Vehicle energy management method and device

Abstract

The invention discloses a vehicle energy management method and device, and relates to the field of rail transit, and the method comprises the steps: determining a target power corresponding to a target traction force of a vehicle; the battery mode determines the output power of the storage battery according to the target power and the energy conversion efficiency; the diesel generator mode determines the output power of each diesel generator according to the target power and the energy conversion efficiency; and the mixed mode determines the output power of the storage battery and each diesel generator according to the target power, the electric quantity of the storage battery, the operation efficiency of the diesel generator and the energy conversion efficiency. The battery mode is independently powered by the storage battery, and the output power of the storage battery is directly calculated. The diesel generator mode balances the output power of the two diesel generators to meet the target power demand. The mixed mode is combined with factors such as battery electric quantity and operation efficiency of the diesel generators, the electric quantity of the storage battery and the working efficiency of the diesel generators are balanced, the output power of the storage battery and the two diesel generators is adjusted, and multi-power-source control is achieved.

Description

Technical Field

[0001] This invention relates to the field of rail transportation, and in particular to a method and apparatus for energy management of vehicles. Background Technology

[0002] In the rail transit sector, efficient coordination of power sources is crucial for improving vehicle performance. Currently, most rail transit vehicles on the market use a single diesel generator plus battery power system. To better meet the vehicle's power demands, a three-power-source system is often employed: two diesel generators and a traction battery. However, existing control schemes for single diesel generators plus batteries cannot directly address the matching issues of the three power sources in a dual-diesel generator scenario, and cannot achieve a reasonable distribution of power output to meet the vehicle's traction requirements. Summary of the Invention

[0003] The purpose of this invention is to provide a vehicle energy management method and device. In battery mode, the battery supplies power independently, and the output power of the battery is directly calculated. In diesel generator mode, the output power of the two diesel generators is balanced to meet the target power requirement. In hybrid mode, factors such as battery charge and diesel generator operating efficiency are considered to balance the battery charge and diesel generator efficiency, and adjust the output power of the battery and the two diesel generators, thus achieving control of multiple power sources.

[0004] To solve the above-mentioned technical problems, the present invention provides a vehicle energy management method, comprising:

[0005] Determine the target power corresponding to the vehicle's target traction force;

[0006] Determine the current operating mode of the power source, wherein the operating mode includes at least two of the following: battery mode, diesel generator mode, and hybrid mode;

[0007] When the operating mode is battery mode, the output power of the battery is determined based on the target power and energy conversion efficiency.

[0008] When the operating mode is diesel generator mode, the output power of each diesel generator is determined based on the target power and energy conversion efficiency;

[0009] When the operating mode is mixed mode, the output power of the battery and each diesel generator is determined based on the target power, the battery charge, the operating efficiency and energy conversion efficiency of the diesel generator.

[0010] On the other hand, the power source includes at least one diesel generator and a battery, and the vehicle also includes a traction converter and an auxiliary converter;

[0011] The output terminal of each of the diesel generators is connected to the input terminal of the traction converter. The output terminal of the traction converter and the output terminal of each of the batteries are connected to the input terminal of the auxiliary converter. The output terminal of the auxiliary converter is connected to the traction motor and the power supply load.

[0012] The traction converter is used to convert the AC power output by the diesel generator into DC power, and the auxiliary converter is used to convert the DC power output by the traction converter and the battery into AC power.

[0013] The process of determining the energy conversion efficiency includes:

[0014] Determine the energy conversion efficiency of the traction converter, the auxiliary converter, the diesel generator, and the battery.

[0015] On the other hand, determining the energy conversion efficiency of the auxiliary converter includes:

[0016] The power required for the auxiliary converter to convert AC to DC is determined based on its output power and efficiency. The expression for the power required for the auxiliary converter to convert AC to DC is as follows:

[0017] P_AuxOutputpower_Tcu'=P_AuxOutputpower_Tcu / η_AUX_inv;

[0018] Wherein, P_AuxOutputpower_Tcu' is the power required for the auxiliary converter to convert AC to DC, P_AuxOutputpower_Tcu is the output power of the auxiliary converter, and η_AUX_inv is the efficiency of the auxiliary converter.

[0019] On the other hand, determining the energy conversion efficiency of the diesel generator includes:

[0020] The power converted from the diesel generator's output power to the DC link is determined based on the diesel generator's output power, power generation efficiency, and converter efficiency. The expression for the power converted from the diesel generator's output power to the DC link is as follows:

[0021] P_Diesel_actual'=P_Diesel_actual×η_gen×η_gen-inv;

[0022] Where P_Diesel_actual' is the power converted from the output power of the diesel generator to the DC link, P_Diesel_actual is the output power of the diesel generator, η_gen is the power generation efficiency of the diesel generator, and η_gen-inv is the operating efficiency of the converter of the diesel generator.

[0023] On the other hand, determining the energy conversion efficiency of the battery includes:

[0024] The power converted from the battery discharge power to the DC link is determined based on the battery discharge power and the battery chopper efficiency. The expression for the power converted from the battery discharge power to the DC link is as follows:

[0025] P_actual_dischargePower'=P_actual_dischargePower×η_batt-inv;

[0026] Wherein, P_actual_dischargePower' is the power converted from the battery discharge power to the DC link, P_actual_dischargePower is the battery discharge power, and η_batt-inv is the chopper efficiency of the battery.

[0027] On the other hand, after determining the current operating mode of the power source, it also includes:

[0028] When the current operating mode is diesel generator mode or hybrid mode, the first diesel generator is started when the target power is greater than or equal to the first power;

[0029] When the current operating mode is diesel generator mode or hybrid mode, the first diesel generator that has been started will be shut down when the target power is less than or equal to the second power.

[0030] When the current operating mode is diesel generator mode or hybrid mode, the second diesel generator is started when the target power is greater than or equal to the third power;

[0031] When the current operating mode is diesel generator mode or hybrid mode, if the target power is less than or equal to the fourth power, the second diesel generator that has been started will be shut down.

[0032] The fourth power, the third power, the first power, and the second power decrease sequentially.

[0033] On the other hand, when the operating mode is battery mode, the output power of the battery is determined based on the target power and energy conversion efficiency, including:

[0034] When the remaining charge of the battery is greater than the first charge and the maximum discharge power is greater than 0, the output power of the battery is determined according to the target power and energy conversion efficiency. The expression for the output power of the battery is P_actual_dischargePower=P_DC_setpoint / η_batt-inv;

[0035] Wherein, P_actual_dischargePower is the discharge power of the battery, P_DC_setpoint is the target power of the DC link, and η_batt-inv is the chopper efficiency of the battery.

[0036] On the other hand, when the operating mode is diesel generator mode, the output power of each diesel generator is determined based on the target power and energy conversion efficiency, including:

[0037] The number of diesel generators is determined when the fuel level in the fuel tank of the diesel generator is higher than the minimum fuel level.

[0038] When a single diesel generator is operating, its output power is determined based on the target power and energy conversion efficiency. The expression for the output power of a single diesel generator is as follows:

[0039] P_Diesel_setpoint=(P_DC1_setpoint+P_DC2_setpoint) / (η_gen×η_gen-inv);

[0040] Wherein, P_Diesel_setpoint is the output power of a single diesel generator, P_DC1_setpoint is the target power of the first DC link, P_DC2_setpoint is the target power of the second DC link, η_gen is the power generation efficiency of the diesel generator, and η_gen-inv is the operating efficiency of the converter of the diesel generator.

[0041] When two diesel generators are running, the output power of each diesel generator is determined based on the target power and energy conversion efficiency. The expression for the output power of each diesel generator is as follows:

[0042] P_DieselX_setpoint=P_DCX_setpoint / (η_gen×η_gen-inv);

[0043] Where P_DieselX_setpoint is the output power of the Xth single diesel generator, and P_DCX_setpoint is the target power of the Xth DC link, X=1,2.

[0044] On the other hand, when the operating mode is a mixed mode, the output power of the battery and each of the diesel generators is determined based on the target power, the battery charge, the operating efficiency of the diesel generators, and the energy conversion efficiency, including:

[0045] The DC link is powered by a battery.

[0046] When the battery charge is less than a first charge level, start the diesel generator;

[0047] When the diesel generator is running as a single unit, if the target power is greater than the maximum output power of the diesel generator and the battery charge is greater than the first charge, the diesel generator is controlled to operate at the maximum output power, and the battery output power is the difference between the target power and the maximum output power.

[0048] When the diesel generator is running as a single unit, if the target power is less than the maximum output power of the diesel generator, greater than the optimal output power of the diesel generator, and the battery charge is less than the second charge, the diesel generator is controlled to operate at the optimal output power. The battery output power is the difference between the target power and the optimal output power, and the second charge is greater than the first charge.

[0049] When two diesel generators are running, the output power of each diesel generator is determined based on the target power and energy conversion efficiency. The expression for the output power of each diesel generator is as follows:

[0050] P_DieselX_setpoint=P_DCX_setpoint / (η_gen×η_gen-inv);

[0051] Where P_DieselX_setpoint is the output power of the Xth single diesel generator, and P_DCX_setpoint is the target power of the Xth DC link, X=1,2.

[0052] On the other hand, it also includes:

[0053] Set the target charging capacity for the battery;

[0054] Control the diesel generator to supply power to the storage battery;

[0055] When the battery reaches the target charging level, the diesel generator is controlled to stop supplying power to the battery.

[0056] To address the aforementioned technical problems, the present invention also provides a vehicle energy management device, comprising:

[0057] Memory, used to store computer programs;

[0058] A processor is used to implement the steps of the above-described vehicle energy management method when executing the computer program.

[0059] This application provides a vehicle energy management method and apparatus, relating to the field of rail transit, including determining the target power corresponding to the vehicle's target traction force; in battery mode, determining the battery's output power based on the target power and energy conversion efficiency; in diesel generator mode, determining the output power of each diesel generator based on the target power and energy conversion efficiency; and in hybrid mode, determining the output power of the battery and each diesel generator based on the target power, battery charge, diesel generator operating efficiency, and energy conversion efficiency. In battery mode, the battery supplies power independently, and the battery's output power is directly calculated. In diesel generator mode, the output power of the two diesel generators is balanced to meet the target power requirement. In hybrid mode, factors such as battery charge and diesel generator operating efficiency are considered to balance the battery charge and diesel generator efficiency, adjusting the output power of the battery and the two diesel generators, thus achieving control of multiple power sources. Attached Figure Description

[0060] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the prior art and embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0061] Figure 1 A flowchart of a vehicle energy management method provided by the present invention;

[0062] Figure 2 A schematic diagram of the structure of a vehicle power source provided by the present invention;

[0063] Figure 3 This is a schematic diagram of the structure of a vehicle energy management device provided by the present invention. Detailed Implementation

[0064] The core of this invention is to provide a vehicle energy management method and device. In battery mode, the battery provides power independently, and the output power of the battery is directly calculated. In diesel generator mode, the output power of the two diesel generators is balanced to meet the target power requirement. In hybrid mode, factors such as battery charge and diesel generator operating efficiency are considered to balance the battery charge and diesel generator efficiency, and adjust the output power of the battery and the two diesel generators, thus achieving control of multiple power sources.

[0065] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0066] Figure 1 A flowchart of a vehicle energy management method provided by the present invention, the vehicle energy management method comprising:

[0067] S11: Determine the target power corresponding to the target traction force of the vehicle;

[0068] The target traction force is calculated in the TCMS (Train Control and Management System) and transmitted to the TCU (Transmission Control Unit). During the traction calculation process, various efficiency parameters need to be considered, including traction motor efficiency (η_tractionmotor) and traction converter efficiency (η_tract_inv). These efficiency parameters are stored and retrieved in the TCMS in the form of lookup tables based on the operating conditions.

[0069] S12: Determine the current operating mode of the power source, which includes at least two of the following: battery mode, diesel generator mode, and hybrid mode;

[0070] To enhance the effectiveness of various control methods, the power source in this application includes multiple operating modes. In battery mode, only the battery supplies power to the traction motor; in diesel generator mode, only the diesel generator supplies power to the traction motor (it should be noted that there are generally two diesel generators); in hybrid mode, both the battery and the diesel generator supply power to the traction motor simultaneously.

[0071] S13: When the operating mode is battery mode, determine the output power of the battery based on the target power and energy conversion efficiency;

[0072] Specifically, in battery mode, the power output from the battery is not directly supplied to the traction motor. Instead, it needs to be converted from DC to AC by an inverter before it can power the traction motor. Therefore, controlling the traction motor with the target power cannot meet the motor's needs. Thus, energy conversion efficiency needs to be considered when calculating the battery's output power.

[0073] S14: When the operating mode is diesel generator mode, determine the output power of each diesel generator based on the target power and energy conversion efficiency;

[0074] Specifically, although only one diesel generator provides power in diesel generator mode, there are generally two diesel generators. Therefore, the power output coordination between the two diesel generators needs to be considered. Taking two traction motors as an example, there are two DC links. When using one diesel generator, it needs to meet the power supply requirements of both DC links. When using two diesel generators, each generator only needs to meet the power supply requirements of its corresponding DC link. Furthermore, since the power output of the diesel generator is not directly supplied to the traction motor, it needs to be converted from AC to DC by an inverter, and then back to AC before supplying power to the traction motor. Therefore, controlling the diesel generator with the target power alone cannot meet the needs of the traction motor. Thus, energy conversion efficiency needs to be considered when calculating the output power of the diesel generator.

[0075] S15: When the operating mode is mixed mode, the output power of the battery and each diesel generator is determined based on the target power, the battery charge, the operating efficiency of the diesel generator, and the energy conversion efficiency.

[0076] Similarly, when both the battery and the diesel generator are operating, it's necessary to consider that the diesel generator operates within its optimal power range, and the battery also needs to operate at its optimal charge level. Therefore, a balance between the two devices is required. One battery can be used in conjunction with one diesel generator, or one battery can be used in conjunction with two diesel generators. Therefore, the start-up time and number of diesel generators need to be determined based on the actual target power.

[0077] This application provides a vehicle energy management method relating to the rail transit field, including determining the target power corresponding to the vehicle's target traction force; in battery mode, determining the battery's output power based on the target power and energy conversion efficiency; in diesel generator mode, determining the output power of each diesel generator based on the target power and energy conversion efficiency; and in hybrid mode, determining the output power of both the battery and each diesel generator based on the target power, battery charge, diesel generator operating efficiency, and energy conversion efficiency. In battery mode, the battery provides power independently, and its output power is directly calculated. In diesel generator mode, the output power of the two diesel generators is balanced to meet the target power requirement. In hybrid mode, factors such as battery charge and diesel generator operating efficiency are considered to balance the battery charge and diesel generator efficiency, adjusting the output power of the battery and the two diesel generators, thus achieving multi-power source control.

[0078] Based on the above embodiments:

[0079] Figure 2 A schematic diagram of the structure of a vehicle power source provided by the present invention;

[0080] In some embodiments, the power source includes at least one diesel generator and a battery, and the vehicle also includes a traction converter and an auxiliary converter.

[0081] The output of each diesel generator is connected to the input of the traction converter. The output of the traction converter and the output of each battery are connected to the input of the auxiliary converter. The output of the auxiliary converter is connected to the traction motor and the power supply load.

[0082] The traction converter is used to convert the AC power output from the diesel generator into DC power, and the auxiliary converter is used to convert the DC power output from the traction converter and the battery into AC power.

[0083] The process of determining energy conversion efficiency includes:

[0084] Determine the energy conversion efficiency of the traction converter, auxiliary converter, diesel generator, and battery.

[0085] Please refer to Figure 2 A diesel generator consists of a diesel engine and a generator. The output of the diesel engine is connected to the input of the generator. The diesel engine drives the generator to output AC power. The AC power is first converted to DC power by a traction converter for transmission, and then filtered before being converted back to AC power for output to the traction motor and auxiliary power supply equipment. If there are two diesel generators, then they are diesel engine 1, diesel engine 2, generator 1, and generator 2.

[0086] There are usually two batteries, namely battery 1 and battery 2. The DC power output from the batteries is converted into AC power by the traction converter and then output to the traction motor and auxiliary power supply equipment.

[0087] Both traction converters and auxiliary converters generate power losses, so energy conversion efficiency needs to be taken into account.

[0088] In some embodiments, determining the energy conversion efficiency of the auxiliary converter includes:

[0089] The power required for the auxiliary converter to convert AC to DC is determined based on its output power and efficiency. The expression for the power required for the auxiliary converter to convert AC to DC is as follows:

[0090] P_AuxOutputpower_Tcu'=P_AuxOutputpower_Tcu / η_AUX_inv;

[0091] Where P_AuxOutputpower_Tcu' is the power required for the auxiliary converter to convert AC to DC, P_AuxOutputpower_Tcu is the output power of the auxiliary converter, and η_AUX_inv is the efficiency of the auxiliary converter.

[0092] The output power of the auxiliary converter must meet the total demand of the DC link loads such as train lighting, braking, and air conditioning. However, the voltage drop of the converter's switching devices during conduction, the energy loss during switching, and the losses due to the equivalent series resistance of capacitors and the hysteresis loss of inductors all contribute to energy loss. If efficiency is ignored and the converter output is directly determined based on the power demand of the DC link, the actual power delivered to the DC link will be lower than the target value due to losses, resulting in insufficient power supply to auxiliary equipment and problems such as insufficient air conditioning cooling and slow response of the braking system. For example, if a train's DC link load requires 50kW of power, and the converter efficiency is 90%, then the converter output needs to be approximately 55.6kW to ensure that the DC link ultimately obtains 50kW of usable power.

[0093] Taking two auxiliary converters as an example, the power conversion of the auxiliary converters: when converting the output power of the auxiliary converters to the power required by the DC link, the efficiency of the auxiliary converters must be considered. The efficiency formulas for the two auxiliary converters are as follows:

[0094] P_AuxOutputpower_Tcu1'=P_AuxOutputpower_Tcu1 / η_AUX_inv;

[0095] P_AuxOutputpower_Tcu2'=P_AuxOutputpower_Tcu2 / η_AUX_inv;

[0096] P_AuxOutputpower_Tcu1' is the power required for the first auxiliary converter to convert AC to DC, P_AuxOutputpower_Tcu1 is the output power of the first auxiliary converter, P_AuxOutputpower_Tcu2' is the power required for the second auxiliary converter to convert AC to DC, and P_AuxOutputpower_Tcu2 is the output power of the second auxiliary converter.

[0097] In some embodiments, determining the energy conversion efficiency of a diesel generator includes:

[0098] The power converted from the diesel generator's output power to the DC link power is determined based on the diesel generator's output power, power generation efficiency, and converter efficiency. The expression for converting the diesel generator's output power to the DC link power is as follows:

[0099] P_Diesel_actual'=P_Diesel_actual×η_gen×η_gen-inv;

[0100] Where P_Diesel_actual' is the power converted from the output power of the diesel generator to the DC link, P_Diesel_actual is the output power of the diesel generator, η_gen is the power generation efficiency of the diesel generator, and η_gen-inv is the operating efficiency of the converter of the diesel generator.

[0101] Diesel generators suffer from various losses, including mechanical losses, iron losses, and excitation losses. Voltage drops in the switching devices of the converter and capacitor / resistance losses also contribute to energy loss. If efficiency is ignored and the diesel engine power is set solely based on the DC link load demand, the actual power input to the DC link will be far lower than the target value after accounting for these losses.

[0102] Taking two diesel generators as an example, the power conversion of the diesel generators: When converting the actual power of the diesel engine to DC link power, considering the efficiency of the diesel generators and converters, the efficiency formulas for the two diesel generators are as follows:

[0103] P_Diesel_actual'=P_Diesel_actual1×η_gen×η_gen-inv;

[0104] P_Diesel_actua2'=P_Diesel_actual2×η_gen×η_gen-inv;

[0105] Wherein, P_Diesel_actual1' is the power converted from the output power of the first diesel generator to the DC link, P_Diesel_actual1 is the output power of the first diesel generator, P_Diesel_actual2' is the power converted from the output power of the second diesel generator to the DC link, and P_Diesel_actual2 is the output power of the second diesel generator.

[0106] In some embodiments, determining the energy conversion efficiency of a battery includes:

[0107] The power converted from battery discharge power to DC link is determined based on the battery discharge power and the chopper efficiency. The expression for the power converted from battery discharge power to DC link is as follows:

[0108] P_actual_dischargePower'=P_actual_dischargePower×η_batt-inv;

[0109] Where P_actual_dischargePower' is the power converted from battery discharge power to DC link, P_actual_dischargePower is the battery discharge power, and η_batt-inv is the chopper efficiency of the battery.

[0110] Battery voltage gradually decreases during discharge, while DC-DC loads (such as communication equipment and locomotive auxiliary equipment) have stable power and voltage requirements. The battery chopper needs to perform boost / buck conversion to match the DC-DC voltage, but losses will cause the actual output power to be lower than the battery's discharge power. If efficiency is ignored and the battery discharge power is set according to load requirements, the power received by the DC-DC link will be insufficient after chopper losses, leading to load anomalies.

[0111] Taking two batteries as an example, the battery discharge power conversion is as follows: When converting the battery discharge power to DC link power, considering the battery chopper efficiency, the efficiency formulas for the two batteries are as follows:

[0112] P_actual_dischargePower1'=P_actual_dischargePower1×η_batt-inv;

[0113] P_actual_dischargePower2'=P_actual_dischargePower2×η_batt-inv;

[0114] Wherein, P_actual_dischargePower1' is the power converted from the first battery discharge power to the DC link, P_actual_dischargePower1 is the discharge power of the first battery, P_actual_dischargePower2' is the power converted from the second battery discharge power to the DC link, and P_actual_dischargePower2 is the discharge power of the second battery.

[0115] In some embodiments, after determining the current operating mode of the power source, the method further includes:

[0116] When the current operating mode is diesel generator mode or hybrid mode, the first diesel generator is started when the target power is greater than or equal to the first power.

[0117] When the current operating mode is diesel generator mode or hybrid mode, the first diesel generator that has been started will be shut down when the target power is less than or equal to the second power.

[0118] When the current operating mode is diesel generator mode or hybrid mode, start the second diesel generator when the target power is greater than or equal to the third power.

[0119] When the current operating mode is diesel generator mode or hybrid mode, and the target power is less than or equal to the fourth power, shut down the second diesel generator that has been started;

[0120] Among them, the fourth power, the third power, the first power, and the second power decrease in sequence.

[0121] Based on the time average value of DC link power demand and the start / stop threshold set by the battery SoC, the specific values ​​are as follows: P1=60, P2=50, P3=300, P4=200. These values ​​are determined according to the output power of the diesel engine and are the values ​​set in the actual project. They can be set according to actual needs.

[0122] Starting a single diesel engine: Hybrid or diesel mode activated, and power requirement ≥ P1.

[0123] Stop a single diesel engine: Hybrid or diesel mode activated, and power requirement ≤ P2.

[0124] Start a second diesel engine: Hybrid or diesel mode activated, with power requirement ≥ P3.

[0125] Stop the second diesel engine: Hybrid or diesel mode activated, and power requirement ≤ P4.

[0126] When starting a diesel engine, prioritize the engine with the shortest total running time to balance engine wear. This means starting with the engine that consumes more fuel but has a shorter running time, ensuring that the running time and remaining fuel levels of the two engines are similar, which facilitates subsequent maintenance.

[0127] In some embodiments, when the operating mode is battery mode, determining the battery output power based on the target power and energy conversion efficiency includes:

[0128] When the remaining charge of the battery is greater than the first charge and the maximum discharge power is greater than 0, the output power of the battery is determined according to the target power and energy conversion efficiency. The expression for the output power of the battery is P_actual_dischargePower=P_DC_setpoint / η_batt-inv;

[0129] Where P_actual_dischargePower is the battery's discharge power, P_DC_setpoint is the target power of the DC link, and η_batt-inv is the battery's chopper efficiency.

[0130] The traction battery provides power, and the actual discharge power of the battery is calculated based on the target power of the DC link and the efficiency of the battery chopper.

[0131] Activation via TDD (Technical and Diagnostic Display, Train Control Interface) requires that the dual battery SoC (State of Charge) be greater than 20% and the maximum discharge power be greater than 0. After activation, graded warnings and controls are performed based on the battery SoC status.

[0132] In some embodiments, when the operating mode is diesel generator mode, the output power of each diesel generator is determined based on the target power and energy conversion efficiency, including:

[0133] The number of diesel generators is determined when the fuel level in the fuel tank of the diesel generator is higher than the minimum fuel level.

[0134] When a diesel generator operates as a single unit, its output power is determined based on the target power and energy conversion efficiency. The expression for the output power of a single diesel generator is as follows:

[0135] P_Diesel_setpoint=(P_DC1_setpoint+P_DC2_setpoint) / (η_gen×η_gen-inv);

[0136] Where P_Diesel_setpoint is the output power of a single diesel generator, P_DC1_setpoint is the target power of the first DC link, P_DC2_setpoint is the target power of the second DC link, η_gen is the power generation efficiency of the diesel generator, and η_gen-inv is the operating efficiency of the diesel generator converter.

[0137] When two diesel generators are running, the output power of each generator is determined based on the target power and energy conversion efficiency. The expression for the output power of each diesel generator is as follows:

[0138] P_DieselX_setpoint=P_DCX_setpoint / (η_gen×η_gen-inv);

[0139] Where P_DieselX_setpoint is the output power of the Xth single diesel generator, and P_DCX_setpoint is the target power of the Xth DC link, X=1,2.

[0140] The diesel engine is ready when activated via TDD and the fuel level in the tank is >0%.

[0141] When a single diesel engine is running, the target power is calculated based on the total power demand and efficiency conversion of the DC link. When two diesel engines are running, the power demand of the DC link is calculated separately for each engine.

[0142] It should also be noted that when operating with a single diesel engine or without a diesel engine:

[0143] P_DC1_max=(P_Diesel1_max'+P_Diesel2_max') / 2+P_Batt1_max';

[0144] P_DC2_max=(P_Diesel1_max'+P_Diesel2_max') / 2+P_Batt2_max'.

[0145] When both diesel engines are running:

[0146] P_DC1_max=P_Diesel1_max'+P_Batt1_max';

[0147] P_DC2_max=P_Diesel2_max'+P_Batt2_max'.

[0148] P_DC1_max is the maximum available power of the first DC link, P_DC2_max is the maximum available power of the second DC link, P_Diesel1_max' is the maximum output power of the first diesel engine, P_Diesel2_max' is the maximum output power of the first diesel engine, P_Batt1_max' is the maximum output power of the first battery, and P_Batt2_max' is the maximum output power of the second battery.

[0149] In some embodiments, when the operating mode is hybrid mode, the output power of the battery and each diesel generator is determined based on the target power, the battery capacity, the operating efficiency of the diesel generator, and the energy conversion efficiency, including:

[0150] The DC link is powered by a battery.

[0151] Start the diesel generator when the battery charge is less than the initial charge level;

[0152] When the diesel generator is running as a single unit, if the target power is greater than the maximum output power of the diesel generator and the battery charge is greater than the first charge, the diesel generator is controlled to work at the maximum output power. The battery output power is the difference between the target power and the maximum output power.

[0153] When the diesel generator is running as a single unit, if the target power is less than the maximum output power of the diesel generator, greater than the optimal output power of the diesel generator, and the battery charge is less than the second charge, the diesel generator is controlled to operate at the optimal output power. The battery output power is the difference between the target power and the optimal output power, and the second charge is greater than the first charge.

[0154] When two diesel generators are running, the output power of each generator is determined based on the target power and energy conversion efficiency. The expression for the output power of each diesel generator is as follows:

[0155] P_DieselX_setpoint=P_DCX_setpoint / (η_gen×η_gen-inv);

[0156] Where P_DieselX_setpoint is the output power of the Xth single diesel generator, and P_DCX_setpoint is the target power of the Xth DC link, X=1,2.

[0157] No diesel engine operation: If at least one battery SoC < 20%, start the diesel engine.

[0158] Single diesel engine operation: Power demand exceeds the diesel engine's maximum power, battery SoC ≥ 20%: The diesel engine outputs maximum power, and the battery supplements the remaining power. Power demand is between the diesel engine's optimal power (360kW) and maximum power, battery SoC ≥ 80%: The battery shares some power, allowing the diesel engine to operate in its optimal efficiency range.

[0159] Dual diesel engine operation: Calculate the target power based on the corresponding DC link power requirements and efficiency conversion.

[0160] In some embodiments, it also includes:

[0161] Set the target charging capacity for the battery;

[0162] Control the diesel generator to supply power to the storage battery;

[0163] When the battery reaches the target charging level, the diesel generator is controlled to stop supplying power to the battery.

[0164] (1) Explicit charging mode:

[0165] Used to actively charge the battery, start the diesel engine after activation (if not running), set the target charging power; stop charging or exit the mode according to the battery SoC status.

[0166] (2) Deep discharge protection:

[0167] To prevent the battery from over-discharging, it is activated to start the diesel engine and charge the battery; when the battery SoC returns to a safe value (>15%), the protection is deactivated.

[0168] Figure 3 This is a schematic diagram of a vehicle energy management device provided by the present invention. The vehicle energy management device includes:

[0169] Memory 31 is used to store computer programs;

[0170] The processor 32 is used to implement the steps of the above-described vehicle energy management method when executing a computer program.

[0171] The description of the energy management device for the vehicle provided in this application is given in the above embodiments and will not be repeated here.

[0172] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0173] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0174] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily 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 invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An energy management method of a vehicle, characterized by, The application relates to a power source for a vehicle, and relates to a method for determining the output power of the power source. The method comprises the following steps: determining a target power corresponding to a target traction force of the vehicle; determining an operation mode of the current power source, wherein the operation mode comprises at least two of a battery mode, a diesel generator mode and a hybrid mode; when the operation mode is the battery mode, determining the output power of the battery according to the target power and an energy conversion efficiency; when the operation mode is the diesel generator mode, determining the output power of each diesel generator according to the target power and the energy conversion efficiency; 2. The energy management method of a vehicle according to claim 1, characterized by, when the operation mode is the hybrid mode, determining the output power of the battery and each diesel generator according to the target power, the power of the battery, the operation efficiency of the diesel generator and the energy conversion efficiency. The power source comprises at least one diesel generator and a battery, and the vehicle further comprises a traction converter and an auxiliary converter; the output end of each diesel generator is connected with the input end of the traction converter, the output end of the traction converter and the output end of each battery are connected with the input end of the auxiliary converter, and the output end of the auxiliary converter is connected with a traction motor and a power supply load; the traction converter is used for converting the alternating current output by the diesel generator into direct current, and the auxiliary converter is used for converting the direct current output by the traction converter and the battery into alternating current; the energy conversion efficiency is determined by the following steps:

3. The energy management method for a vehicle according to claim 2, characterized by, determining the energy conversion efficiency of the traction converter, the auxiliary converter, the diesel generator and the battery. The energy conversion efficiency of the auxiliary converter is determined by the following steps: determining the power required by the auxiliary converter for converting alternating current into direct current according to the output power of the auxiliary converter and the efficiency of the auxiliary converter, wherein the expression of the power required by the auxiliary converter for converting alternating current into direct current is as follows: P_AuxOutputpower_Tcu'=P_AuxOutputpower_Tcu / η_AUX_inv; 4. The energy management method for a vehicle according to claim 2, characterized by, wherein the P_AuxOutputpower_Tcu' is the power required by the auxiliary converter for converting alternating current into direct current, P_AuxOutputpower_Tcu is the output power of the auxiliary converter, and η_AUX_inv is the efficiency of the auxiliary converter. The energy conversion efficiency of the diesel generator is determined by the following steps: determining the power of the output power of the diesel generator converted into a direct current link according to the output power of the diesel generator, the power generation efficiency of the diesel generator and the working efficiency of the converter of the diesel generator, wherein the expression of the power of the output power of the diesel generator converted into the direct current link is as follows: P_Diesel_actual'=P_Diesel_actual×η_gen×η_gen-inv; P_actual_dischargePower' = P_actual_dischargePower x η_batt-inv; wherein P_actual_dischargePower' is the power converted from the discharging power of the battery to the DC link, P_actual_dischargePower is the discharging power of the battery, and η_batt-inv is the chopper efficiency of the battery.

5. The energy management method for a vehicle according to claim 2, characterized by, determining the energy conversion efficiency of the battery, comprising: determining the power converted from the discharging power of the battery to the DC link according to the discharging power of the battery and the chopper efficiency of the battery, the expression of the power converted from the discharging power of the battery to the DC link being: P_actual_dischargePower' = P_actual_dischargePower x η_batt-inv; wherein P_actual_dischargePower' is the power converted from the discharging power of the battery to the DC link, P_actual_dischargePower is the discharging power of the battery, and η_batt-inv is the chopper efficiency of the battery. determining the energy conversion efficiency of the battery, comprising:

6. The energy management method of a vehicle according to claim 1, characterized by, when the target power is greater than or equal to the first power in the diesel generator mode or the hybrid mode, starting the first diesel generator; when the target power is less than or equal to the second power in the diesel generator mode or the hybrid mode, closing the started first diesel generator; when the target power is greater than or equal to the third power in the diesel generator mode or the hybrid mode, starting the second diesel generator; when the target power is less than or equal to the fourth power in the diesel generator mode or the hybrid mode, closing the started second diesel generator; wherein the fourth power, the third power, the first power and the second power decrease in turn. when the running mode is the battery mode, determining the output power of the battery according to the target power and the energy conversion efficiency, comprising:

7. The energy management method for a vehicle according to any one of claims 1 to 6, characterized by, when the remaining power of the battery is greater than the first power and the maximum discharging power is greater than 0, determining the output power of the battery according to the target power and the energy conversion efficiency, the expression of the output power of the battery being P_actual_dischargePower = P_DC_setpoint / η_batt-inv; wherein P_actual_dischargePower is the discharging power of the battery, P_DC_setpoint is the target power of the DC link, and η_batt-inv is the chopper efficiency of the battery. when the running mode is the diesel generator mode, determining the output power of each diesel generator according to the target power and the energy conversion efficiency, comprising:

8. The energy management method for a vehicle according to any one of claims 1 to 6, characterized by, determining the number of diesel generators when the oil level of the oil tank of the diesel generator is greater than the minimum oil level; ​ In the diesel generator for single operation, the output power of the diesel generator is determined according to the target power and the energy conversion efficiency, and the expression of the output power of the single diesel generator is: P_Diesel_setpoint=(P_DC1_setpoint+P_DC2_setpoint) / (η_gen×η_gen-inv); Wherein, P_Diesel_setpoint is the output power of the single diesel generator, P_DC1_setpoint is the target power of the first DC link, P_DC2_setpoint is the target power of the second DC link, η_gen is the power generation efficiency of the diesel generator, and η_gen-inv is the working efficiency of the converter of the diesel generator. In the diesel generator for double operation, the output power of the diesel generator is determined according to the target power and the energy conversion efficiency, and the expression of the output power of each diesel generator is: P_DieselX_setpoint=P_DCX_setpoint / (η_gen×η_gen-inv); Wherein, P_DieselX_setpoint is the output power of the Xth single diesel generator, P_DCX_setpoint is the target power of the Xth DC link, and X=1, 2.

9. The energy management method for a vehicle according to any one of claims 1 to 6, characterized by, In the hybrid mode, the output power of the battery and each diesel generator is determined according to the target power, the power of the battery, the operation efficiency of the diesel generator and the energy conversion efficiency, including: The DC link is powered by the battery; When the power of the battery is less than the first power, the diesel generator is started; When the diesel generator is single operation, when the target power is greater than the maximum output power of the diesel generator and the power of the battery is greater than the first power, the diesel generator is controlled to work at the maximum output power, and the battery output power is the difference between the target power and the maximum output power; When the diesel generator is single operation, when the target power is less than the maximum output power of the diesel generator, greater than the optimal output power of the diesel generator, and the power of the battery is less than the second power, the diesel generator is controlled to work at the optimal output power, and the battery output power is the difference between the target power and the optimal output power, and the second power is greater than the first power. In the diesel generator for double operation, the output power of the diesel generator is determined according to the target power and the energy conversion efficiency, and the expression of the output power of each diesel generator is: P_DieselX_setpoint=P_DCX_setpoint / (η_gen×η_gen-inv); Wherein, P_DieselX_setpoint is the output power of the Xth single diesel generator, P_DCX_setpoint is the target power of the Xth DC link, and X=1, 2. The target charging power of the battery is set. controlling the diesel generator to supply power to the battery; controlling the diesel generator to stop supplying power to the battery when the battery reaches the target charge level.

10. An energy management apparatus for a vehicle, characterized by comprising: a memory for storing a computer program; a processor for implementing the steps of the energy management method of the vehicle according to any one of claims 1 to 9 when executing the computer program.

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