Hybrid power system of hydrogen internal combustion engine of long-endurance commercial vehicle and vehicle-mounted hydrogen storage mode evaluation

Abstract

The invention discloses a long-endurance commercial vehicle hydrogen internal combustion engine hybrid power system and vehicle-mounted hydrogen storage mode evaluation, and relates to the technical field of hydrogen internal combustion engines. The long-endurance commercial vehicle hydrogen internal combustion engine hybrid power system comprises a hydrogen internal combustion engine, a waste heat recovery module, a vehicle-mounted hydrogen storage module and a power generation range extending module; the exhaust end of the hydrogen internal combustion engine is connected with the input end of the waste heat recovery module, the output end of the waste heat recovery module is connected with the input end of the vehicle-mounted hydrogen storage module, the output end of the vehicle-mounted hydrogen storage module is connected with the air inlet end of the hydrogen internal combustion engine, and the output end of the power generation range extending module is connected with the input end of the vehicle-mounted hydrogen storage module; according to the long-endurance commercial vehicle hydrogen internal combustion engine hybrid power system and the vehicle-mounted hydrogen storage mode evaluation method, the energy conservation equation and the analysis equation are combined, waste heat of the hydrogen internal combustion engine can be reasonably utilized, and a proper hydrogen storage mode can be selected.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen internal combustion engines, and in particular to a hybrid power system of a hydrogen internal combustion engine for a long-range commercial vehicle and an evaluation of an on-board hydrogen storage method. Background Art

[0002] Direct injection hydrogen internal combustion engines require high injection pressure and the uniformity of the mixture increases slightly with the increase of injection pressure. The increased turbulent kinetic energy due to the increase in injection pressure promotes the improvement of the mixing process, thereby improving BTE (brakethermal efficiency). However, high injection pressure will lead to a decrease in the ratio of available hydrogen in the hydrogen storage tank. For example, for a power system equipped with a 35MPa hydrogen storage tank and using a 12MPa injection pressure, if there is no on-board hydrogen compressor, the hydrogen in the hydrogen storage tank with a pressure lower than the injection pressure cannot be fully utilized, which greatly reduces the cruising range of hydrogen-powered vehicles; due to the shortened cruising range of high-pressure compressed gaseous hydrogen, low weight and volume energy density, and safety risks, a lot of research is needed before hydrogen is applied to vehicles. The research on high-density hydrogen storage methods has attracted considerable attention. Various hydrogen storage methods require a certain reaction temperature to proceed, and a certain amount of energy is also required when releasing hydrogen, so the hydrogen storage method is a major difficulty.

[0003] Therefore, this application proposes an evaluation of a long-range commercial vehicle hydrogen internal combustion engine hybrid system and on-board hydrogen storage method to solve the above-mentioned technical problems. Summary of the invention

[0004] The purpose of the present invention is to provide a long-range commercial vehicle hydrogen internal combustion engine hybrid power system and an on-board hydrogen storage method evaluation, which can reasonably utilize the waste heat of the hydrogen internal combustion engine and select a suitable hydrogen storage method by combining the energy conservation equation and the exergy analysis equation.

[0005] To achieve the above-mentioned objectives, the present invention provides a long-range commercial vehicle hydrogen internal combustion engine hybrid power system, comprising a hydrogen internal combustion engine, a waste heat recovery module, an on-board hydrogen storage module and a power generation and range extension module, wherein the power output side of the hydrogen internal combustion engine is connected to the input end of the power generation and range extension module, the exhaust end of the hydrogen internal combustion engine is connected to the input end of the waste heat recovery module, the output end of the waste heat recovery module is connected to the input end of the on-board hydrogen storage module, the output end of the on-board hydrogen storage module is connected to the intake end of the hydrogen internal combustion engine, and the output end of the power generation and range extension module is connected to the input end of the on-board hydrogen storage module.

[0006] Preferably, the waste heat recovery module includes a turbine, a low-temperature heat exchanger and a Rankine cycle waste heat recovery device, the input end of the turbine is connected to the exhaust end of the hydrogen internal combustion engine, the output end of the turbine is respectively connected to the input ends of the high-temperature heat exchanger and the compressor, the output end of the compressor is connected to the input end of the intercooler heat exchanger, the output end of the intercooler heat exchanger is connected to the intake end of the hydrogen internal combustion engine, the hydrogen internal combustion engine is provided with a coolant, the coolant enters the low-temperature heat exchanger from the inside of the hydrogen internal combustion engine, the input end of the Rankine cycle waste heat recovery device collects the waste heat generated by the low-temperature heat exchanger, the high-temperature heat exchanger and the intercooler heat exchanger, and the output end of the Rankine cycle waste heat recovery device is connected to the input end of the on-board hydrogen storage module.

[0007] Preferably, the power generation and range extender module includes a generator, a first power converter and a second power converter, the input end of the generator is connected to the hydrogen internal combustion engine, the output end of the generator is connected to the drive motor, the input end of the first power converter is connected to the generator, the output end of the first power converter is connected to the input end of the battery, the output end of the battery is respectively connected to the drive motor and the second power converter, and the output end of the second power converter is connected to the on-board hydrogen storage module.

[0008] The present invention also provides an evaluation of an onboard hydrogen storage method for a long-range commercial vehicle hydrogen internal combustion engine hybrid system, comprising the following steps: Step 1: Select an on-board hydrogen storage method to be evaluated and determine the reaction temperature range of the on-board hydrogen storage method; Step 2: According to the driving conditions of different commercial vehicle hybrid systems, the power, effective thermal efficiency and hydrogen calorific value required under the driving conditions are determined to select a hybrid mode; Step 3: Calculate the hydrogen flow rate under the driving condition according to the power, effective thermal efficiency and hydrogen calorific value obtained in step 2; Step 4: Calculate the waste heat available energy according to the energy conservation equation and the exergy equation; Step 5, measuring the high-temperature exhaust gas temperature by a temperature sensor provided at the exhaust outlet of the hydrogen internal combustion engine, judging whether the hydrogen storage method is reasonable according to the high-temperature exhaust gas temperature during the operation of the hydrogen internal combustion engine, and judging that the hydrogen storage method is reasonable when the reaction temperature is ≤ the high-temperature exhaust gas temperature; and reselecting the hydrogen storage method when the reaction temperature is > the high-temperature exhaust gas temperature; Step 6, calculating the hydrogen release energy and compressor power consumption according to the hydrogen storage method selected in step 5; Step 7: Perform energy evaluation based on the hydrogen release energy and compressor power consumption obtained in step 6. When the hydrogen release energy + compressor power consumption ≤ the available energy of the hydrogen internal combustion engine waste heat, the energy required by the on-board hydrogen storage module is completely provided by the waste heat recovery module; when the hydrogen release energy + compressor power consumption > the available energy of the hydrogen internal combustion engine waste heat, the energy difference required by the on-board hydrogen storage module is supplemented by the battery; Step 8: Through the energy evaluation of step 7, determine whether the on-board hydrogen storage method can utilize the waste heat energy of the hydrogen internal combustion engine to work. If it can utilize the waste heat energy of the hydrogen internal combustion engine to work, it is determined that the waste heat utilization rate is improved; otherwise, return to step 2.

[0009] Preferably, the hybrid mode of step 2 includes direct drive of a hydrogen internal combustion engine and battery range extension.

[0010] Preferably, the step 3 calculates the hydrogen flow rate under the driving condition, and the calculation formula is as follows: (1) Where: is power, unit W; is the hydrogen flow rate, in kg / h; M is the calorific value of hydrogen, in MJ / kg; For effective thermal efficiency.

[0011] Preferably, the energy conservation equation of step 4 is as follows: (2) in: The energy brought by hydrogen fuel, The energy brought by the intake air, The work done by a hydrogen internal combustion engine, The energy taken away by the intercooler heat exchanger, The energy taken away by the high-temperature exhaust gas, The energy taken away by the coolant, Loss of energy for others.

[0012] Preferably, the expression for calculating the waste heat available energy by the exergy equation in step 4 is as follows: (3) (4) (5) (6) (7) (8) (9) (10)

[0013] in, is the available energy in the intake air of a hydrogen internal combustion engine. is the available energy in the fuel, is the available energy contained in the exhaust gas, is the available energy contained in the coolant, The work done by a hydrogen internal combustion engine, is the mass flow rate of intake air, is the specific heat capacity of air, is the ambient temperature, is the mass flow rate of hydrogen, is the mass flow rate of exhaust gas, is the specific enthalpy at exhaust temperature and pressure, is the specific enthalpy of ambient temperature and ambient pressure, is the entropy at exhaust temperature and pressure, is the entropy of ambient temperature and ambient pressure, is the utilization rate of available energy in exhaust gas, is the flow rate of coolant, is the temperature of the coolant, is the efficiency of the available energy in the coolant, The available efficiency of hydrogen fuel.

[0014] Preferably, the calculation formula of hydrogen release energy and compressor power consumption in step 6 is as follows: (11) (12)

[0015] in, is the specific enthalpy of different storage materials at the hydrogen release temperature, is the mass flow rate through the compressor, is the dehydrogenation enthalpy, is the hydrogen mass flow rate, The power required to compress a substance to a certain pressure. is the flow rate out of the compressor, is the flow rate entering the compressor, The efficiency of the compressor.

[0016] Therefore, the present invention adopts the long-range commercial vehicle hydrogen internal combustion engine hybrid system and on-board hydrogen storage method evaluation of the above-mentioned structure, which has the following beneficial effects: by recovering the waste heat generated by the hydrogen internal combustion engine during operation to generate new energy, the waste heat is used to reduce dependence on energy, reduce the emission of greenhouse gases and other pollutants, help protect the environment, greatly improve the overall energy utilization efficiency, reduce energy consumption costs, and improve economic benefits; choosing a suitable hydrogen storage method can ensure a stable supply of hydrogen, help vehicles achieve a longer cruising range, reduce the risk of hydrogen leakage and explosion, and have double guarantees in terms of performance and safety.

[0017] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the long-range commercial vehicle hydrogen internal combustion engine hybrid power system of the present invention; Figure 2 This is a composition diagram of the long-range commercial vehicle hydrogen internal combustion engine hybrid power system of the present invention; Figure 3 A flow chart for evaluating the hydrogen storage method of the long-range commercial vehicle hydrogen internal combustion engine hybrid system of the present invention; Figure 4 A comparison diagram of the waste heat temperature of a hydrogen internal combustion engine and the hydrogen storage reaction temperature of a hydrogen storage method evaluation embodiment of a long-range commercial vehicle hydrogen internal combustion engine hybrid system of the present invention; Figure 5 A comparison chart of the effective energy of waste heat of a hydrogen internal combustion engine and the energy consumption of hydrogen storage in an embodiment of the present invention for evaluating the hydrogen storage method of a hydrogen internal combustion engine hybrid system for a long-range commercial vehicle; Reference numerals 1. Hydrogen internal combustion engine; 2. Waste heat recovery module; 3. On-board hydrogen storage module; 4. Power generation and range extension module; 21. Turbine; 22. High-temperature heat exchanger; 23. Compressor; 24. Intercooler heat exchanger; 25. Coolant; 26. Low-temperature heat exchanger; 27. Rankine cycle waste heat recovery device; 41. Generator; 42. Drive motor; 43. Battery; 44. First power converter; 45. Second power converter. DETAILED DESCRIPTION

[0019] The following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] like Figure 1 and Figure 2As shown, a long-range commercial vehicle hydrogen internal combustion engine hybrid power system includes a hydrogen internal combustion engine 1, a waste heat recovery module 2, an on-board hydrogen storage module 3 and a power generation and range extension module 4. The power output side of the hydrogen internal combustion engine 1 is connected to the input end of the power generation and range extension module 4, the exhaust end of the hydrogen internal combustion engine 1 is connected to the input end of the waste heat recovery module 2, the output end of the waste heat recovery module 2 is connected to the input end of the on-board hydrogen storage module 3, the output end of the on-board hydrogen storage module 3 is connected to the intake end of the hydrogen internal combustion engine 1, and the output end of the power generation and range extension module 4 is connected to the input end of the on-board hydrogen storage module 3.

[0021] The waste heat recovery module 2 includes a turbine 21, a low-temperature heat exchanger 26 and a Rankine cycle waste heat recovery device 27. The input end of the turbine 21 is connected to the exhaust end of the hydrogen internal combustion engine 1, and the output end of the turbine 21 is respectively connected to the input end of the high-temperature heat exchanger 22 and the compressor 23. The output end of the compressor 23 is connected to the input end of the intercooler heat exchanger 24. The output end of the intercooler heat exchanger 24 is connected to the intake end of the hydrogen internal combustion engine 1. The hydrogen internal combustion engine 1 is provided with a coolant 25 for cooling. Liquid 25 enters the low-temperature heat exchanger 26 from the inside of the hydrogen internal combustion engine 1. The input end of the Rankine cycle waste heat recovery device 27 collects the waste heat generated by the low-temperature heat exchanger 26, the high-temperature heat exchanger 22 and the intercooler heat exchanger 24. The output end of the Rankine cycle waste heat recovery device is connected to the input end of the on-board hydrogen storage module 3. Specifically, the hydrogen internal combustion engine 1 will dissipate heat through the exhaust manifold, intercooler, heat exchanger and other components during operation. These are also the three main waste heat sources of the hydrogen internal combustion engine. According to the attached Figure 2 The three parts are as follows: 1. The high-temperature exhaust gas generated by the hydrogen internal combustion engine 1 passes through the turbine 21 and then passes through the high-temperature heat exchanger 22 for heat exchange; 2. The fresh air passing through the compressor 23 has a higher temperature and pressure and needs to pass through the intercooler heat exchanger 24 for heat exchange. This part of the heat also has usable energy; 3. The hydrogen internal combustion engine 1 has a high body temperature during operation. In order to ensure the reliability of the body, it is necessary to increase the coolant to cool the body. The used coolant can be heat exchanged through the low-temperature heat exchanger 26. The heat of these three parts is recovered and converted through the Rankine cycle waste heat recovery device 27.

[0022] The power generation and range extension module 4 includes a generator 41, a first power converter 44 and a second power converter 45. The input end of the generator 41 is connected to the hydrogen internal combustion engine 1, and the output end of the generator 41 is connected to the drive motor 42. The input end of the first power converter 44 is connected to the generator 41, and the output end of the first power converter 44 is connected to the input end of the battery 43. The output end of the battery 43 is respectively connected to the drive motor 42 and the second power converter 45, and the output end of the second power converter 45 is connected to the on-board hydrogen storage module 3.

[0023] like Figure 3 As shown in the figure, the evaluation of the onboard hydrogen storage method of the long-range commercial vehicle hydrogen internal combustion engine hybrid system includes the following steps: Step 1: Select an on-board hydrogen storage method to be evaluated and determine the reaction temperature range of the on-board hydrogen storage method; Step 2: According to the driving conditions of different commercial vehicle hybrid systems, the required power, effective thermal efficiency and hydrogen calorific value are determined to select a hybrid mode, wherein the hybrid mode includes hydrogen internal combustion engine direct drive and battery range extension; Step 3: Calculate the hydrogen flow rate under the driving condition according to the power, effective thermal efficiency and hydrogen calorific value obtained in step 2; Calculate the hydrogen flow rate under the driving condition using the following formula: (1)

[0024] Where: is power, unit W; is the hydrogen flow rate, in kg / h; M is the calorific value of hydrogen, in MJ / kg; is the effective thermal efficiency; Step 4: Calculate the waste heat available energy according to the energy conservation equation and the exergy equation; The energy conservation equation is as follows: (2)

[0025] in: The energy brought by hydrogen fuel, The energy brought by the intake air, The work done by a hydrogen internal combustion engine, The energy taken away by the intercooler heat exchanger, The energy taken away by the high-temperature exhaust gas, The energy taken away by the coolant, Loss of energy for others; The expression for calculating the waste heat available energy using the exergy equation is as follows: (3) (4) (5) (6) (7) (8) (9) (10)

[0026] in, is the available energy in the intake air of a hydrogen internal combustion engine. is the available energy in the fuel, is the available energy contained in the exhaust gas, is the available energy contained in the coolant, The work done by a hydrogen internal combustion engine, is the mass flow rate of intake air, is the specific heat capacity of air, is the ambient temperature, is the mass flow rate of hydrogen, is the mass flow rate of exhaust gas, is the specific enthalpy at exhaust temperature and pressure, is the specific enthalpy of ambient temperature and ambient pressure, is the entropy at exhaust temperature and pressure, is the entropy of ambient temperature and ambient pressure, is the utilization rate of available energy in exhaust gas, is the flow rate of coolant, is the temperature of the coolant, is the efficiency of the available energy in the coolant, The available efficiency of hydrogen fuel; Step 5, measuring the high-temperature exhaust gas temperature by a temperature sensor provided at the exhaust outlet of the hydrogen internal combustion engine, judging whether the hydrogen storage method is reasonable according to the high-temperature exhaust gas temperature during the operation of the hydrogen internal combustion engine, and judging that the hydrogen storage method is reasonable when the reaction temperature is ≤ the high-temperature exhaust gas temperature; and reselecting the hydrogen storage method when the reaction temperature is > the high-temperature exhaust gas temperature; Step 6: Calculate the hydrogen release energy and compressor power consumption according to the hydrogen storage method selected in step 5; various hydrogen storage methods require a certain amount of hydrogen release energy when releasing hydrogen. This energy has two sources in the present invention: waste heat energy of the hydrogen internal combustion engine and battery replenishment. In addition, after the hydrogen stored in the vehicle is released, it needs to be pressurized by a hydrogen compressor to reach the target hydrogen pressure. The calculation formula for hydrogen release energy and compressor power consumption is as follows: (11) (12)

[0027] in, is the specific enthalpy of different storage materials at the hydrogen release temperature, is the mass flow rate through the compressor, is the dehydrogenation enthalpy, is the hydrogen mass flow rate, The power required to compress a substance to a certain pressure. is the flow rate out of the compressor, is the flow rate entering the compressor, is the compressor working efficiency; Step 7: Perform energy evaluation based on the hydrogen release energy and compressor power consumption obtained in step 6. When the hydrogen release energy + compressor power consumption ≤ the available energy of the hydrogen internal combustion engine waste heat, the energy required by the on-board hydrogen storage module is completely provided by the waste heat recovery module; when the hydrogen release energy + compressor power consumption > the available energy of the hydrogen internal combustion engine waste heat, the energy difference required by the on-board hydrogen storage module is supplemented by the battery; Step 8: Through the energy evaluation of step 7, determine whether the on-board hydrogen storage method can utilize the waste heat energy of the hydrogen internal combustion engine to work. If it can utilize the waste heat energy of the hydrogen internal combustion engine to work, it is determined that the waste heat utilization rate is improved; otherwise, return to step 2.

[0028] Example The present invention is implemented and verified on a 2.0L four-stroke exhaust gas turbocharged hydrogen internal combustion engine, and multiple hydrogen storage methods are evaluated and selected in combination with a hybrid power system.

[0029] When the engine is operated in the hybrid power generation mode with a maximum BTE of 43%, it is calculated that only a hydrogen flow rate of 4.42 kg / h is needed to generate a peak power of 64 kW. At this time, the temperature of the coolant 25 of the hydrogen internal combustion engine 1 is 105°C and the exhaust temperature is 450°C. In addition, the exergy analysis calculation of the waste heat of the hydrogen internal combustion engine 1 is performed, and the calculation results are mentioned below.

[0030] like Figure 4 As shown, when working under this condition, the exhaust gas temperature is between 243 and 450°C, which can meet almost all hydrogen storage methods except NH3. This means that if the temperature provided by the exhaust gas is fully used, the hydrogen storage method using NH3 as the carrier cannot be used.

[0031] The useful energy of the waste heat of the hydrogen internal combustion engine 1 is calculated, and the calculation results are as follows: Figure 5 As shown, after the Rankine cycle waste heat recovery device 27 recovers the waste heat, after the useful energy calculation, it can be obtained that the useful energy of the exhaust gas from the high-temperature heat exchanger 22 accounts for 79%, the useful energy of the waste heat from the intercooler heat exchanger 24 accounts for 7%, and the useful energy of the waste heat from the low-temperature heat exchanger 26 accounts for 14%. The total waste heat useful energy is 22.79kW. The useful energy of H2ICE waste heat can cover MOFs, LT_MH and physical storage methods. However, for hydrogen storage methods such as HT_MH, MBH, LOHC, and NH3, the useful energy of the waste heat of the hydrogen internal combustion engine 1 cannot fully meet the release and compression of hydrogen. In this case, if these hydrogen storage methods are used, the battery 43 needs to provide a certain amount of energy to supplement the useful energy of the waste heat.

[0032] Therefore, under this operating condition, if one wants to fully utilize the waste heat and useful energy of the hydrogen internal combustion engine 1 to store hydrogen, MOFs, LT_MH and physical hydrogen storage methods can be used.

[0033] Therefore, the present invention adopts the above-mentioned long-range commercial vehicle hydrogen internal combustion engine hybrid power system and on-board hydrogen storage method evaluation, based on the energy conservation equation, exergy analysis collaborative analysis method, combined with the hydrogen internal combustion engine hybrid power system, to calculate the waste heat available energy of the hydrogen internal combustion engine, pay attention to the reaction temperature required for various hydrogen storage methods, the required energy required to release hydrogen, and evaluate and select on-board hydrogen storage methods for common working conditions of long-range commercial vehicles, which has good economic benefits and broad application prospects.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A long-range commercial vehicle hydrogen internal combustion engine hybrid power system, characterized by: It includes a hydrogen internal combustion engine, a waste heat recovery module, an on-board hydrogen storage module and a power generation and range extension module, wherein the power output side of the hydrogen internal combustion engine is connected to the input end of the power generation and range extension module, the exhaust end of the hydrogen internal combustion engine is connected to the input end of the waste heat recovery module, the output end of the waste heat recovery module is connected to the input end of the on-board hydrogen storage module, the output end of the on-board hydrogen storage module is connected to the intake end of the hydrogen internal combustion engine, and the output end of the power generation and range extension module is connected to the input end of the on-board hydrogen storage module.

2. The long-range commercial vehicle hydrogen internal combustion engine hybrid power system according to claim 1 is characterized in that: The waste heat recovery module includes a turbine, a low-temperature heat exchanger and a Rankine cycle waste heat recovery device. The input end of the turbine is connected to the exhaust end of the hydrogen internal combustion engine, and the output end of the turbine is respectively connected to the input ends of the high-temperature heat exchanger and the compressor. The output end of the compressor is connected to the input end of the intercooler heat exchanger, and the output end of the intercooler heat exchanger is connected to the intake end of the hydrogen internal combustion engine. A coolant is provided in the hydrogen internal combustion engine, and the coolant enters the low-temperature heat exchanger from the inside of the hydrogen internal combustion engine. The input end of the Rankine cycle waste heat recovery device collects the waste heat generated by the low-temperature heat exchanger, the high-temperature heat exchanger and the intercooler heat exchanger, and the output end of the Rankine cycle waste heat recovery device is connected to the input end of the on-board hydrogen storage module.

3. The long-range commercial vehicle hydrogen internal combustion engine hybrid power system according to claim 2 is characterized in that: The power generation and range extension module includes a generator, a first power converter and a second power converter. The input end of the generator is connected to the hydrogen internal combustion engine, and the output end of the generator is connected to the drive motor. The input end of the first power converter is connected to the generator, and the output end of the first power converter is connected to the input end of the battery. The output end of the battery is respectively connected to the drive motor and the second power converter, and the output end of the second power converter is connected to the on-board hydrogen storage module.

4. An on-board hydrogen storage method evaluation for a long-range commercial vehicle hydrogen internal combustion engine hybrid system as claimed in any one of claims 1 to 3, characterized in that: Step 1: Select an on-board hydrogen storage method to be evaluated and determine the reaction temperature range of the on-board hydrogen storage method; Step 2: According to the driving conditions of different commercial vehicle hybrid systems, the power, effective thermal efficiency and hydrogen calorific value required under the driving conditions are determined to select a hybrid mode; Step 3: Calculate the hydrogen flow rate under the driving condition according to the power, effective thermal efficiency and hydrogen calorific value obtained in step 2; Step 4: Calculate the waste heat available energy according to the energy conservation equation and the exergy equation; Step 5, measuring the high-temperature exhaust gas temperature by a temperature sensor provided at the exhaust outlet of the hydrogen internal combustion engine, judging whether the hydrogen storage method is reasonable according to the high-temperature exhaust gas temperature during the operation of the hydrogen internal combustion engine, and judging that the hydrogen storage method is reasonable when the reaction temperature is ≤ the high-temperature exhaust gas temperature; and reselecting the hydrogen storage method when the reaction temperature is > the high-temperature exhaust gas temperature; Step 6, calculating the hydrogen release energy and compressor power consumption according to the hydrogen storage method selected in step 5; Step 7: Perform energy evaluation based on the hydrogen release energy and compressor power consumption obtained in step 6. When the hydrogen release energy + compressor power consumption ≤ the available energy of the hydrogen internal combustion engine waste heat, the energy required by the on-board hydrogen storage module is completely provided by the waste heat recovery module; when the hydrogen release energy + compressor power consumption > the available energy of the hydrogen internal combustion engine waste heat, the energy difference required by the on-board hydrogen storage module is supplemented by the battery; Step 8: Through the energy evaluation of step 7, determine whether the on-board hydrogen storage method can utilize the waste heat energy of the hydrogen internal combustion engine to work. If it can utilize the waste heat energy of the hydrogen internal combustion engine to work, it is determined that the waste heat utilization rate is improved; otherwise, return to step 2.

5. The on-board hydrogen storage method evaluation of the long-range commercial vehicle hydrogen internal combustion engine hybrid system according to claim 4 is characterized by: The hybrid mode of step 2 includes direct drive of a hydrogen internal combustion engine and battery range extension.

6. The on-board hydrogen storage method evaluation of the long-range commercial vehicle hydrogen internal combustion engine hybrid system according to claim 4 is characterized by: The step 3 calculates the hydrogen flow rate under the driving condition, and the calculation formula is as follows: （1） Where: is power, unit W; is the hydrogen flow rate, in kg / h; M is the calorific value of hydrogen, in MJ / kg; For effective thermal efficiency.

7. The on-board hydrogen storage method evaluation of the long-range commercial vehicle hydrogen internal combustion engine hybrid system according to claim 6 is characterized by: The energy conservation equation of step 4 is as follows: （2） in: The energy brought by hydrogen fuel, The energy brought by the intake air, The work done by a hydrogen internal combustion engine, The energy taken away by the intercooler heat exchanger, The energy taken away by the high-temperature exhaust gas, The energy taken away by the coolant, Loss of energy for others.

8. The on-board hydrogen storage method evaluation of the long-range commercial vehicle hydrogen internal combustion engine hybrid system according to claim 7 is characterized by: The expression for calculating the waste heat available energy by the exergy equation in step 4 is as follows: （3） （4） （5） （6） （7） （8） （9） （10） in, is the available energy in the intake air of a hydrogen internal combustion engine. is the available energy contained in the fuel, is the available energy contained in the exhaust gas, is the available energy contained in the coolant, The work done by a hydrogen internal combustion engine, is the mass flow rate of intake air, is the specific heat capacity of air, is the ambient temperature, is the mass flow rate of hydrogen, is the mass flow rate of exhaust gas, is the specific enthalpy at exhaust temperature and pressure, is the specific enthalpy of ambient temperature and ambient pressure, is the entropy at exhaust temperature and pressure, is the entropy of ambient temperature and ambient pressure, is the utilization rate of available energy in exhaust gas, is the flow rate of coolant, is the temperature of the coolant, is the efficiency of the available energy in the coolant, The available efficiency of hydrogen fuel.

9. The on-board hydrogen storage method evaluation of the long-range commercial vehicle hydrogen internal combustion engine hybrid system according to claim 8 is characterized by: The calculation formula of hydrogen release energy and compressor power consumption in step 6 is as follows: （11） （12） in, is the specific enthalpy of different storage materials at the hydrogen release temperature, is the mass flow rate through the compressor, is the dehydrogenation enthalpy, is the hydrogen mass flow rate, The power required to compress a substance to a pressure, is the flow rate out of the compressor, is the flow rate entering the compressor, The efficiency of the compressor.

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