Fuel cell testing and lithium-ion battery capacity coupling system and method

Abstract

The present invention discloses a fuel cell test and lithium-ion battery capacity-splitting coupling system, including a fuel cell test unit, an energy storage battery, a lithium-ion battery capacity-splitting unit, an energy storage bidirectional inverter, and an energy management unit; the energy management unit is respectively connected to the fuel cell test unit, the energy storage battery, the lithium-ion battery capacity-splitting unit, and the energy storage bidirectional inverter in communication, and the energy storage battery is respectively electrically connected to the fuel cell test unit, the lithium-ion battery capacity-splitting unit, and the energy storage bidirectional inverter; and a control method for the fuel cell test and lithium-ion battery capacity-splitting coupling system is also disclosed. The present invention avoids the energy waste of conventional resistive loads that consume the electric energy generated by the fuel cell system through heat energy, and also saves the extra electric energy consumption for cooling the resistive load.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cell testing, and in particular to a fuel cell testing and lithium ion battery capacity coupling system and method. Background Art

[0002] Large-scale research, verification and testing of fuel cell stacks, fuel cell systems and fuel cell engines are essential steps before the application of fuel cells. Since the fuel cell itself is a power generation device that continuously consumes hydrogen, the first solution in the traditional performance test process is to use a resistive load to consume the electricity generated by the fuel cell system through heat energy, resulting in waste of resources and increased costs. In addition, the commonly used electronic loads also require cooling towers, large fans and even air conditioners to dissipate heat in the process of releasing heat energy to ensure the normal operation of the electronic loads, so additional electricity is required. For fuel cell power systems for new energy vehicles, whose power exceeds 30kW or even up to 100kW, the use of electronic load testing will result in a huge waste of electricity and rising testing costs.

[0003] The second solution is to use a grid-fed electronic load to feed the power output during the fuel cell test back to the grid. Although this solution can effectively avoid the heat consumption of the fuel cell during the test discharge process, due to the complexity and diversity of the test process (such as frequent start-stop loading, acceleration, and testing polarization curves, etc.) and multiple stacks in parallel testing, when feeding power to the grid in this case, it will cause serious high-frequency harmonic interference to the grid, which is difficult to handle, seriously affecting the power quality of the grid and even causing impact on the grid.

[0004] The third solution is to use the electricity output during the fuel cell test to obtain hydrogen through water electrolysis to produce hydrogen and then pass it into the fuel cell for recycling. However, the efficiency of converting hydrogen into electricity during the operation of the fuel cell is generally 50% (based on the low heating value LHV of hydrogen). Although the theoretical electrolysis efficiency of the generated electricity to produce hydrogen through water electrolysis is very high (the apparent conversion efficiency can even reach 100% to 122%), the energy conversion efficiency is only 50% to 70% in industry due to factors such as heating and polarization overpotential required to increase the hydrogen production rate. The efficiency of completing a complete cycle of hydrogen → fuel cell → electrolyzer → hydrogen is only 30%, the energy loss exceeds 70%, the energy utilization rate is extremely low, and the cost of the water electrolysis hydrogen production system (especially the solid electrolyte membrane water electrolysis hydrogen production system using precious metals platinum or iridium as catalysts) is high and the life is short. Therefore, this solution is not economical, and there are problems of complex system and complicated maintenance. Summary of the invention

[0005] In view of the deficiencies in the prior art, the object of the present invention is to provide a fuel cell testing and lithium-ion battery capacity coupling system and method.

[0006] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0007] An embodiment of the present invention provides a fuel cell test and lithium-ion battery capacity-sharing coupling system, which includes a fuel cell test unit, an energy storage battery, a lithium-ion battery capacity-sharing unit, an energy storage bidirectional inverter, and an energy management unit; the energy management unit is respectively communicatively connected to the fuel cell test unit, the energy storage battery, the lithium-ion battery capacity-sharing unit, and the energy storage bidirectional inverter, and the energy storage battery is respectively electrically connected to the fuel cell test unit, the lithium-ion battery capacity-sharing unit, and the energy storage bidirectional inverter.

[0008] In the above scheme, the fuel cell test unit includes at least one group of fuel cell test platforms and unidirectional DC / DC, the DC output end of the fuel cell to be tested in the fuel cell test platform is electrically connected to the input end of the corresponding unidirectional DC / DC, and the output end of the unidirectional DC / DC is electrically connected to an input end of the energy storage battery.

[0009] In the above solution, the energy storage battery includes an energy storage battery group and a battery management unit, and the energy storage battery group is connected to the battery management unit BMS through a low-voltage signal line.

[0010] In the above scheme, the energy storage battery group adopts one or more of lead-acid batteries, lead-carbon batteries, lithium-ion batteries, liquid flow batteries, sodium-sulfur batteries, lithium titanate batteries, and all-vanadium liquid flow batteries.

[0011] In the above scheme, the lithium-ion battery capacity-splitting unit includes at least one group of lithium-ion battery cell capacity-splitting cabinets and a bidirectional DC / DC, the lithium-ion battery cell capacity-splitting cabinet is electrically connected to one end of the corresponding bidirectional DC / DC, and the other end of the bidirectional DC / DC is electrically connected to an input end of the energy storage battery.

[0012] In the above scheme, the energy management unit is connected to the fuel cell test platform and unidirectional DC / DC in the fuel cell test unit, the battery management unit in the energy storage battery, the lithium ion battery cell capacity-splitting cabinet and the bidirectional DC / DC in the lithium ion battery capacity-splitting unit, and the energy storage bidirectional inverter through CAN lines, respectively, and is used to receive real-time parameter information of the fuel cell test unit, the energy storage battery and the lithium ion battery capacity-splitting unit and issue operation instructions to the control elements of the fuel cell test platform, the unidirectional DC / DC, the battery management unit BMS, the lithium ion battery cell capacity-splitting cabinet, the bidirectional DC / DC and the energy storage bidirectional inverter PCS according to preset commands.

[0013] The embodiment of the present invention also provides a control method for a fuel cell test and lithium-ion battery capacity coupling system, which is implemented by the following steps:

[0014] Step (1), the energy management unit starts a self-check and confirms that the grid-connected isolation switch of the energy storage bidirectional inverter is in an off state, so that the fuel cell test and lithium-ion battery capacity coupling system enter an initial off-grid control mode;

[0015] Step (2), the energy management unit obtains the number of fuel cells to be tested in the fuel cell test platform and the test parameters and determines the total amount of electricity Q1 generated by the fuel cell during the entire test process, obtains the SOC of the energy storage battery group through the energy storage battery group and determines the initial charge Q2 of the energy storage battery group and the amount of electricity Q′2 required to charge from the current SOC to the set SOC upper limit, obtains the capacity model (i.e., ampere-hours) and number of lithium-ion battery cells in the lithium-ion battery formation and capacity division cabinet, and calculates the total capacity Q3 of the lithium-ion battery cells that need to be charged during the formation and / or capacity division process; and then compares the sizes of Q1, Q2, Q′2 and Q3:

[0016] If Q1≤Q′2, and Q3≤Q1+Q2, then the steady-state off-grid operation mode is entered;

[0017] If Q1>Q′2, or Q3>Q1+Q2, it enters the transient grid-connected working mode.

[0018] In the above scheme, the steady-state off-grid working mode is: the energy management unit sends a start signal to the fuel cell test platform, performs an electrochemical performance test on the fuel cell to be tested according to preset parameters and steps, and at the same time sends a connection instruction to the unidirectional DC / DC corresponding to the fuel cell test platform to output the electric energy generated by the fuel cell tested online on the fuel cell test platform to the energy storage battery pack after DC / DC voltage conversion; and according to the demand, the energy management unit sends a start signal to the lithium-ion battery capacity-splitting cabinet, charges and discharges the lithium-ion battery cells entering the capacity-splitting process according to the preset step parameter settings and cycle parameter settings, and at the same time gives the lithium-ion battery a start signal. The bidirectional DC / DC corresponding to the battery splitting cabinet sends a connection instruction to realize that the lithium-ion battery cell outputs the electric energy in the energy storage battery group to the lithium-ion battery splitting cabinet after DC / DC voltage conversion to charge the lithium-ion battery cell in the charging step and the lithium-ion battery cell outputs the electric energy stored in the lithium-ion battery cell to the energy storage battery group after DC / DC voltage conversion in the discharging step; in the whole process of fuel cell testing and lithium-ion battery cell splitting, the electric energy generated by the fuel cell is only transmitted between the fuel cell testing platform, the energy storage battery group and the splitting cabinet, and the grid-connected isolation switch of the energy storage bidirectional inverter PCS is always in a disconnected state.

[0019] In the above scheme, if Q3<Q2, the test of the fuel cell and the charging and discharging of the lithium-ion battery cell are in a decoupled state; if Q2≤Q3≤Q1+Q2, the energy management unit EMS adopts a scheduling optimization strategy of delaying the charging step of one or several groups of lithium-ion battery cells of the lithium-ion battery charging and discharging cabinet according to the state of charge SOC of the energy storage battery group monitored in real time.

[0020] In the above scheme, the transient grid-connected working mode is: the energy management unit sends a start signal to the fuel cell test platform, performs an electrochemical performance test on the fuel cell to be tested according to preset parameters and steps, and at the same time sends a connection instruction to the unidirectional DC / DC corresponding to the fuel cell test platform to output the electric energy generated by the fuel cell tested online on the fuel cell test platform to the energy storage battery pack after DC / DC voltage conversion; and according to demand, the energy management unit sends a start signal to the lithium-ion battery capacity-splitting cabinet, charges and discharges the lithium-ion battery cells entering the capacity-splitting process according to preset process step parameter settings and cycle parameter settings, and at the same time sends a connection instruction to the bidirectional DC / DC corresponding to the lithium-ion battery capacity-splitting cabinet to realize that the lithium-ion battery cells in the energy storage battery pack are output to the lithium-ion battery capacity-splitting cabinet after DC / DC voltage conversion to charge the lithium-ion battery cells in the charging process and the lithium-ion battery cells in the discharging process. The electric energy stored in the lithium-ion battery cell is output to the energy storage battery group after DC / DC voltage conversion; during the fuel cell test and the lithium-ion battery cell capacity division process, the energy management unit monitors the state of charge SOC of the energy storage battery group in real time, and sends a grid connection instruction to the energy storage bidirectional inverter when it is monitored that the state of charge SOC of the energy storage battery group exceeds the set SOC upper limit or is lower than the set SOC lower limit; when the state of charge SOC of the energy storage battery group exceeds the set SOC upper limit, the electric energy stored in the energy storage battery group is output to the power grid through the energy storage bidirectional inverter, thereby freeing up storage capacity to continuously receive the electric energy generated by the fuel cell under test or / and the electric energy discharged and fed back to the energy storage battery group by the lithium-ion battery cell; when the state of charge SOC of the energy storage battery group is lower than the set SOC lower limit, the electric energy of the power grid is output to the energy storage battery group through the energy storage bidirectional inverter to supplement the storage capacity to continuously charge the lithium-ion battery cell, thereby ensuring the orderly and smooth operation of the fuel cell test and the lithium-ion battery cell capacity division process.

[0021] In the above scheme, it is characterized in that if Q1>Q′2 and Q3≤Q1+Q2, the energy management unit preferentially adopts a scheduling optimization strategy for delaying the test of one or several groups of fuel cells of the fuel cell test platform to realize the normal power transmission of the entire fuel cell test and lithium-ion battery capacity coupling system. When the above scheduling optimization strategy still cannot guarantee the normal power transmission of the entire coupling system and it is monitored that the state of charge SOC of the energy storage battery group exceeds the set SOC upper limit, a grid connection instruction is sent to the energy storage bidirectional inverter, and the electric energy stored in the energy storage battery group is stably output to the power grid through the energy storage bidirectional inverter, thereby freeing up storage capacity for continuous connection. The electric energy generated by the fuel cell under test or / and the electric energy discharged by the lithium-ion battery cell and fed back to the energy storage battery group; if Q1≤Q′2 and Q3>Q1+Q2, the energy management unit preferentially adopts a scheduling optimization strategy for delaying the charging step of one or several groups of lithium-ion battery cells in the lithium-ion battery cell capacity cabinet to realize the normal power transmission of the entire fuel cell test and lithium-ion battery capacity coupling system. When the above scheduling optimization strategy still cannot guarantee the normal power transmission of the entire coupling system and it is monitored that the state of charge SOC of the energy storage battery group is lower than the set SOC lower limit, a grid connection instruction is sent to the energy storage bidirectional inverter to connect the power of the grid. It can stably output to the energy storage battery group to supplement the storage capacity to continuously charge the lithium-ion battery cells; if Q1>Q′2 and Q3>Q1+Q2, the energy management unit preferentially adopts scheduling optimization strategies such as delaying the test of one or several fuel cells of the fuel cell test platform and / or the charging and discharging of one or several lithium-ion battery cells of the lithium-ion battery cell component cabinet to achieve normal power transmission of the entire fuel cell test and lithium-ion battery component coupling system. When the above scheduling optimization strategy still cannot guarantee the normal power transmission of the entire coupling system and monitors that the state of charge SOC of the energy storage battery group exceeds the set SOC upper limit or is lower than the set SOC When the SOC is below the set SOC lower limit, a grid connection instruction is sent to the energy storage bidirectional inverter. When the state of charge SOC of the energy storage battery group exceeds the set SOC upper limit, the electric energy stored in the energy storage battery group is stably output to the power grid through the energy storage bidirectional inverter, thereby freeing up storage capacity to continuously receive the electric energy generated by the fuel cell under test or / and the electric energy discharged and fed back to the energy storage battery group by the lithium-ion battery cells. When the state of charge SOC of the energy storage battery group is lower than the set SOC lower limit, the electric energy of the grid is stably output to the energy storage battery group through the energy storage bidirectional inverter to supplement the storage capacity to continuously charge the lithium-ion battery cells, thereby ensuring the orderly and smooth operation of the fuel cell test and lithium-ion battery cell capacity division process.

[0022] Compared with the prior art, the present invention uses the electric energy generated during the electrochemical test of the fuel cell for the capacity division of the lithium-ion battery. On the one hand, it avoids the energy waste of the conventional resistive load consuming the electric energy generated by the fuel cell system through heat energy, and also saves the extra electric energy consumption for the resistance load cooling equipment; on the other hand, the use of the energy storage battery pack realizes the closed circulation of electric energy between the energy storage battery pack and the lithium-ion battery under test, thereby avoiding the waste of electric energy of the lithium-ion battery frequently drawing electricity from the power grid for charging during the capacity division and then discharging in the form of resistive heat energy, and the more times of charging and discharging, the greater the waste of electric energy. Therefore, the coupling system of fuel cell testing and lithium-ion battery capacity division provided by the present invention realizes the efficient utilization of electric energy in the fuel cell testing and lithium-ion battery capacity division process, and thus also greatly saves electricity costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The figure is a schematic structural diagram of a fuel cell testing and lithium-ion battery capacity coupling system according to an embodiment of the present invention.

[0024] Figure 2 The present invention is a flow chart of a control method of a fuel cell test and lithium-ion battery capacity coupling system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The embodiments of the present invention are further described below with reference to the accompanying drawings, and the advantages and features of the present invention will become clearer as the description proceeds. However, the embodiments are exemplary only and do not constitute any limitation to the scope of the present invention. It should be understood by those skilled in the art that the details and forms of the technical solutions of the present invention may be modified or replaced without departing from the spirit and scope of the present invention, but these modifications and replacements all fall within the scope of protection of the present invention.

[0026] In addition, in order to better illustrate the present invention, numerous specific details are provided in the following specific embodiments. Those skilled in the art will appreciate that the present invention can be implemented without these specific details. In other embodiments, well-known methods, processes, components and circuits are not described in detail in order to highlight the subject matter of the present invention.

[0027] The embodiment of the present invention provides a fuel cell test and lithium ion battery capacity coupling system, such as Figure 1As shown, it includes a fuel cell test unit 1, an energy storage battery 2, a lithium-ion battery capacity conversion unit 3, an energy storage bidirectional inverter (PCS) 4, and an energy management unit (EMS) 5; the energy management unit 5 is respectively connected to the fuel cell test unit 1, the energy storage battery 2, the lithium-ion battery capacity conversion unit 3, and the energy storage bidirectional inverter 4 for communication, and the energy storage battery 2 is respectively electrically connected to the fuel cell test unit 1, the lithium-ion battery capacity conversion unit 3, and the energy storage bidirectional inverter 4;

[0028] Specifically, the fuel cell test unit 1 includes a fuel cell test platform 11 and a unidirectional DC / DC 12, the DC output end of the fuel cell to be tested in the fuel cell test platform 11 is electrically connected to the corresponding input end of the unidirectional DC / DC 12, and the output end of the unidirectional DC / DC 12 is electrically connected to an input end of the energy storage battery 2.

[0029] The fuel cell test platform 11 in the fuel cell test unit 1 is used to test and evaluate the polarization curve, electrochemical impedance spectroscopy (EIS) and electrochemical performance of the fuel cell under various simulated working conditions, while the unidirectional DC / DC 12 outputs the electric energy generated by the fuel cell during the test to the energy storage battery 2 after voltage conversion.

[0030] Furthermore, the fuel cell test platform 11 in the fuel cell test unit 1 can be a single unit or multiple units to form a fuel cell test platform array, and each of the fuel cell test platforms in the fuel cell test platform array works independently without interfering with each other; and the number of the unidirectional DC / DC 12 is consistent with the number of the fuel cell test platforms 11 and forms a one-to-one correspondence;

[0031] Optionally, the fuel cell test platform 11 includes but is not limited to a hydrogen flow test unit, an air flow test unit, a water management unit, a thermal management unit and a control unit, and the fuel cells tested include but are not limited to fuel cell cells, fuel cell stacks, fuel cell systems, fuel cell engines, etc.; and different fuel cells have different configurations of the corresponding fuel cell test platforms, as long as the type of fuel cell tested and the test parameters match the fuel cell test platform. Similarly, the unidirectional DC / DC 12 corresponding to the fuel cell test platform will also have different configuration parameters due to the different voltages and currents of the fuel cells to be tested, as long as the voltage and current intervals that can be converted match the voltage and current output by the fuel cell. In other words, the fuel cell test platforms 11 in the above-mentioned fuel cell test platform array can be of the same type or of different types; correspondingly, the unidirectional DC / DC 12 can also be of the same type or of different types, but the input configuration parameters of each unidirectional DC / DC must match the electrical output parameters of the fuel cell test platform to which it is connected, and its output configuration parameters must also match the charging parameters of the energy storage battery 2.

[0032] Specifically, the energy storage battery 2 includes an energy storage battery group 21 and a battery management unit BMS22, and the energy storage battery group 21 and the battery management unit BMS22 are connected via a low-voltage signal line.

[0033] The energy storage battery pack 21 is used to receive the DC power generated by the fuel cell during the test process transmitted by the unidirectional DC / DC 12 in the fuel cell test unit 1, and to perform bidirectional power transmission between the lithium-ion battery capacity unit 3 and the power grid;

[0034] Optionally, the energy storage battery group 21 adopts one or more of lead-acid batteries, lead-carbon batteries, lithium-ion batteries, liquid flow batteries, and sodium-sulfur batteries; preferably, the energy storage battery group 21 preferentially adopts lithium titanate batteries or all-vanadium liquid flow batteries.

[0035] The battery management unit BMS22 is used to monitor the voltage, current and temperature of the energy storage battery group 21, accurately estimate the state of charge SOC of the energy storage battery group 21 and transmit the real-time collected data information to the energy management unit 5 through the CAN line, and at the same time perform energy balancing between the single cells of the energy storage battery group 21.

[0036] Specifically, the lithium-ion battery cell capacity unit 3 includes a lithium-ion battery cell capacity cabinet 31 and a bidirectional DC / DC 32. The lithium-ion battery cell capacity cabinet 31 is electrically connected to one end of the corresponding bidirectional DC / DC 32, and the other end of the bidirectional DC / DC 32 is electrically connected to an input end of the energy storage battery 2.

[0037] The lithium-ion battery cell capacity splitting cabinet 31 in the lithium-ion battery capacity splitting unit 3 is used to charge and discharge the lithium-ion battery cells entering the capacity splitting process through bidirectional energy transfer with the energy storage battery 2; the bidirectional DC / DC 32 is used to realize bidirectional energy transfer between the energy storage battery 2 and the lithium-ion battery cell capacity splitting cabinet 31 through DC voltage conversion, and the number of the bidirectional DC / DC 32 is consistent with the number of the lithium-ion battery cell capacity splitting cabinets 31 and forms a one-to-one correspondence.

[0038] Furthermore, the lithium-ion battery cell storage cabinet 31 may be a single unit or a plurality of units to form a lithium-ion battery cell storage cabinet array; moreover, each of the lithium-ion battery cell storage cabinets 31 in the lithium-ion battery cell storage cabinet array operates independently without interfering with each other.

[0039] Optionally, in the above-mentioned lithium-ion battery cell capacity splitting cabinet array, depending on the type and capacity (ampere-hours) of the lithium-ion battery cells entering the capacity splitting process, the specific parameter configuration of the corresponding lithium-ion battery cell capacity splitting cabinet 31 is also different, as long as its configuration matches the process step parameters of the lithium-ion battery cells that need to be split; similarly, the bidirectional DC / DC 32 corresponding to the lithium-ion battery cell capacity splitting cabinet 31 will also have different configuration parameters due to the different voltages and currents of the lithium-ion battery cells that need to be split, as long as the voltage and current range that it can convert matches the voltage and current of the lithium-ion battery cells for charging and discharging. In other words, the lithium-ion battery cell capacity cabinets 31 in the above-mentioned lithium-ion battery cell capacity cabinet array can be of the same type or of different types; correspondingly, the bidirectional DC / DC 32 can also be of the same type or of different types, but the configuration parameters at both ends of each bidirectional DC / DC 32 must respectively match the input and output parameters of the lithium-ion battery cell capacity cabinet to which it is connected and the charge and discharge parameters of the energy storage battery 2.

[0040] Specifically, the DC end of the energy storage bidirectional inverter 4 is electrically connected to the energy storage battery 2, and the AC end thereof is electrically connected to the power grid, so as to realize bidirectional energy transfer between the energy storage battery group and the AC power grid through AC / DC conversion under specific circumstances.

[0041] Specifically, the energy management unit 5 is connected to the fuel cell test platform 11 and the unidirectional DC / DC 12 in the fuel cell test unit 1, the battery management unit BMS22 in the energy storage battery 2, the lithium ion battery cell capacity-splitting cabinet 31 and the bidirectional DC / DC 32 in the lithium ion battery capacity-splitting unit 3, and the energy storage bidirectional inverter 4 through CAN lines, respectively, and is used to receive real-time parameter information of the fuel cell test unit 1, the energy storage battery 2 and the lithium ion battery capacity-splitting unit 3 and issue operation instructions to the control elements of the fuel cell test platform 11, the unidirectional DC / DC 12, the battery management unit BMS22, the lithium ion battery cell capacity-splitting cabinet 31, the bidirectional DC / DC 32 and the energy storage bidirectional inverter 4 according to preset commands, so as to manage and schedule the energy of the entire fuel cell test and lithium ion battery capacity-splitting coupling system to maintain the normal operation of the entire system.

[0042] The energy management unit 5 operates in a steady-state off-grid operating mode and a transient grid-connected operating mode:

[0043] In the steady-state off-grid working mode, the energy management unit 5 sends a start signal to the fuel cell test platform 11 in the fuel cell test unit 1, and performs an electrochemical performance test on the fuel cell to be tested according to the preset parameters and steps. At the same time, a connection instruction is sent to the unidirectional DC / DC 12 corresponding to the fuel cell test platform 11 to output the electric energy generated by the fuel cell tested online on the fuel cell test platform 11 to the energy storage battery group 21 in the energy storage battery 2 after DC / DC voltage conversion; and according to the demand, the energy management unit 5 supplies the lithium ion battery cell in the lithium ion battery capacity unit 3 with the electric energy generated by the fuel cell tested online. The capacity dividing cabinet 31 sends a start signal, and charges and discharges the lithium-ion battery cells entering the capacity dividing process according to the preset process step parameters and cycle parameters, and at the same time sends a connection instruction to the bidirectional DC / DC 32 corresponding to the lithium-ion battery cell capacity dividing cabinet 31 to realize that the lithium-ion battery cells output the electric energy in the energy storage battery group 21 to the lithium-ion battery cell capacity dividing cabinet 31 after DC / DC voltage conversion in the charging process to charge the lithium-ion battery cells, and the lithium-ion battery cells output the electric energy stored in the lithium-ion battery cells to the energy storage battery group 21 after DC / DC voltage conversion in the discharging process. In the whole process of fuel cell testing and lithium-ion battery cell capacity dividing, the electric energy generated by the fuel cell is only transmitted between the fuel cell testing unit 1, the energy storage battery 2 and the lithium-ion battery capacity dividing unit 3, and the grid-connected isolation switch of the energy storage bidirectional inverter 4 is always in a disconnected state.

[0044] In the transient grid-connected working mode, the energy management unit 5 sends a start signal to the fuel cell test platform 11 in the fuel cell test unit 1, and performs an electrochemical performance test on the fuel cell to be tested according to the preset parameters and steps. At the same time, a connection instruction is sent to the unidirectional DC / DC 12 corresponding to the fuel cell test platform 11 to output the electric energy generated by the fuel cell tested online on the fuel cell test platform 11 to the energy storage battery group 21 in the energy storage battery 2 after DC / DC voltage conversion; and according to the demand, the energy management unit 5 sends the lithium ion battery cell in the lithium ion battery capacity unit 3 to the lithium ion battery cell ... The capacity dividing cabinet 31 sends a start signal to charge and discharge the lithium-ion battery cells entering the capacity dividing process according to the preset process step parameters and cycle parameters, and at the same time sends a connection instruction to the bidirectional DC / DC 32 corresponding to the lithium-ion battery cell capacity dividing cabinet 31 to enable the lithium-ion battery cells to convert the electric energy in the energy storage battery group 21 into DC / DC voltage and output it to the lithium-ion battery cell capacity dividing cabinet 31 to charge the lithium-ion battery cells in the charging process step, and the lithium-ion battery cells to convert the electric energy stored in the lithium-ion battery cells into DC / DC voltage and output it to the energy storage battery group 21 in the discharging process step.

[0045] During this time, the energy management unit 5 monitors the state of charge SOC of the energy storage battery group 21 in real time, and preferentially adopts the scheduling optimization strategies such as delaying the test of one or several groups of fuel cells of the fuel cell test platform 11 and / or the charging and discharging of one or several groups of lithium-ion battery cells of the lithium-ion battery cell sub-capacity cabinet 31 to realize the normal power transmission of the entire fuel cell test and lithium-ion battery sub-capacity coupling system. When the above scheduling optimization strategy still cannot guarantee the normal power transmission of the entire coupling system and it is detected that the state of charge SOC of the energy storage battery group 21 exceeds the set SOC upper limit or is lower than the set SOC lower limit, a grid connection instruction is sent to the energy storage bidirectional inverter 4, and the energy storage bidirectional inverter 4 starts to track the grid side phase. When the phase tracking is completed, the grid connection closing command is immediately issued, and the corresponding execution switch is closed to complete the grid connection; when the state of charge SOC of the energy storage battery group 21 exceeds the set SOC upper limit, the electric energy stored in the energy storage battery group 21 is adjusted to the grid voltage through the energy storage bidirectional inverter 4 through DC / AC inversion. After matching the voltage amplitude, frequency and phase, it is stably output to the power grid to free up storage capacity to continuously receive the electric energy generated by the fuel cell under test and / or the electric energy discharged by the lithium-ion battery cell and fed back to the energy storage battery group 21. When the state of charge SOC of the energy storage battery group 21 is lower than the set SOC lower limit, the electric energy of the power grid is adjusted to a DC voltage matching the charging voltage of the energy storage battery group 21 through AC / DC inversion by the energy storage bidirectional inverter 4, and then stably output to the energy storage battery group 21 to supplement the storage capacity to continuously charge the lithium-ion battery cell, thereby ensuring the orderly and smooth operation of the fuel cell test and lithium-ion battery cell capacity division process.

[0046] The present invention uses the electric energy generated during the electrochemical test of the fuel cell for the capacity division of the lithium-ion battery. On the one hand, it avoids the energy waste of the conventional resistive load consuming the electric energy generated by the fuel cell system through heat energy, and also saves the extra electric energy consumption for the resistance load cooling equipment; on the other hand, the use of the energy storage battery pack realizes the closed circulation of electric energy between the energy storage battery pack and the lithium-ion battery under test, thereby avoiding the waste of electric energy of the lithium-ion battery frequently drawing electricity from the power grid for charging during the capacity division and then discharging in the form of resistance heat energy, and the more times of charging and discharging, the greater the waste of electric energy. Therefore, the coupling system of fuel cell testing and lithium-ion battery capacity division provided by the present invention realizes the efficient utilization of electric energy in the fuel cell testing and lithium-ion battery capacity division process, and thus also greatly saves electricity costs.

[0047] In addition, when power needs to be supplied to the grid in extreme cases, the coupling system provided by the present invention can avoid the serious interference of the high-frequency harmonics of the grid by the usual grid-fed electronic loads due to the use of energy storage battery packs, thereby ensuring the power quality of the grid; on the other hand, it can also achieve peak shaving and valley filling, harmonic control and reactive power compensation for the grid, thereby improving the power quality of the grid; at the same time, the use of energy storage battery packs can also bring additional benefits to enterprises through power auxiliary services such as valley power consumption, peak shaving and frequency regulation.

[0048] The embodiment of the present invention also provides a method for controlling a fuel cell test and lithium-ion battery capacity coupling system. Figure 2 As shown, the method is implemented by the following steps:

[0049] In step 200, the energy management unit 5 starts self-test and confirms that the grid-connected isolating switch of the energy storage bidirectional inverter 4 is in the disconnected state, so that the fuel cell test and lithium-ion battery capacity coupling system enters the initial off-grid control mode. Then, step 201 is entered.

[0050] In step 201, the energy management unit 5 obtains the number of fuel cells to be tested in the fuel cell test unit 1 and the test parameters to calculate the total power Q1 generated by the fuel cell during the entire test process, obtains the SOC of the energy storage battery group 21 through the battery management unit BMS22 in the energy storage battery 2 to calculate the initial charge Q2 of the energy storage battery group 21 and the power Q′2 required to charge from the current SOC to the set SOC upper limit, obtains the capacity model (i.e., ampere-hours) and number of lithium-ion battery cells in the lithium-ion battery formation and capacity division unit 3 to calculate the total capacity Q3 of the lithium-ion battery cells that need to be charged during the formation and / or capacity division process; then compares the sizes of Q1, Q2, Q′2 and Q3 and enters step 202.

[0051] In step 202, when the energy management unit 5 detects that Q1≤Q′2 and Q3≤Q1+Q2, it enters step 210, that is, enters the steady-state off-grid working mode; when it detects that Q1>Q′2 or Q3>Q1+Q2, it enters step 220, that is, enters the transient grid-connected working mode.

[0052] In step 210, the energy management unit 5 sends a start signal to the fuel cell test platform 11 in the fuel cell test unit 1, performs an electrochemical performance test on the fuel cell to be tested according to preset parameters and steps, and sends a connection instruction to the unidirectional DC / DC 12 corresponding to the fuel cell test platform 11 to output the electric energy generated by the fuel cell under online test on the fuel cell test platform 11 to the energy storage battery group 21 in the energy storage battery 2 after DC / DC voltage conversion; and according to the demand, the energy management unit 5 converts the lithium ion battery cells in the lithium ion battery capacity conversion unit 3 into lithium ion battery cells. The cabinet 31 sends a start signal, and charges and discharges the lithium-ion battery cells that have entered the capacity splitting process according to the preset process step parameters and cycle parameters, and at the same time sends a connection instruction to the bidirectional DC / DC 32 corresponding to the lithium-ion battery cell capacity splitting cabinet 31 to realize that the lithium-ion battery cells output the electric energy in the energy storage battery group 21 to the lithium-ion battery cell capacity splitting cabinet 31 after DC / DC voltage conversion in the charging process to charge the lithium-ion battery cells, and the lithium-ion battery cells output the electric energy stored in the lithium-ion battery cells to the energy storage battery group 21 after DC / DC voltage conversion in the discharging process. In the whole process of fuel cell testing and lithium-ion battery cell capacity splitting, the electric energy generated by the fuel cell is only transmitted between the fuel cell testing unit 1, the energy storage battery 2 and the lithium-ion battery capacity splitting unit 3, and the grid-connected isolation switch of the energy storage bidirectional inverter 4 is always in a disconnected state.

[0053] At the same time, the energy management unit 5 compares the magnitudes of Q3 and Q2 and enters step 211 .

[0054] In step 211 , the energy management unit 5 starts to detect whether Q3 is less than Q2 : if so, it goes to step 212 ; if not, it goes to step 213 .

[0055] In step 212, the test of the fuel cell and the chemical composition and capacity determination of the lithium-ion battery cell are in a decoupled state, and can be performed synchronously or in different time periods without interfering with each other.

[0056] In step 213 , the energy management unit 5 starts to detect whether the situation of Q2≤Q3≤Q1+Q2 exists: if so, it goes to step 214 ; if not, it returns to step 211 .

[0057] In step 214, the energy management unit 5 monitors the state of charge SOC of the energy storage battery group 21 in real time. If it is detected that the SOC is close to the preset SOC lower limit, a scheduling optimization strategy is adopted to perform appropriate delay operation on the charging step of one or several groups of lithium-ion battery cells in the lithium-ion battery charging cabinet to achieve normal power transmission of the entire fuel cell test and lithium-ion battery charging coupling system.

[0058] In step 220, the energy management unit 5 sends a start signal to the fuel cell test platform 11 in the fuel cell test unit 1, performs an electrochemical performance test on the fuel cell to be tested according to preset parameters and steps, and sends a connection instruction to the unidirectional DC / DC 12 corresponding to the fuel cell test platform 11 to output the electric energy generated by the fuel cell under online test on the fuel cell test platform 11 to the energy storage battery group 21 in the energy storage battery 2 after DC / DC voltage conversion; and according to the demand, the energy management unit 5 converts the lithium ion battery cells in the lithium ion battery capacity conversion unit 3 into lithium ion battery cells. The cabinet 31 sends a start signal to charge and discharge the lithium-ion battery cells that have entered the capacity splitting process according to the preset process step parameters and cycle parameters, and at the same time sends a connection instruction to the bidirectional DC / DC 32 corresponding to the lithium-ion battery cell capacity splitting cabinet 31 to enable the lithium-ion battery cells to convert the electric energy in the energy storage battery group 21 into DC / DC voltage and output it to the lithium-ion battery cell capacity splitting cabinet 31 to charge the lithium-ion battery cells in the charging process step, and the lithium-ion battery cells to convert the electric energy stored in the lithium-ion battery cells into DC / DC voltage and output it to the energy storage battery group 21 in the discharging process step.

[0059] At the same time, the energy management unit 5 starts to search for existing combinations between Q1 and Q′2 and between Q3 and Q1+Q2 under the premise of Q1>Q′2 or Q3>Q1+Q2, and enters step 221.

[0060] In step 221 , the energy management unit 5 starts to detect whether the situation of Q1>Q′2 and Q3≤Q1+Q2 exists: if so, it goes to step 222 ; if not, it goes to step 223 .

[0061] In step 222, the energy management unit 5 monitors the state of charge SOC of the energy storage battery group 21 in real time, and preferentially adopts a scheduling optimization strategy for delaying the test of one or several groups of fuel cells on the fuel cell test platform 11 to achieve normal power transfer of the entire fuel cell test and lithium-ion battery capacity coupling system. When the above-mentioned scheduling optimization strategy still cannot guarantee the normal power transmission of the entire coupling system and it is monitored that the charge state SOC of the energy storage battery group 21 exceeds the set SOC upper limit, a grid connection instruction is sent to the energy storage bidirectional inverter 4, and the energy storage bidirectional inverter 4 starts to track the grid side phase. When the phase tracking is completed, a grid connection closing command is immediately issued, and the corresponding execution switch is closed to complete the grid connection. The electric energy stored in the energy storage battery group 21 is adjusted to a voltage amplitude, frequency and phase matching the grid voltage through the energy storage bidirectional inverter 4 through DC / AC inversion, and then stably output to the grid, thereby freeing up storage capacity to continuously receive the electric energy generated by the fuel cell under test or / and the electric energy discharged by the lithium-ion battery cell and fed back to the energy storage battery group 21, thereby ensuring the orderly and smooth operation of the fuel cell test and lithium-ion battery cell capacity division process.

[0062] In step 223 , the energy management unit 5 starts to detect whether the situation of Q1≤Q′2 and Q3>Q1+Q2 exists: if so, it goes to step 224 ; if not, it goes to step 225 .

[0063] In step 224, the energy management unit 5 monitors the state of charge SOC of the energy storage battery group 21 in real time, and preferentially adopts a scheduling optimization strategy of delaying the charging step of one or several groups of lithium-ion battery cells in the lithium-ion battery cell capacity-splitting cabinet 31 to achieve normal power transmission of the entire fuel cell test and lithium-ion battery capacity-splitting coupling system. When the above-mentioned scheduling optimization strategy still cannot guarantee the normal power transmission of the entire coupling system and the charge state SOC of the energy storage battery group 21 is monitored to be lower than the set SOC lower limit, a grid connection instruction is sent to the energy storage bidirectional inverter 4, and the energy storage bidirectional inverter 4 starts to track the grid side phase. When the phase tracking is completed, a grid connection closing command is immediately issued, and the corresponding execution switch is closed to complete the grid connection. The power of the grid is adjusted to a DC voltage matching the charging voltage of the energy storage battery group 21 through AC / DC inversion by the energy storage bidirectional inverter 4, and then stably output to the energy storage battery group 21 to supplement the storage capacity to continuously charge the lithium-ion battery cells, thereby ensuring the orderly and smooth operation of the fuel cell test and lithium-ion battery cell capacity conversion process.

[0064] In step 225 , the energy management unit 5 starts to detect whether the situation of Q1>Q′2 and Q3>Q1+Q2 exists: if so, it goes to step 226 ; if not, it returns to step 221 .

[0065] In step 226, the energy management unit 5 monitors the state of charge SOC of the energy storage battery group 21 in real time, and preferentially adopts the scheduling optimization strategy such as delaying the test of one or several groups of fuel cells of the fuel cell test platform 11 and / or the charging and discharging of one or several groups of lithium-ion battery cells of the lithium-ion battery cell sub-capacity cabinet 31 to realize the normal power transmission of the entire fuel cell test and lithium-ion battery sub-capacity coupling system. When the above scheduling optimization strategy still cannot guarantee the normal power transmission of the entire coupling system and it is monitored that the state of charge SOC of the energy storage battery group 21 exceeds the set SOC upper limit or is lower than the set SOC lower limit, a grid connection instruction is sent to the energy storage bidirectional inverter 4, and the energy storage bidirectional inverter 4 starts to track the grid side phase. When the phase tracking is completed, the grid connection closing command is immediately issued, and the corresponding execution switch is closed to complete the grid connection; when the state of charge SOC of the energy storage battery group 21 exceeds the set SOC upper limit, the electric energy stored in the energy storage battery group 21 is adjusted to the grid voltage through the energy storage bidirectional inverter 4 through DC / AC inversion. After matching the voltage amplitude, frequency and phase, it is stably output to the power grid to free up storage capacity to continuously receive the electric energy generated by the fuel cell under test and / or the electric energy discharged by the lithium-ion battery cell and fed back to the energy storage battery group 21. When the state of charge SOC of the energy storage battery group 21 is lower than the set SOC lower limit, the electric energy of the power grid is adjusted to a DC voltage matching the charging voltage of the energy storage battery group 21 through AC / DC inversion by the energy storage bidirectional inverter 4, and then stably output to the energy storage battery group 21 to supplement the storage capacity to continuously charge the lithium-ion battery cell, thereby ensuring the orderly and smooth operation of the fuel cell test and lithium-ion battery cell capacity division process.

[0066] The embodiments of the present invention are disclosed as above, however, the embodiments are not intended to limit the scope of the present invention. Simple equivalent changes and modifications made according to the claims and description of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A fuel cell testing and lithium-ion battery capacity coupling system, characterized in that: It includes a fuel cell test unit, an energy storage battery, a lithium-ion battery capacity-splitting unit, an energy storage bidirectional inverter, and an energy management unit; the energy management unit is respectively connected to the fuel cell test unit, the energy storage battery, the lithium-ion battery capacity-splitting unit, and the energy storage bidirectional inverter in communication, and the energy storage battery is respectively electrically connected to the fuel cell test unit, the lithium-ion battery capacity-splitting unit, and the energy storage bidirectional inverter; the fuel cell test unit includes at least one group of fuel cell test platforms and a unidirectional DC / DC, the DC output end of the fuel cell to be tested in the fuel cell test platform is electrically connected to the corresponding input end of the unidirectional DC / DC, and the output end of the unidirectional DC / DC is electrically connected to an input end of the energy storage battery; the fuel cell test platform in the fuel cell test unit is used to test and evaluate the polarization curve, electrochemical impedance spectrum, and electrochemical performance under various simulated working conditions of the fuel cell, and the unidirectional DC / DC outputs the electric energy generated by the fuel cell during the test to the energy storage battery after voltage conversion.

2. The fuel cell testing and lithium-ion battery capacity coupling system according to claim 1 is characterized in that: The energy storage battery comprises an energy storage battery pack and a battery management unit, and the energy storage battery pack is connected to the battery management unit BMS via a low-voltage signal line.

3. The fuel cell testing and lithium-ion battery capacity coupling system according to claim 2 is characterized in that: The energy storage battery group adopts one or more of lead-acid batteries, lead-carbon batteries, lithium-ion batteries, liquid flow batteries, sodium-sulfur batteries, lithium titanate batteries, and all-vanadium liquid flow batteries.

4. The fuel cell testing and lithium-ion battery capacity coupling system according to claim 3 is characterized in that: The lithium-ion battery capacity-splitting unit comprises at least one group of lithium-ion battery cell capacity-splitting cabinets and a bidirectional DC / DC, wherein the lithium-ion battery cell capacity-splitting cabinet is electrically connected to one end of the corresponding bidirectional DC / DC, and the other end of the bidirectional DC / DC is electrically connected to an input end of the energy storage battery.

5. The fuel cell testing and lithium-ion battery capacity coupling system according to claim 4, characterized in that: The energy management unit is connected to the fuel cell test platform and unidirectional DC / DC in the fuel cell test unit, the battery management unit in the energy storage battery, the lithium ion battery cell capacity-splitting cabinet and the bidirectional DC / DC in the lithium ion battery capacity-splitting unit, and the energy storage bidirectional inverter through CAN lines, respectively, and is used to receive real-time parameter information of the fuel cell test unit, the energy storage battery and the lithium ion battery capacity-splitting unit and issue operation instructions to the control elements of the fuel cell test platform, the unidirectional DC / DC, the battery management unit BMS, the lithium ion battery cell capacity-splitting cabinet, the bidirectional DC / DC and the energy storage bidirectional inverter PCS according to preset commands.

6. A control method for a fuel cell test and lithium-ion battery capacity coupling system, characterized in that: This method is implemented through the following steps: Step (1), the energy management unit starts self-test and confirms that the grid-connected isolation switch of the energy storage bidirectional inverter is in the disconnected state, so that the fuel cell test and lithium-ion battery capacity coupling system enter the initial off-grid control mode; Step (2), the energy management unit obtains the number of fuel cells to be tested in the fuel cell test platform and the test parameters and determines the total power Q1 generated by the fuel cell during the entire test process, obtains the SOC of the energy storage battery group through the energy storage battery group and determines the initial charge Q2 of the energy storage battery group and the power Q2 required to charge from the current SOC to the set SOC upper limit ′ 2. Obtain the capacity model and number of lithium-ion battery cells in the lithium-ion battery formation and capacity division cabinet, so as to calculate the total capacity Q3 of the lithium-ion battery cells that need to be charged during the formation and / or capacity division process, wherein the capacity model is ampere-hours; then compare the sizes of Q1, Q2, Q′2 and Q3: If Q1≤Q′2, and Q3≤Q1+Q2, then the steady-state off-grid operation mode is entered; If Q1>Q′2, or Q3>Q1+Q2, it enters the transient grid-connected working mode.

7. The control method of the fuel cell test and lithium-ion battery capacity coupling system according to claim 6, characterized in that: The steady-state off-grid working mode is: the energy management unit sends a start signal to the fuel cell test platform, performs an electrochemical performance test on the fuel cell to be tested according to preset parameters and steps, and at the same time sends a connection instruction to the unidirectional DC / DC corresponding to the fuel cell test platform to output the electric energy generated by the fuel cell tested online on the fuel cell test platform to the energy storage battery group after DC / DC voltage conversion; And according to the demand, the energy management unit sends a start signal to the lithium-ion battery capacity splitting cabinet, charges and discharges the lithium-ion battery cells entering the capacity splitting process according to the preset process step parameter settings and cycle parameter settings, and sends a connection instruction to the bidirectional DC / DC corresponding to the lithium-ion battery capacity splitting cabinet to realize that the lithium-ion battery cells convert the electric energy in the energy storage battery group to the lithium-ion battery capacity splitting cabinet after DC / DC voltage conversion in the charging process to charge the lithium-ion battery cells and the lithium-ion battery cells convert the electric energy stored in the lithium-ion battery cells to the energy storage battery group after DC / DC voltage conversion in the discharging process; in the whole process of fuel cell testing and lithium-ion battery cell capacity splitting, the electric energy generated by the fuel cell is only transmitted between the fuel cell testing platform, the energy storage battery group and the capacity splitting cabinet, and the grid-connected isolation switch of the energy storage bidirectional inverter PCS is always in a disconnected state.

8. The control method of the fuel cell test and lithium-ion battery capacity coupling system according to claim 7, characterized in that: If Q3<Q2, the test of the fuel cell and the charging and discharging of the lithium-ion battery cell are in a decoupled state; if Q2≤Q3≤Q1+Q2, the energy management unit EMS adopts a scheduling optimization strategy for delaying the charging step of one or several groups of lithium-ion battery cells in the lithium-ion battery charging and discharging cabinet according to the state of charge SOC of the energy storage battery group monitored in real time.

9. The control method of the fuel cell test and lithium-ion battery capacity coupling system according to claim 6, characterized in that: The transient grid-connected working mode is: the energy management unit sends a start signal to the fuel cell test platform, performs an electrochemical performance test on the fuel cell to be tested according to preset parameters and steps, and at the same time sends a connection instruction to the unidirectional DC / DC corresponding to the fuel cell test platform to output the electric energy generated by the fuel cell tested online on the fuel cell test platform to the energy storage battery group after DC / DC voltage conversion; And according to the demand, the energy management unit sends a start signal to the lithium-ion battery capacity-splitting cabinet, charges and discharges the lithium-ion battery cells entering the capacity-splitting process according to the preset process step parameter settings and cycle parameter settings, and at the same time sends a connection instruction to the bidirectional DC / DC corresponding to the lithium-ion battery capacity-splitting cabinet to realize that the lithium-ion battery cells in the charging process convert the electric energy in the energy storage battery pack into the lithium-ion battery capacity-splitting cabinet after DC / DC voltage conversion to charge the lithium-ion battery cells and the lithium-ion battery cells in the discharging process convert the electric energy stored in the lithium-ion battery cells into the energy storage battery pack after DC / DC voltage conversion; during the fuel cell test and lithium-ion battery cell capacity-splitting process, the energy management unit monitors the energy storage battery in real time. The state of charge SOC of the energy storage battery group is monitored. When it is monitored that the state of charge SOC of the energy storage battery group exceeds the set SOC upper limit or is lower than the set SOC lower limit, a grid connection instruction is sent to the energy storage bidirectional inverter. When the state of charge SOC of the energy storage battery group exceeds the set SOC upper limit, the electric energy stored in the energy storage battery group is output to the grid through the energy storage bidirectional inverter, thereby freeing up storage capacity to continuously receive the electric energy generated by the fuel cell under test or / and the electric energy discharged and fed back to the energy storage battery group by the lithium-ion battery cell. When the state of charge SOC of the energy storage battery group is lower than the set SOC lower limit, the electric energy of the grid is output to the energy storage battery group through the energy storage bidirectional inverter to supplement the storage capacity to continuously charge the lithium-ion battery cell, thereby ensuring the orderly and smooth operation of the fuel cell test and the lithium-ion battery cell capacity division process.

10. The control method of the fuel cell test and lithium-ion battery capacity coupling system according to claim 9, characterized in that: If Q1>Q′2 and Q3≤Q1+Q2, the energy management unit preferentially adopts a scheduling optimization strategy for delaying the test of one or several fuel cells of the fuel cell test platform to achieve normal power transmission of the entire fuel cell test and lithium-ion battery capacity coupling system. When the above scheduling optimization strategy still cannot guarantee the normal power transmission of the entire coupling system and the state of charge SOC of the energy storage battery group is monitored to exceed the set SOC upper limit, a grid connection instruction is sent to the energy storage bidirectional inverter to stably output the power stored in the energy storage battery group to the power grid through the energy storage bidirectional inverter, thereby freeing up storage capacity to continuously receive the power generated by the fuel cell under test. The generated electric energy or / and the electric energy discharged by the lithium-ion battery cells are fed back to the energy storage battery group; if Q1≤Q′2 and Q3>Q1+Q2, the energy management unit preferentially adopts a scheduling optimization strategy for delaying the charging step of one or several groups of lithium-ion battery cells in the lithium-ion battery cell capacity-forming cabinet to realize the normal power transmission of the entire fuel cell test and lithium-ion battery capacity-forming coupling system. When the above scheduling optimization strategy still cannot guarantee the normal power transmission of the entire coupling system and it is monitored that the state of charge SOC of the energy storage battery group is lower than the set SOC lower limit, a grid connection instruction is sent to the energy storage bidirectional inverter to stably output the power of the power grid to the The energy storage battery pack replenishes the storage capacity to continuously charge the lithium-ion battery cells; if Q1>Q′2 and Q3>Q1+Q2, the energy management unit preferentially adopts scheduling optimization strategies such as delaying the test of one or several fuel cells of the fuel cell test platform and / or the charging and discharging of one or several lithium-ion battery cells of the lithium-ion battery cell component cabinet to achieve normal power transmission of the entire fuel cell test and lithium-ion battery component coupling system. When the above scheduling optimization strategy still cannot guarantee the normal power transmission of the entire coupling system and monitors that the state of charge SOC of the energy storage battery pack exceeds the set SOC upper limit or is lower than the set SOC When the SOC of the energy storage battery group exceeds the set SOC upper limit, the grid connection instruction is sent to the energy storage bidirectional inverter. When the state of charge SOC of the energy storage battery group exceeds the set SOC upper limit, the electric energy stored in the energy storage battery group is stably output to the power grid through the energy storage bidirectional inverter, thereby freeing up storage capacity to continuously receive the electric energy generated by the fuel cell under test or / and the electric energy discharged and fed back to the energy storage battery group by the lithium-ion battery cell. When the state of charge SOC of the energy storage battery group is lower than the set SOC lower limit, the electric energy of the grid is stably output to the energy storage battery group through the energy storage bidirectional inverter to supplement the storage capacity to continuously charge the lithium-ion battery cell, thereby ensuring the orderly and smooth operation of the fuel cell test and the lithium-ion battery cell capacity division process.

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