to the field of train technology, and in particular to a method for controlling engine speed in a hybrid EMU (Electric Multiple Unit). Background Technology

[0002] As hybrid technology gradually expands into the railway sector, the operation mode of hybrid electric multiple units (EMUs) is becoming increasingly clear. Limited by the current power density and energy density of lithium batteries, hybrid EMUs primarily utilize diesel engines, supplemented by batteries. In traditional diesel multiple units, the diesel engine speed corresponds one-to-one with the driver's control lever position. However, in hybrid EMUs, the diesel engine speed not only needs to match different operating conditions of the EMU, meet the power requirements of different traction modes and the mechanical characteristics of the diesel engine, but also needs to consider the charging and discharging characteristics of the battery to achieve deep hybridization and leverage the characteristics of hybrid power equipment. Therefore, multi-dimensional coupling control of the diesel engine speed based on the driver's control lever position signal, combined with the EMU's operating conditions, the diesel engine's status, the traction mode, and the battery's operating status, has become a pressing technical problem to be solved. Summary of the Invention

[0003] This invention provides a method for controlling engine speed in hybrid EMUs, which can improve the operational reliability of hybrid EMUs.

[0004] This invention provides a method for controlling engine speed in a hybrid EMU (Electric Multiple Unit), wherein the power source of the hybrid EMU includes an engine and a power battery; the method for controlling engine speed includes:

[0005] Obtain the engine's hot / cold state;

[0006] The maximum speed limit of the engine is determined based on the engine's hot / cold state;

[0007] Determine whether the power battery is in operation;

[0008] If not, the engine operating speed is controlled according to the operating conditions of the hybrid EMU and the maximum speed limit.

[0009] Optionally, the operating speed of the engine is controlled according to the operating conditions of the hybrid EMU and the maximum speed limit, including:

[0010] Determine whether the operating condition is any one of the high-pressure blocking condition, braking condition, or preload condition;

[0011] If not, the operating speed of the engine is controlled according to the required speed level;

[0012] Wherein, the operating speed is less than or equal to the maximum speed limit.

[0013] Optionally, the engine speed control method also includes:

[0014] If the operating condition is the high-pressure blockade condition, then control the engine to run at the first speed;

[0015] If the operating condition is the braking condition, then control the engine to run at the second speed;

[0016] If the operating condition is the preload condition, then the operating speed of the engine is controlled according to the first given level.

[0017] The second rotational speed is greater than the first rotational speed.

[0018] Optionally, if the power battery is put into operation, the operating speed of the engine is controlled according to the traction mode of the hybrid EMU.

[0019] Optionally, the operating speed of the engine is controlled according to the traction mode of the hybrid EMU, including:

[0020] If the traction mode is torque mode, then based on the first control mode, the operating speed of the engine is controlled according to the operating conditions of the hybrid EMU and the maximum speed limit.

[0021] If the traction mode is a speed mode, then based on the second control mode, the operating speed of the engine is controlled according to the operating conditions of the hybrid EMU and the maximum speed limit.

[0022] Optionally, based on the first control mode, the operating speed of the engine is controlled according to the operating conditions of the hybrid EMU and the maximum speed limit, including:

[0023] Determine whether the operating condition is any one of the following: high-pressure blocking condition, braking condition, preload condition, or coasting condition;

[0024] If not, the operating speed of the engine is controlled according to the charging and discharging state of the power battery.

[0025] Optionally, controlling the engine's operating speed based on the charging and discharging state of the power battery includes:

[0026] Determine whether the power battery is in a priority charging state;

[0027] If so, determine whether the required speed level is less than or equal to the preset level;

[0028] If so, the engine's operating speed is controlled according to the required speed level and the first set sum value.

[0029] Optionally, if the required speed level is greater than the preset level, the operating speed of the engine is controlled according to the sum of the required speed level and the second setting.

[0030] Wherein, the first set sum value is greater than the second set sum value.

[0031] Optionally, if the power battery is in a priority discharge state, the operating speed of the engine is controlled according to the required speed level.

[0032] Optionally, if the power battery is not in the priority charging state or the priority discharging state, the operating speed of the engine is controlled according to the required speed level and the third set sum value.

[0033] Optionally, the engine speed control method also includes:

[0034] If the operating condition is the high-pressure blocking condition, then control the engine to run at the third speed;

[0035] If the operating condition is the preload condition, then the operating speed of the engine is controlled according to the second given level.

[0036] If the operating condition is the braking condition, then the operating speed of the engine is controlled according to the charging and discharging state of the power battery;

[0037] If the operating condition is the coasting condition, the engine speed is controlled according to the charging and discharging state of the power battery.

[0038] Optionally, when the operating condition is the braking condition, the engine operating speed is controlled according to the charging and discharging state of the power battery, including:

[0039] Determine whether the power battery is in a priority charging state;

[0040] If so, then control the engine to operate at the fourth speed;

[0041] If not, then control the engine to run at the fifth speed;

[0042] The fourth rotational speed is greater than the third rotational speed and the fifth rotational speed.

[0043] Optionally, when the operating condition is the coasting condition, the engine operating speed is controlled according to the charging and discharging state of the power battery, including:

[0044] Determine whether the power battery is in a priority charging state;

[0045] If so, the operating speed of the engine is controlled according to the first speed level;

[0046] If not, the operating speed of the engine is controlled according to the second speed level;

[0047] Wherein, the first speed level is greater than the second speed level.

[0048] Optionally, based on the second control mode, the operating speed of the engine is controlled according to the operating conditions of the hybrid EMU and the maximum speed limit, including:

[0049] Determine whether the operating condition is any one of the following: high-pressure blocking condition, braking condition, preload condition, or coasting condition;

[0050] If not, the operating speed of the engine is controlled according to the charging and discharging state of the power battery.

[0051] Optionally, controlling the engine's operating speed based on the charging and discharging state of the power battery includes:

[0052] Determine whether the power battery is in a priority charging state;

[0053] If so, then control the engine to run at the sixth speed;

[0054] If not, the engine's operating speed is controlled based on the mapping relationship between power range and power level, according to the operating power.

[0055] Optionally, the engine speed control method also includes:

[0056] If the operating condition is the high-pressure blockade condition, then control the engine to run at the seventh speed;

[0057] If the operating condition is the braking condition, then the operating speed of the engine is controlled according to the charging and discharging state of the power battery;

[0058] If the operating condition is the preload condition or the coasting condition, the engine speed is controlled according to the charging and discharging state of the power battery.

[0059] Optionally, when the operating condition is the braking condition, the engine operating speed is controlled according to the charging and discharging state of the power battery, including:

[0060] Determine whether the power battery is in a priority charging state;

[0061] If so, then control the engine to run at the eighth speed;

[0062] If not, the engine operating speed is controlled according to the third speed level.

[0063] Optionally, when the operating condition is the preload condition or the coasting condition, the engine operating speed is controlled according to the charging and discharging state of the power battery, including:

[0064] Determine whether the power battery is in a priority charging state;

[0065] If so, the operating speed of the engine is controlled according to the fourth speed level;

[0066] If not, the operating speed of the engine is controlled according to the fifth speed level;

[0067] The fourth speed level is greater than the fifth speed level.

[0068] The technical solution provided by this invention obtains the engine's hot / cold state and determines the engine's maximum speed limit based on this state. When the power battery is not in operation, the engine's operating speed is controlled according to the operating conditions of the hybrid EMU, while the engine's operating speed is below the maximum speed limit. This ensures that the engine's operating speed matches the specific operating conditions, allowing for timely response and improving the operational reliability of the hybrid EMU. Attached Figure Description

[0069] Figure 1 This is a schematic diagram of the power structure of a hybrid EMU provided in an embodiment of the present invention;

[0070] Figure 2 A flowchart illustrating a method for controlling engine speed in a hybrid EMU (Electric Multiple Unit) according to an embodiment of the present invention;

[0071] Figure 3 A flowchart illustrating another method for controlling engine speed in a hybrid EMU provided in an embodiment of the present invention;

[0072] Figure 4 A flowchart illustrating another method for controlling engine speed in a hybrid EMU provided in this embodiment of the invention;

[0073] Figure 5 A flowchart illustrating another method for controlling engine speed provided in an embodiment of the present invention;

[0074] Figure 6 A flowchart of an engine speed control method provided in an embodiment of the present invention. Detailed Implementation

[0075] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0076] Figure 1 This is a schematic diagram of the power structure of a hybrid EMU provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the hybrid EMU and its power source include an engine 10 and a power battery 20. The engine 10 includes a diesel engine, etc. Both the engine 10 and the power battery 20 are electrically connected to the traction motor 30, allowing the traction motor 30 to receive electrical energy from the engine 10 and / or the power battery 20, and generate traction force under the action of electrical signals, thereby driving the hybrid EMU to move. When the engine 10 includes a diesel engine, the diesel engine burns combustibles to generate mechanical energy. The electrical energy converted from mechanical energy can be provided to the traction motor 30 on one hand, and can also be transmitted to the power battery 20 to charge the power battery 20 when its charge is low. In addition, under braking conditions, the mechanical energy generated by the traction motor 30 can also be converted into electrical energy and fed back to the power battery 20.

[0077] Figure 2 This is a flowchart illustrating a method for controlling engine speed in a hybrid multiple unit (MMU) according to an embodiment of the present invention. This method is applicable to real-time control of engine speed in a MMU and can be executed by the MMU itself. Figure 2 As shown, the engine speed control methods include:

[0078] S101. Obtain the engine's hot / cold status.

[0079] The cold and hot engine status includes cold engine status and hot engine status. The cold engine status can be further distinguished into specific cold engine levels based on the current temperature of the coolant. The classification method of cold and hot engine can be set according to actual needs.

[0080] Specifically, the hot / cold engine state can be determined by the temperature of the coolant in the engine. When the coolant temperature is higher than a first preset temperature, the engine is considered to be in a hot engine state. In this state, operating the engine at a higher speed will not cause wear to the internal components. When the coolant temperature is lower than the first preset temperature, the engine is considered to be in a first cold engine state; when it is lower than a second preset temperature, it is considered to be in a second cold engine state; when it is lower than a third preset temperature, it is considered to be in a third cold engine state; and when it is lower than a fourth preset temperature, it is considered to be in a fourth cold engine state. The first preset temperature is higher than the second preset temperature, the second preset temperature is higher than the third preset temperature, and the third preset temperature is higher than the fourth preset temperature. For example, the first preset temperature is 60°C, the second preset temperature is 50°C, the third preset temperature is 40°C, and the fourth preset temperature is 20°C. Other preset temperatures are also possible and are not specifically limited here.

[0081] S102. Determine the maximum speed limit of the engine based on its hot or cold state.

[0082] The maximum speed limit indicates the maximum speed at which the engine can operate.

[0083] Specifically, there is a mapping relationship between the engine's hot / cold state and the engine speed limit. This mapping relationship can be a chart or graph, and the engine speed limit corresponding to the current hot / cold state can be used as the currently determined maximum engine speed limit. For example, when the coolant temperature in the engine is greater than or equal to a first preset temperature (60°C), the engine is in a hot engine state, and the maximum engine speed limit is 1800 r / min. When the coolant temperature in the engine is less than the first preset temperature (60°C), the engine is in a first cold engine state, and the maximum engine speed limit is 1750 r / min. When the coolant temperature in the engine is less than a second preset temperature (50°C), the engine is in a second cold engine state, and the maximum engine speed limit is 1500 r / min. When the coolant temperature in the engine is less than a third preset temperature (40°C), the engine is in a third cold engine state, and the maximum engine speed limit is 1200 r / min. When the coolant temperature in the engine is less than a fourth preset temperature (20°C), the engine is in a fourth cold engine state, and the maximum engine speed limit is 600 r / min. In this way, by setting different maximum speed limits for the engine in different hot and cold engine states, the engine can operate at a lower speed when cold, thus avoiding engine failure.

[0084] S103. Determine whether the power battery is in operation; if not, proceed to S104.

[0085] Specifically, if the power battery is put into operation, the power source of the EMU will mainly rely on the power battery, ensuring the reliability of the EMU operation.

[0086] S104. Control the engine speed according to the operating conditions and maximum speed limit of the hybrid EMU.

[0087] The operating conditions of the hybrid EMU include high-voltage blocking conditions, braking conditions, and preloading conditions, which can be divided according to actual needs, and no specific limitation is made here.

[0088] Specifically, if the power battery is not in operation, the train's power source is solely the engine. In this case, the engine speed can be controlled based on the operating conditions of the hybrid train, provided the engine speed is below the maximum speed limit. If the operating condition is a high-voltage shutdown, it indicates that the power transmission between the train and the engine is cut off. In this situation, the engine can be controlled to run at a lower speed so that maintenance personnel can determine the fault based on the engine's operation. Alternatively, if the driver does not require power output but the vehicle is not shut down, the engine can be controlled to run at a lower speed so that it can be switched to a higher operating speed promptly after the high-voltage shutdown is lifted, avoiding damage to the engine caused by directly running from zero speed to a higher speed. If the operating condition is a braking condition, it indicates that the train needs to decelerate. The power generated by the train can be fed back to the engine. In this case, the engine can be controlled at a higher operating speed so that it can receive the power fed back from the train. If the hybrid EMU operates under a pre-load condition, it means the EMU is in a pre-start but not yet fully started state. In this case, the engine can be controlled to operate at a set speed, at which it can provide power to the EMU for operation. Thus, even when the power battery is not operational, this scheme can rationally control the engine speed according to the operating conditions, giving the EMU basic operational and redundancy capabilities, thereby improving the operational reliability of the hybrid EMU.

[0089] The technical solution of this invention obtains the engine's hot / cold state and determines the engine's maximum speed limit based on this state. When the power battery is not in operation, the engine's operating speed is controlled according to the hybrid train's operating conditions, while the engine's operating speed is below the maximum speed limit. This ensures that the engine's operating speed matches the specific operating conditions, allowing for timely response and improving the hybrid train's operational reliability.

[0090] Based on the above embodiments, this embodiment of the invention describes the control of engine operating speed according to the operating conditions and maximum speed limit of the hybrid EMU. Optionally, Figure 3A flowchart of another method for controlling engine speed in a hybrid EMU provided by an embodiment of the present invention is shown below. Figure 3 As shown, the engine speed control methods include:

[0091] S201. Obtain the engine's hot / cold status.

[0092] S202. Determine the maximum speed limit of the engine based on its hot or cold state.

[0093] S203. Determine whether the power battery is in operation; if not, proceed to S204.

[0094] S204. Determine whether the operating condition is any of the following: high-pressure blocking condition, braking condition, or preload condition; if not, proceed to S205; if yes, proceed to 206.

[0095] S205. Control the engine's operating speed according to the required speed level.

[0096] The operating speed is set to be less than or equal to the maximum speed limit. If the operating speed exceeds the maximum speed limit, it may wear down internal engine components, leading to engine malfunctions. Therefore, setting the operating speed to be less than or equal to the maximum speed limit improves engine operating safety.

[0097] Specifically, the required RPM level represents the RPM level currently desired by the driver, that is, the RPM level input by the driver through the control lever. The correspondence between RPM levels and RPMs is shown in Table 1 below. The RPM corresponding to the required RPM level can be used as the engine's operating RPM, and the engine can be operated at that operating RPM.

[0098] It should be noted that the train supply status in Table 1 includes both the supply-operated and non-operated states. The supply-operated state indicates that electrical equipment such as air conditioning, lighting, electric kettles, or control circuits on the train are in operation. The non-operated state indicates that these electrical equipment are not in operation, typically occurring during the time between the train's movement from the rolling stock to the originating station. Once the train has moved to a section of track beyond the originating station, it enters the supply-operated state to provide passengers with a comfortable riding space. When determining the operating speed based on the speed rating, the speed corresponding to the train's current supply status can be used as the operating speed. For example, if the demand speed rating is 1 and the current supply status is non-operated, then the engine operating speed is determined to be 1050 r / min. Furthermore, as shown in Table 1, for the same speed range, the speed corresponding to the train being in the non-supply-supply state is less than or equal to the speed corresponding to the train being in the supply-supply state. This ensures that when the train is in the supply-supply state, the engine has a higher operating speed to supply the electrical equipment in the train, thereby improving the power supply reliability of the electrical equipment.

[0099] Table 1

[0100]

[0101] S206. If the operating condition is high-pressure blocking condition, the engine is controlled to run at the first speed; if the operating condition is braking condition, the engine is controlled to run at the second speed; if the operating condition is preload condition, the engine operating speed is controlled according to the first given level.

[0102] The second rotational speed is greater than the first rotational speed. The first given level can be set according to actual needs. In an exemplary embodiment, the first rotational speed is 600 r / min, the second rotational speed is 1300 r / min, and the first given level T1=1. It can also be other values, which are not specifically limited here.

[0103] Specifically, if the hybrid EMU operates under a high-pressure shutdown condition, it means the power transmission between the EMU and the engine is cut off. In this case, the engine can be controlled to run at a first speed so that maintenance personnel can determine the fault based on the engine's operating status. Alternatively, if the driver does not need power output but the vehicle is not shut down, the engine can be controlled to run at a first speed so that it can switch to a higher operating speed in time after the high-pressure shutdown is lifted, avoiding damage to the engine caused by running directly from zero speed to a higher speed. If the hybrid EMU operates under a braking condition, it means the EMU needs to decelerate. The power from the EMU can be fed back to the engine. In this case, the engine can be controlled at a second speed so that it can receive the power fed back from the EMU. If the hybrid EMU operates under a pre-loading condition, it means the hybrid EMU is in a pre-start but not yet fully started state. In this case, the engine can be controlled to run at the speed corresponding to the first given level so that the engine can provide pre-start power to the EMU to enable the EMU to run.

[0104] The technical solution provided by this invention, when the power battery is not in operation, adjusts the engine speed according to the operating conditions of the hybrid EMU. If the operating condition is a high-voltage blocking condition, the engine is controlled to run at a first speed; if the operating condition is a braking condition, the engine is controlled to run at a second speed; if the operating condition is a pre-loading condition, the engine speed is controlled according to a first given level. Thus, this solution can reasonably control the engine speed according to the operating conditions when the power battery is not in operation, enabling the EMU to have basic operating capabilities and redundancy, thereby improving the operational reliability of the hybrid EMU.

[0105] In an optional embodiment, if the power battery is in operation, the engine speed is controlled according to the traction mode of the hybrid EMU.

[0106] The traction mode includes torque mode and speed mode. When the vehicle is in torque mode, the engine speed is input by the driver's control lever, allowing the driver to precisely control the vehicle's operation. When the vehicle is in speed mode, the driver presets the speed, and the vehicle's control system automatically controls the engine speed based on the set speed.

[0107] Based on the above embodiments, this invention describes the operation of a power battery. Optionally, Figure 4 A flowchart illustrating another method for controlling engine speed in a hybrid EMU provided by an embodiment of the present invention is shown below. Figure 4 As shown, the engine speed control methods include:

[0108] S301, Obtain the engine's hot / cold status.

[0109] S302. Determine the maximum speed limit of the engine based on its hot or cold state.

[0110] S303. Determine whether the power battery is in operation; if not, proceed to S304; if yes, proceed to 305.

[0111] S304. Control the engine speed according to the operating conditions and maximum speed limit of the hybrid EMU.

[0112] S305. If the traction mode is torque mode, the engine operating speed is controlled based on the first control mode, according to the operating conditions and maximum speed limit of the hybrid EMU; if the traction mode is speed mode, the engine operating speed is controlled based on the second control mode, according to the operating conditions and maximum speed limit of the hybrid EMU.

[0113] Specifically, when the traction mode is torque mode, the driver's driving needs need to be taken into account. In this case, the engine speed can be controlled based on the first control mode and the current operating conditions. When the traction mode is speed mode, after the driver sets the travel speed, the train itself controls the engine speed based on the first control mode and the current operating conditions to ensure that the train runs stably at the set travel speed.

[0114] The technical solution of this invention improves the driver's experience by employing different speed control modes under different traction modes. When the traction mode is torque mode, based on a first control mode, the engine's operating speed is controlled according to the operating conditions of the hybrid EMU, taking into account the required speed from the driver's control handle. This ensures that the vehicle's output speed is close to or equal to the required speed, improving the driver's control reliability. When the traction mode is speed mode, based on a second control mode, the engine's operating speed is controlled according to the operating conditions of the hybrid EMU, allowing the train to adjust its operating speed in real time according to the operating conditions. This ensures the train's speed reaches the driver's set speed, reducing driver operations and improving the driver's experience.

[0115] Based on the above embodiments, this embodiment of the invention describes the control of engine operating speed according to the operating conditions and maximum speed limit of the hybrid EMU based on the first control mode. Figure 5 A flowchart of another engine speed control method provided in an embodiment of the present invention is shown below. Figure 5 As shown, the engine speed control method includes:

[0116] S401. Determine whether the operating condition is any of the following: high-pressure blocking condition, braking condition, preload condition, or coasting condition; if not, proceed to S402; if yes, proceed to S409.

[0117] S402. Determine whether the power battery is in a priority charging state; if yes, proceed to S403; if no, proceed to S406.

[0118] When the power battery is in a priority charging state, it indicates that the power battery has a low charge level and needs to be replenished in time.

[0119] Specifically, if the operating condition is not any of the high-voltage blocking condition, braking condition, pre-loading condition, or coasting condition, then the operating condition is considered normal operation. Under normal operation, the train travels at a constant speed or accelerating. The charging / discharging state of the power battery can be determined based on its remaining charge. If the current remaining charge of the power battery is less than a second preset charge, the power battery is determined to be in a priority charging state; if the current remaining charge of the power battery is greater than or equal to the second preset charge, the power battery is determined to exit the priority charging state. The second preset charge can be set according to actual needs; for example, the second preset charge is 15%, but it can also be other values, which are not specifically limited here.

[0120] S403. Determine whether the required speed level is less than or equal to the preset level; if yes, execute S404; if no, execute S405.

[0121] The preset level can be set according to actual needs. For example, if the speed level includes level 0 to level 16, the preset level can be 7, or other levels. No specific limitation is made here.

[0122] S404. Control the engine's operating speed according to the required speed level and the first set sum value.

[0123] The first set sum value can be a fixed value or a non-fixed value, and can be set according to actual needs. In an exemplary embodiment, the first set sum value is 4, but it can also be other values, which are not specifically limited here.

[0124] Specifically, when the required speed level is less than or equal to the preset level, it means that the engine operating speed can be increased based on the required speed level. That is, the sum of the required speed level and the first preset value is used as the control level, and the speed corresponding to the control level is used as the engine operating speed. This allows the electric energy generated by the engine to meet driving needs while also charging the power battery.

[0125] S405: Control the engine's operating speed according to the required speed level and the sum of the second setting.

[0126] Wherein, the first set sum value is greater than the second set sum value. The second set sum value can be a fixed value or a non-fixed value, and can be set according to actual needs. In an exemplary embodiment, the second set sum value is 3, but it can also be other values, which are not specifically limited here.

[0127] Specifically, when the required speed level is greater than the preset level, it indicates that the engine currently requires a relatively high speed. In this case, increasing the engine's operating speed by too much based on the required speed level would cause the engine's operating speed to exceed the maximum speed limit. Therefore, the sum of the required speed levels at the second preset value is used as the control level, and the speed corresponding to the control level is used as the engine's operating speed. This allows the electrical energy generated by the engine to meet driving needs while also charging the power battery.

[0128] It should be noted that if the sum of the second set value for the required speed level exceeds the engine's maximum speed level, then the speed corresponding to the maximum speed level will be used as the control speed.

[0129] S406. Determine whether the power battery is in a priority discharge state; if yes, proceed to S407; if no, proceed to S408.

[0130] When the power battery is in a priority discharge state, it means that the power battery has a high charge level and needs to release the charge in time so that the power battery can store the energy when the power energy is transferred to the power battery, thus avoiding energy waste.

[0131] Specifically, the charging and discharging state of the power battery can be determined based on its remaining charge. If the current remaining charge of the power battery is greater than a first preset charge, the power battery is determined to be in a priority discharge state; if the current remaining charge of the power battery is less than or equal to the first preset charge, the power battery is determined to exit the priority discharge state. The first preset charge can be set according to actual needs; for example, the first preset charge is 95%, but it can also be other values, which are not specifically limited here.

[0132] S407. Control the engine's operating speed according to the required speed level.

[0133] Specifically, if the power battery is in a priority discharge state, the engine does not need to provide excess power to the power battery. In this case, the speed corresponding to the required speed level can be used as the engine's operating speed to meet the driver's driving needs.

[0134] S408: Control the engine's operating speed according to the required speed level and the third set sum value.

[0135] The third set sum value can be a fixed value or a non-fixed value, and can be set according to actual needs. In an exemplary embodiment, the third set sum value is 1, but it can also be other values, which are not specifically limited here.

[0136] Specifically, if the power battery is neither in a priority discharge state nor a priority charging state, it means that the power battery can both discharge externally and store externally supplied electrical energy. In this case, the sum of the required speed level and the third set sum value can be used as the control level, and the speed corresponding to the control level can be used as the engine's operating speed. This satisfies the driver's driving needs while allowing excess electrical energy generated by the engine to be supplied to the power battery. The excess electrical energy is related to the magnitude of the third set sum value. By setting a third set sum value with a smaller value, overcharging of the power battery can be avoided, keeping the power battery stably in a chargeable and dischargeable state and improving the operational stability of the power battery.

[0137] S409. If the operating condition is high-voltage blocking, the engine is controlled to run at the third speed. If the operating condition is preload, the engine speed is controlled according to the second given level. If the operating condition is braking, the engine speed is controlled according to the charging and discharging state of the power battery. If the operating condition is coasting, the engine speed is controlled according to the charging and discharging state of the power battery.

[0138] The third rotational speed and the second given level can be fixed or non-fixed values, and can be set according to actual needs. In an exemplary embodiment, the third rotational speed is 600 r / min and the second given level is 1, but other values ​​are not specifically limited here.

[0139] Specifically, if the hybrid EMU operates under a high-pressure shutdown condition, it means that the power transmission between the EMU and the engine is cut off. In this case, the engine can be controlled to run at a third speed so that maintenance personnel can determine the fault based on the engine's operating status. Alternatively, if the driver does not require power output but the vehicle is not shut down, the engine can be controlled to run at a third speed so that after the high-pressure shutdown is lifted, the engine can be switched to a higher operating speed in a timely manner, avoiding damage to the engine caused by running directly from zero speed to a higher speed. If the hybrid EMU operates under a pre-load condition, it means that the hybrid EMU is in a pre-start state and has not yet fully started. In this case, according to the second given level, the engine can be controlled to run at the speed corresponding to the second given level so that the engine can provide pre-start power to the EMU to enable the EMU to run. If the hybrid EMU operates under braking or coasting conditions, it means that the EMU needs to decelerate or does not require power output. The power generated by the EMU can be fed back to the engine. At this time, the engine speed can be controlled according to the charging and discharging status of the power battery so that the engine can receive the power fed back by the EMU and convert it into electrical energy to charge the power battery, thereby improving the electrical energy stability of the power battery and thus improving the operational stability of the hybrid EMU.

[0140] The technical solution provided by this invention, based on the operation of the power battery and the torque mode of traction, adjusts the engine speed according to the operating conditions of the hybrid EMU. Thus, when the power battery is in operation, this solution can rationally control the engine speed according to the operating conditions and the charging / discharging state of the power battery. This ensures that the engine speed meets the driver's driving needs while also providing power to the power battery under appropriate conditions, improving the power battery's energy stability and thereby enhancing the operational reliability of the hybrid EMU.

[0141] Optionally, when the operating condition is braking, the engine speed is controlled according to the charging and discharging state of the power battery, including: determining whether the power battery is in a priority charging state; if so, controlling the engine to run at a fourth speed; if not, controlling the engine to run at a fifth speed.

[0142] The fourth rotational speed is greater than the third and fifth rotational speeds. In an exemplary embodiment, the third and fifth rotational speeds are both 600 r / min, and the fourth rotational speed is 1430 r / min. Other speeds are also possible, and no specific limitation is made here.

[0143] Specifically, when the power battery is in priority charging mode, it indicates that the battery charge is low and needs to be replenished promptly. In this case, the engine can be controlled to operate at the fourth speed, allowing the electrical energy generated by the engine to charge the power battery. When the power battery is not in priority charging mode, it indicates that the battery charge is moderate or high, and there is no need to charge it. In this case, the engine can be controlled to operate at the fifth speed, allowing the engine to maintain a lower operating speed so that when the required speed increases later, the engine speed can be quickly increased, improving operational reliability.

[0144] Optionally, when the operating condition is coasting, the engine speed is controlled according to the charging and discharging state of the power battery, including: determining whether the power battery is in a priority charging state; if so, controlling the engine speed according to a first speed level; if not, controlling the engine speed according to a second speed level.

[0145] The first speed level is greater than the second speed level. In an exemplary embodiment, the first speed level is 4 and the second speed level is 0, but other speed levels are also possible, and no specific limitation is made here.

[0146] Specifically, when the train is in coasting mode, it means that the train does not require additional power and moves under its own inertia. In coasting mode, if the power battery is in priority charging mode, it means that the battery charge is low and needs to be replenished promptly. At this time, the speed corresponding to the first speed level can be used as the engine's operating speed, allowing the electrical energy generated by the engine to charge the power battery. When the power battery is not in priority charging mode, it means that the battery charge is moderate or high, and there is no need to charge it. At this time, the speed corresponding to the second speed level can be used as the engine's operating speed, allowing the engine to maintain a lower operating speed so that when the required speed increases later, the engine speed can be quickly increased, improving operational reliability.

[0147] It should be noted that when the speed corresponding to the speed level is taken as the engine's operating speed, the correspondence between the speed level and the speed can be referred to Table 2 below.

[0148] Table 2

[0149]

[0150] Based on the above embodiments, this embodiment of the invention describes the control of engine operating speed according to the operating conditions and maximum speed limit of the hybrid EMU based on the second control mode. Figure 6 A flowchart of an engine speed control method provided in an embodiment of the present invention is shown below. Figure 6 As shown, the engine speed control method includes:

[0151] S501. Determine whether the operating condition is any of the following: high-pressure blocking condition, braking condition, preload condition, or coasting condition; if not, execute S502; if yes, execute S505.

[0152] S502. Determine whether the power battery is in a priority charging state; if yes, proceed to S503; if no, proceed to S504.

[0153] When the power battery is in a priority charging state, it indicates that the power battery has a low charge level and needs to be replenished in time.

[0154] Specifically, if the operating condition is not any of the high-voltage blocking condition, braking condition, pre-loading condition, or coasting condition, then the operating condition is considered normal operation. Under normal operation, the train travels at a constant speed or accelerating. The charging / discharging state of the power battery can be determined based on its remaining charge. If the current remaining charge of the power battery is less than a second preset charge, the power battery is determined to be in a priority charging state; if the current remaining charge of the power battery is greater than or equal to the second preset charge, the power battery is determined to exit the priority charging state. The second preset charge can be set according to actual needs; for example, the second preset charge is 15%, but it can also be other values, which are not specifically limited here.

[0155] S503, control the engine to run at the sixth speed.

[0156] The sixth speed setting can be the maximum permissible speed of the engine and can be set according to actual needs. For example, the sixth speed setting is 1800 r / min, but it can also be other speeds; no specific limitation is made here.

[0157] Specifically, when the power battery is in a priority charging state, the engine is controlled to run at a higher sixth speed, so that the engine can provide more electrical energy for the train set to use, and the excess electrical energy can charge the power battery.

[0158] S504. Based on the mapping relationship between power range and power level, the engine operating speed is controlled according to the operating power.

[0159] The mapping relationship between power range and power level can be found in Table 3 below, but other mappings are not specified here.

[0160] Specifically, operating power represents the power output of the train during current operation. Different road conditions and other factors result in varying operating power. Since the speed required by the driver in speed mode is a fixed value, the varying operating power ensures that the hybrid EMU can operate at the designated speed. When the operating power falls within a certain power range, the corresponding power level is designated as the power level, and each power level corresponds to a speed level. The speed corresponding to each speed level is then used as the engine's operating speed. For example, the power levels include 17 levels from P0 to P16, and there are 6 power ranges: the first power range is 0-85%×P5, the second power range is 60%×P6-85%×P7, the third power range is 60%×P8-85%×P9, the fourth power range is 60%×P10-85%×P11, the fifth power range is 60%×P12-85%×P13, and the sixth power range is 60%×P14-85%×P16. When the operating power is less than 85%×P5, the corresponding power level is P5, so that the engine can quickly and stably operate at the power level P5 to meet the vehicle's operational stability. When the operating power is less than 60%, it means that the current power requirement of the hybrid EMU has not yet reached P6. At this time, the engine is still operated at the power level P5, so that the engine's operating power increases slowly and steadily, avoiding sudden power changes that may affect the passenger's riding experience and improving the vehicle's driving smoothness. In this way, by dividing the power into multiple power ranges, there is no need to frequently adjust the engine speed, allowing the engine to drive the hybrid train smoothly and stably, improving the driving stability and reliability of the hybrid train, and enhancing the riding experience for drivers and passengers.

[0161] Table 3

[0162]

[0163] S505. If the operating condition is high-voltage blocking, the engine is controlled to run at the seventh speed. If the operating condition is braking, the engine speed is controlled according to the charging and discharging state of the power battery. If the operating condition is preload or coasting, the engine speed is controlled according to the charging and discharging state of the power battery.

[0164] The seventh rotational speed can be a fixed value or a non-fixed value, and can be set according to actual needs. In an exemplary embodiment, the seventh rotational speed is 600 r / min, but it can also be other values, which are not specifically limited here.

[0165] Specifically, if the hybrid EMU operates under high-voltage shutdown conditions, it means the power transmission between the EMU and the engine is cut off. In this case, the engine can be controlled to run at its seventh speed so that maintenance personnel can determine the fault based on the engine's operating status. Alternatively, if the driver does not need power output but the vehicle is not shut down, the engine can be controlled to run at its seventh speed so that it can switch to a higher operating speed promptly after the high-voltage shutdown is lifted, avoiding damage to the engine caused by running directly from zero speed to a higher speed. If the hybrid EMU operates under braking conditions, it means the EMU needs to decelerate. The power generated by the EMU can be fed back to the engine. In this case, the engine's operating speed can be controlled according to the charging and discharging status of the power battery so that the engine can receive the power fed back from the EMU and convert it into electrical energy to charge the power battery, improving the power battery's electrical energy stability and thus improving the operational stability of the hybrid EMU. If the operating condition of the hybrid EMU is pre-loaded, it means that the hybrid EMU is in a pre-start and not yet fully started state. If the operating condition of the hybrid EMU is coasting, it means that the hybrid EMU does not need power output at this time. At this time, the engine speed can be controlled according to the charging and discharging status of the power battery.

[0166] The technical solution provided by this invention, based on the operation of the power battery and the traction mode being speed mode, adjusts the engine speed accordingly according to the operating conditions of the hybrid EMU. Thus, when the power battery is in operation, this solution can rationally control the engine speed based on the operating conditions and the charging / discharging state of the power battery. This ensures that the engine speed meets the driver's set speed while also providing power to the power battery under appropriate operating conditions, improving the power battery's energy stability and thereby enhancing the operational reliability of the hybrid EMU.

[0167] Optionally, when the operating condition is braking, the engine speed is controlled according to the charging and discharging state of the power battery, including: determining whether the power battery is in a priority charging state; if so, controlling the engine to run at the eighth speed; if not, controlling the engine speed according to the third speed level.

[0168] The eighth and third speed levels can be fixed or variable, and can be set according to actual needs. In an exemplary embodiment, the eighth speed is the maximum allowable engine speed of 1800 r / min, and the third speed level is 1, but can also be other values, which are not specifically limited here.

[0169] Specifically, when the power battery is in priority charging mode, it indicates that the battery charge is low and needs to be replenished promptly. In this case, the engine can be controlled to operate at the eighth speed, allowing the electrical energy generated by the engine to charge the power battery. When the power battery is not in priority charging mode, it indicates that the battery charge is moderate or high, and charging is not required. In this case, the speed corresponding to the third speed level can be used as the engine's operating speed, allowing the engine to maintain a lower operating speed. This ensures that when the required speed increases later, the engine speed can be quickly increased, improving operational reliability. The speeds corresponding to the third speed level can be found in Table 1 or Table 2 above.

[0170] Optionally, when the operating condition is preloaded or coasting, the engine speed is controlled according to the charging and discharging state of the power battery, including: determining whether the power battery is in a priority charging state; if so, controlling the engine speed according to the fourth speed level; if not, controlling the engine speed according to the fifth speed level.

[0171] The fourth speed level is greater than the fifth speed level. In an exemplary embodiment, the fourth speed level is 4 and the fifth speed level is 0, but other speed levels are also possible and are not specifically limited here. The speeds corresponding to the fourth and fifth speed levels can be referred to Table 1 or Table 2 above.

[0172] Specifically, when the train is in preload or coasting mode, it indicates that the required power is low or zero. In coasting or preload mode, if the power battery is in priority charging mode, it means the battery charge is low and needs to be replenished promptly. In this case, the speed corresponding to the fourth speed level can be used as the engine's operating speed, allowing the electrical energy generated by the engine to charge the power battery. When the power battery is not in priority charging mode, it means the battery charge is moderate or high, and there is no need to charge it. In this case, the speed corresponding to the fifth speed level can be used as the engine's operating speed, allowing the engine to maintain a lower operating speed so that when the required speed increases later, the engine speed can be quickly increased, improving operational reliability.

[0173] The technical solution provided by this invention not only better adapts to different states of the hybrid EMU engine (diesel engine) and the power battery, but also formulates corresponding engine (diesel engine) speed control strategies based on the operating states of torque mode and speed mode to achieve different functions of the hybrid EMU. Furthermore, it limits the maximum speed of the engine (diesel engine) under different cold-start conditions, allowing the power battery to play a greater role in cold-start conditions, thereby limiting the engine (diesel engine) load and preventing engine (diesel engine) failure due to cold start. Controlling the diesel engine speed when the power battery is not engaged provides the EMU with basic operational and redundancy capabilities. When the power battery is engaged and the traction mode is torque mode, it can respond differently to various operating conditions of the EMU. When the traction mode is speed mode, the corresponding diesel engine speed level can be determined by the operating (entry-level) power of the EMU, assisting in the precise control of the diesel engine speed in speed mode.

[0174] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, combinations, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A method for controlling engine speed in a hybrid EMU, characterized in that, The power source of the hybrid EMU includes an engine and a power battery; the method for controlling the engine speed includes: Obtain the engine's hot / cold state; The maximum speed limit of the engine is determined based on the engine's hot / cold state; Determine whether the power battery is in operation; If not, the engine operating speed is controlled according to the operating conditions of the hybrid EMU and the maximum speed limit.

2. The engine speed control method according to claim 1, characterized in that, Based on the operating conditions of the hybrid EMU and the maximum speed limit, the operating speed of the engine is controlled, including: Determine whether the operating condition is any one of the high-pressure blocking condition, braking condition, or preload condition; If not, the operating speed of the engine is controlled according to the required speed level; Wherein, the operating speed is less than or equal to the maximum speed limit.

3. The engine speed control method according to claim 2, characterized in that, Also includes: If the operating condition is the high-pressure blockade condition, then control the engine to run at the first speed; If the operating condition is the braking condition, then control the engine to run at the second speed; If the operating condition is the preload condition, then the operating speed of the engine is controlled according to the first given level. The second rotational speed is greater than the first rotational speed.

4. The engine speed control method according to claim 1, characterized in that, If the power battery is put into operation, the operating speed of the engine is controlled according to the traction mode of the hybrid EMU.

5. The engine speed control method according to claim 4, characterized in that, Controlling the engine's operating speed according to the traction mode of the hybrid EMU includes: If the traction mode is torque mode, then based on the first control mode, the operating speed of the engine is controlled according to the operating conditions of the hybrid EMU and the maximum speed limit. If the traction mode is a speed mode, then based on the second control mode, the operating speed of the engine is controlled according to the operating conditions of the hybrid EMU and the maximum speed limit.

6. The engine speed control method according to claim 5, characterized in that, Based on the first control mode, according to the operating conditions of the hybrid EMU and the maximum speed limit, the operating speed of the engine is controlled, including: Determine whether the operating condition is any one of the following: high-pressure blocking condition, braking condition, preload condition, or coasting condition; If not, the operating speed of the engine is controlled according to the charging and discharging state of the power battery.

7. The engine speed control method according to claim 6, characterized in that, Controlling the engine's operating speed based on the charging and discharging state of the power battery includes: Determine whether the power battery is in a priority charging state; If so, determine whether the required speed level is less than or equal to the preset level; If so, the engine's operating speed is controlled according to the required speed level and the first set sum value.

8. The engine speed control method according to claim 7, characterized in that, If the required speed level is greater than the preset level, the engine operating speed is controlled according to the sum of the required speed level and the second preset value. Wherein, the first set sum value is greater than the second set sum value.

9. The engine speed control method according to claim 7, characterized in that, If the power battery is in a priority discharge state, the engine operating speed is controlled according to the required speed level.

10. The engine speed control method according to claim 9, characterized in that, If the power battery is not in the priority charging state or the priority discharging state, the operating speed of the engine is controlled according to the required speed level and the third set sum value.

11. The engine speed control method according to claim 6, characterized in that, Also includes: If the operating condition is the high-pressure blocking condition, then control the engine to run at the third speed; If the operating condition is the preload condition, then the operating speed of the engine is controlled according to the second given level. If the operating condition is the braking condition, then the operating speed of the engine is controlled according to the charging and discharging state of the power battery; If the operating condition is the coasting condition, the engine speed is controlled according to the charging and discharging state of the power battery.

12. The engine speed control method according to claim 11, characterized in that, When the operating condition is the braking condition, the engine speed is controlled according to the charging and discharging state of the power battery, including: Determine whether the power battery is in a priority charging state; If so, then control the engine to operate at the fourth speed; If not, then control the engine to run at the fifth speed; The fourth rotational speed is greater than the third rotational speed and the fifth rotational speed.

13. The engine speed control method according to claim 11, characterized in that, When the operating condition is the coasting condition, the engine speed is controlled according to the charging and discharging state of the power battery, including: Determine whether the power battery is in a priority charging state; If so, the operating speed of the engine is controlled according to the first speed level; If not, the operating speed of the engine is controlled according to the second speed level; Wherein, the first speed level is greater than the second speed level.

14. The engine speed control method according to claim 5, characterized in that, Based on the second control mode, according to the operating conditions of the hybrid EMU and the maximum speed limit, the operating speed of the engine is controlled, including: Determine whether the operating condition is any one of the following: high-pressure blocking condition, braking condition, preload condition, or coasting condition; If not, the operating speed of the engine is controlled according to the charging and discharging state of the power battery.

15. The engine speed control method according to claim 14, characterized in that, Controlling the engine's operating speed based on the charging and discharging state of the power battery includes: Determine whether the power battery is in a priority charging state; If so, then control the engine to run at the sixth speed; If not, the engine's operating speed is controlled based on the mapping relationship between power range and power level, according to the operating power.

16. The engine speed control method according to claim 14, characterized in that, Also includes: If the operating condition is the high-pressure blockade condition, then control the engine to run at the seventh speed; If the operating condition is the braking condition, then the operating speed of the engine is controlled according to the charging and discharging state of the power battery; If the operating condition is the preload condition or the coasting condition, the engine speed is controlled according to the charging and discharging state of the power battery.

17. The engine speed control method according to claim 16, characterized in that, When the operating condition is the braking condition, the engine speed is controlled according to the charging and discharging state of the power battery, including: Determine whether the power battery is in a priority charging state; If so, then control the engine to run at the eighth speed; If not, the engine operating speed is controlled according to the third speed level.

18. The engine speed control method according to claim 16, characterized in that, When the operating condition is the preload condition or the coasting condition, the engine operating speed is controlled according to the charging and discharging state of the power battery, including: Determine whether the power battery is in a priority charging state; If so, the operating speed of the engine is controlled according to the fourth speed level; If not, the operating speed of the engine is controlled according to the fifth speed level; The fourth speed level is greater than the fifth speed level.

Images