An energy management device and method for an autonomous power supply type hydrogen fuel cell test bench

Abstract

The present invention discloses an energy management device and method for an independently powered hydrogen fuel cell test bench, which relates to the technical field of fuel cell system testing. The hydrogen fuel cell system to be tested is sequentially connected to an energy feedback electronic load through a series-connected relay K1 and relay K2. The auxiliary equipment of the system to be tested is sequentially connected to an energy storage battery through a series-connected relay K5 and relay K4. The energy feedback electronic load is also connected in parallel with a super capacitor. The super capacitor, the energy feedback electronic load, and the energy storage battery are all connected in parallel. A current sensor A2 and a resistor R are sequentially connected in series between the hydrogen fuel cell system to be tested and the super capacitor, and a relay K3 is connected in parallel with the resistor. The technical solution in this application can prevent the electronic load from continuing to execute the planned test load current when the hydrogen fuel cell system to be tested suddenly fails and shuts down, and avoid damaging the energy storage battery under the condition of excessive current discharge.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cell system testing, and in particular to an energy management device and method for an autonomously powered hydrogen fuel cell test bench. Background Art

[0002] As the global demand for low-carbon energy solutions grows, hydrogen fuel cells are seen as an ideal alternative to traditional fossil fuels due to their zero emissions, high efficiency, and rapid replenishment. Test benches play a vital role in the research, development, and industrialization of hydrogen fuel cell technology. With the continuous advancement of hydrogen fuel cell technology, the performance requirements of its test platform are also continuously upgraded. Traditional test methods rely on additional high-voltage direct current (HVDC) and low-voltage direct current (LVDC) power supplies to drive auxiliary equipment such as air compressors and water pumps when starting hydrogen fuel cell systems, which not only increases operating costs, but also increases the complexity of test environment construction.

[0003] During actual testing and use, the hydrogen fuel cell system may suddenly fail and shut down. At this time, since the energy feedback electronic load is still maintaining the power at the previous moment, the hydrogen fuel cell system under test will immediately stop generating electricity when it fails and the energy storage battery needs to release electrical energy instantly to balance the energy consumption of the electronic load. When the hydrogen fuel cell system under test encounters a sudden failure and shuts down when the power is very high during the test, the energy storage battery will be instantly over-discharged beyond the limit of the energy storage battery, causing battery damage. Therefore, there is an urgent need to solve the battery protection problem caused by sudden failure and shutdown of the hydrogen fuel cell system. The present application proposes an energy management device and method for an autonomously powered hydrogen fuel cell test bench. Summary of the invention

[0004] In view of the defects existing in the prior art, the purpose of the present invention is to provide an energy management device and method for an autonomously powered hydrogen fuel cell test bench, aiming to solve the technical problems in the related art to a certain extent.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0006] The invention discloses an energy management device for a self-powered hydrogen fuel cell test bench, comprising a hydrogen fuel cell system to be tested and auxiliary equipment of the system to be tested. The hydrogen fuel cell system to be tested is connected to an energy feedback electronic load through relays K1 and K2 connected in series in sequence, and the auxiliary equipment of the system to be tested is connected to an energy storage battery through relays K5 and K4 connected in series in sequence, wherein a current sensor A1 and a voltage sensor V are provided at the output end of the hydrogen fuel cell system to be tested, and the current sensor A1 and the voltage sensor V are used to measure the output current and the output voltage of the hydrogen fuel cell system to be tested, respectively, and a current sensor A3 is provided at the input end of the auxiliary equipment of the system to be tested; the energy feedback electronic load is also connected in parallel with a supercapacitor, and the supercapacitor, the energy feedback electronic load and the energy storage battery are all connected in parallel, and a current sensor A2 and a current limiting resistor R connected in series in sequence are provided between the hydrogen fuel cell system to be tested and the supercapacitor, wherein the relay K3 is connected in parallel with the current limiting resistor R.

[0007] On the basis of the above technical solution, the auxiliary equipment of the system under test includes an air compressor, a water pump, a hydrogen pump, a three-way valve, a heater, a radiator and a hydrogen leakage sensor.

[0008] On the basis of the above technical solution, the energy feedback electronic load is connected to the 380V / AC mains power grid, and the energy feedback electronic load is used to feed energy back to the grid.

[0009] Based on the above technical solution, the energy storage battery is a lithium-ion battery or a lead-acid battery.

[0010] On the basis of the above technical solution, the energy storage battery is adapted to the power supply requirements of the auxiliary equipment of the system under test.

[0011] On the basis of the above technical solution, the setting parameters of the resistor R are preset according to the maximum allowable discharge and charge currents of the energy storage battery and the supercapacitor.

[0012] Based on the above technical solution, an energy management method for an autonomously powered hydrogen fuel cell test bench includes the following steps:

[0013] S1. The test procedure begins and the hydrogen fuel cell system test bench is started.

[0014] S2, control relay K4 to close, and the energy storage battery charges the supercapacitor through the current limiting resistor R; at this time, a small current is achieved through reasonable current limiting resistor R parameters to slowly charge the supercapacitor.

[0015] S3. When the supercapacitor voltage reaches the set voltage value Va, the control relay K3 is closed; the voltage value Va is the voltage value of the supercapacitor in the full state.

[0016] S4, control relay K5 is closed, and the energy storage battery supplies power to the auxiliary equipment of the system under test; when the test starts, the energy storage battery supplies power to start the auxiliary equipment of the system under test, which meets the preset starting conditions of the fuel cell to achieve hydrogen, oxygen, water, heat, etc.

[0017] S5. Issue the test time plan curve F(t)=Af 1 (t)+Bf 2 (t)+Cf 3 (t)+D, where F(t) is the loading current and the unit is ampere, t is the time, and f 1 (t) is the first current demand curve, f 2 (t) is the second current demand curve, f 3 (t) is the third current demand curve, A, B, C, D are all coupling loading correction coefficients; the energy feedback load is planned according to the test time curve F(t)=Af 1 (t)+Bf 2 (t)+Cf 3 (t)+D follows the corresponding load size in real time.

[0018] S6. Determine whether the current voltage value of the voltage sensor V meets the voltage level requirement of the system test bench. If not, enter other test modes. If yes, relays K1 and K2 are closed, the energy feedback electronic load executes the test time plan curve, and collects the current sensor A1, A2, and A3 values ​​in real time, and enters the next step. At this time, the energy feedback load keeps the loading current not greater than the A1 value according to the collected current sensor A1 value, and performs real-time comparison.

[0019] S7, determine whether the SOC of the energy storage battery satisfies α<SOC<β, if yes, execute the first loading value F 1 (t) = F (t) - A3, and keep 0 ≤ F 1 (t) ≤ A1, A1 is the current value of the real-time current sensor A1, A3 is the current value of the real-time current sensor A3, go to the next step, if not, execute the second loading value F 2 (t) = F(t) - F Battery (t), and keep 0≤F 2 (t)≤A1, proceed to the next step.

[0020] S8. Determine whether the hydrogen fuel cell under test suddenly fails and shuts down. If not, execute the entire test time plan curve and proceed to the next step. If yes, the energy feedback electronic load jumps to the no-load state and proceeds to the next step.

[0021] S9. Test completed, shut down.

[0022] On the basis of the above technical solution, when n hydrogen fuel cell systems are tested synchronously, the test time plan curve F(t)=n 1 f 1 (t)+n 2 f 2 (t)+n 3 f 3 (t)+...+n n f n (t)+E, n is a positive integer, n 1 、n 2 、n 3 ,...,n n is the coupling loading correction coefficient, and E is the supplementary correction current coefficient.

[0023] On the basis of the above technical solution, when the energy storage battery is a lithium battery, SOC<α=25% is set as the deep discharge zone, and SOC>β=80% is set as the full charge zone; when the energy storage battery is a lead-acid battery, SOC<α=45% is set as the deep discharge zone, and SOC>β=85% is set as the full charge zone.

[0024] On the basis of the above technical solution, when α<SOC<β and the hydrogen fuel cell system under test works normally, α<SOC<β is set as the slow charging zone of the energy storage battery, the control relay K4 is closed, the energy storage battery enters the charging state and the charging current is 0.01C to 0.05C until the SOC of the energy storage battery reaches the range of 75%-80%.

[0025] Compared with the prior art, the advantages of the present invention are:

[0026] Compared with the prior art, the energy management device and method of the self-powered hydrogen fuel cell test bench in the present invention is that when a fault occurs and the system shuts down, the energy feedback electronic load immediately follows the value of the current sensor A1 to perform no-load operation, thereby preventing the electronic load from continuing to execute the original loading current when the hydrogen fuel cell system under test suddenly shuts down. At the moment of shutdown, the instantaneous current required by the energy feedback electronic load is provided by the energy storage battery. In addition, the supercapacitor is connected to the bus to prevent the energy management program from failing. At this time, the instantaneous large current required by the energy feedback electronic load is provided by the supercapacitor, thereby reducing the adverse effects of the energy storage battery under excessive current discharge conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of an energy management device for an autonomously powered hydrogen fuel cell test bench according to an embodiment of the present invention;

[0028] Figure 2 It is a principle block diagram of an energy management method of an autonomously powered hydrogen fuel cell test bench in an embodiment of the present invention. DETAILED DESCRIPTION

[0029] The embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0030] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0031] In the description of the present application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device including a series of elements includes not only those elements, but also other elements that are not explicitly listed, or also includes elements inherent to such a process, method, article, or device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the process, method, article, or device including the elements.

[0032] See also Figure 1The schematic diagram of the structure of an energy management device for a self-powered hydrogen fuel cell test bench in an embodiment of the present invention is shown. The hydrogen fuel cell system under test is connected to the energy feedback electronic load through the serially connected relays K1 and K2 in turn. Relay K1 controls the connection or disconnection state of the hydrogen fuel cell system under test, and relay K2 controls the connection or disconnection state of the energy feedback electronic load. The auxiliary equipment of the system under test is connected to the energy storage battery through the serially connected relays K5 and K4 in turn. Relay K5 controls the connection or disconnection state of the input end of the auxiliary equipment of the system under test. A current sensor A1 and a voltage sensor V are provided at the output end of the hydrogen fuel cell system under test. The current sensor A1 is used to measure the output current of the hydrogen fuel cell system under test, and the voltage sensor V is used to monitor the output voltage of the hydrogen fuel cell system under test. A current sensor A3 is provided at the input end of the auxiliary equipment of the system under test, and the current sensor A3 is used to monitor the input current of the auxiliary equipment of the system under test. The energy feedback electronic load is also connected in parallel with a supercapacitor. The supercapacitor, the energy feedback electronic load and the energy storage battery are all connected in parallel. The three of them realize different directions of electric energy flow through energy control strategies to meet different working conditions and control requirements. A current sensor A2 and a current limiting resistor R are connected in series in sequence between the hydrogen fuel cell system under test and the supercapacitor. The current limiting resistor R is connected in parallel with a relay K3. The current sensor A2 is used to monitor the output current of the supercapacitor, or the current sensor A2 is used to monitor in real time the current output by the hydrogen fuel cell system under test to the energy storage battery and / or the auxiliary equipment of the system under test. The relay K3 is used to control the connection or disconnection state of the current limiting resistor R.

[0033] In this embodiment, the hydrogen fuel cell system under test is a device that converts the electrochemical reaction of hydrogen and oxygen into electrical energy, and the auxiliary equipment of the system under test includes auxiliary equipment such as air compressors and water pumps that consume electricity. In this application, the energy feedback electronic load controls the on-off state of the switch tube, and finally converts the direct current into alternating current and sends it back to the power grid through rectification, filtering and inversion of the input power supply. The device can realize bidirectional energy circulation, which can consume electrical energy and feed electrical energy back to the power grid. Therefore, the energy feedback electronic load in this embodiment is essentially a DC / AC converter that converts direct current into alternating current and sends the electrical energy into the mains power grid. The energy storage battery is an energy buffer device that provides startup energy for the system test bench or the hydrogen fuel cell system under test and absorbs excess electrical energy.

[0034] See also Figure 2The figure shows a principle block diagram of an energy management method for a self-powered hydrogen fuel cell test bench in an embodiment of the present invention. Before the system starts, ensure that the current sensor A1 collects the output current A1 of the hydrogen fuel cell system under test, the current sensor A2 collects the bypass current A2, the current sensor A3 collects the current A3 consumed by the auxiliary equipment of the system under test, and the voltage sensor V collects the output voltage V of the hydrogen fuel cell system under test. This embodiment manages the energy process based on the above-mentioned collected information, so the accuracy of the sensor data is crucial and is an important quality point of the technical solution in this application. Therefore, when conditions are sufficient, the current sensor A1, the current sensor A2, and the current sensor A3 are all set in parallel in duplicate, and the collected information is collected in duplicate, which can be used for error or fault diagnosis.

[0035] The system test bench is started, the control relay K4 is closed, and the energy storage battery slowly charges the supercapacitor through the current limiting resistor R. When the supercapacitor voltage meets the set voltage value Va, the control relay K3 is disconnected, and the supercapacitor is directly connected to the bus between the hydrogen fuel cell system under test and the energy feedback electronic load. The control relay K5 is closed, and the energy storage battery supplies power to the auxiliary equipment of the system under test, providing power for the start-up of the hydrogen fuel cell system under test.

[0036] The test time plan curve automatically generated by the host computer is, F(t)=Af 1 (t)+Bf 2 (t)+Cf 3 (t)+D, where F(t) is the loading current and the unit is ampere, t is the time, and f 1 (t) is the first current demand curve, f 2 (t) is the second current demand curve, f 3 (t) is the third current demand curve, and A, B, C, and D are all coupling loading correction coefficients. The host computer sends the load increase and decrease information of the test time plan curve to the hydrogen fuel cell system under test, and performs the next step by judging whether the current voltage value of the voltage sensor V meets the voltage level requirements of the system test bench.

[0037] If the current voltage sensor V voltage value does not meet the system test bench voltage level requirements, enter other test modes. If the current voltage sensor V voltage value meets the system test bench voltage level requirements, control relays K1 and K2 are closed, and the energy feedback electronic load executes the test time plan curve to increase and decrease loads.

[0038] Among them, when the energy feedback electronic load executes the test time plan curve to increase or decrease the load, the current sensor A1, A2, and A3 values ​​are synchronously collected.

[0039] Determine the SOC of the energy storage battery and perform corresponding operations according to the SOC situation:

[0040] When α<SOC<β, the energy feedback electronic load needs to subtract the current current sensor A3 value, that is, F 1 (t) = F (t) - A3, F 1 (t) is the first loading value, and F 1 (t) is compared with the value collected by current sensor A1 in real time, and the energy feedback electronic load is adjusted to maintain 0≤F 1 (t)≤A1. When the hydrogen fuel cell system under test is operating normally, the energy feedback electronic load performs load addition and reduction operations according to the test time plan curve until the test is completed. When the hydrogen fuel cell system under test fails and shuts down, A1=0 and t>0, due to F 1 (t)≤A1 is subject to this condition, so the energy feedback electronic load also immediately follows the change of the current sensor A1 value, and switches the energy feedback electronic load to a no-load state, thereby avoiding the sudden shutdown of the hydrogen fuel cell system under test, causing the energy feedback electronic load to continue to execute the original loading current. At this time, the instantaneous current is provided by the energy storage battery. In addition, the supercapacitor is connected to the busbar to prevent the energy management program from failing. Once the energy management program fails, the instantaneous large current required by the energy feedback electronic load is provided by the supercapacitor, thereby reducing the damage to the energy storage battery caused by the instantaneous large current discharge.

[0041] When SOC>β or SOC<α, the energy storage battery enters the charging (SOC<α) or discharging (SOC>β) state, and the energy storage battery charging or discharging information is sent to the host computer, which processes it to generate the battery planning curve F Battery (t), the energy feedback electronic load execution test time plan curve needs to be superimposed with the battery plan curve F Battery (t), that is, F 2 (t) = F(t) - F Battery (t), F 2 (t) is the second loading value, and F 2 (t) is compared with the value collected by current sensor A1 in real time, and the energy feedback electronic load is adjusted to maintain 0≤F 2 (t) ≤ A1. When the hydrogen fuel cell system under test is operating normally, the electronic load performs load addition and reduction operations according to the time plan curve until the test is completed. When the hydrogen fuel cell system under test fails and shuts down, A1=0 and t>0, due to F 2(t)≤A1 is subject to this condition, so the energy feedback electronic load also immediately follows the change of the current sensor A1 value, and switches the energy feedback electronic load to a no-load state, thereby avoiding the sudden shutdown of the hydrogen fuel cell system under test, causing the energy feedback electronic load to continue to execute the original loading current. At this time, the instantaneous current is provided by the energy storage battery. In addition, the supercapacitor is connected to the busbar to prevent the energy management program from failing. Once the energy management program fails, the instantaneous large current required by the energy feedback electronic load is provided by the supercapacitor, thereby reducing the damage to the energy storage battery caused by the instantaneous large current discharge.

[0042] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0043] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0044] The present invention is not limited to the above-mentioned embodiments. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention. The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

Claims

1. A method according to an energy management device for an autonomously powered hydrogen fuel cell test bench, wherein: An energy management device for an autonomously powered hydrogen fuel cell test bench, a hydrogen fuel cell system under test and auxiliary equipment of the system under test, characterized in that: the hydrogen fuel cell system under test is connected to an energy feedback electronic load through relays K1 and K2 connected in series in sequence, and the auxiliary equipment of the system under test is connected to an energy storage battery through relays K5 and K4 connected in series in sequence, wherein a current sensor A1 and a voltage sensor V are provided at the output end of the hydrogen fuel cell system under test, and the current sensor A1 and the voltage sensor V are used to measure the output current and output voltage of the hydrogen fuel cell system under test, respectively, and a current sensor A3 is provided at the input end of the auxiliary equipment of the system under test; the energy feedback electronic load is also connected in parallel with a supercapacitor, and the supercapacitor, the energy feedback electronic load and the energy storage battery are all connected in parallel, and a current sensor A2 and a current limiting resistor R connected in series in sequence are provided between the hydrogen fuel cell system under test and the supercapacitor, wherein the relay K3 is connected in parallel with the current limiting resistor R, and the method comprises the following steps: S1, system test bench starts; S2, control relay K4 to close, and the energy storage battery charges the supercapacitor through the current limiting resistor R; S3, when the supercapacitor voltage reaches the set voltage value Va, the control relay K3 is closed; S4, control relay K5 to close, and the energy storage battery supplies power to the auxiliary equipment of the system under test; S5. Issue the test time plan curve F(t)=Af1(t)+Bf2(t)+Cf3(t)+D, where F(t) is the loading current and the unit is ampere, t is time, f1(t) is the first current demand curve, f2(t) is the second current demand curve, f3(t) is the third current demand curve, and A, B, C, and D are all coupling loading correction coefficients; S6, determine whether the current voltage value of the voltage sensor V meets the voltage level requirement of the system test bench. If not, enter other test modes. If yes, relays K1 and K2 are closed, the energy feedback electronic load executes the test time plan curve, and collects the current sensor A1, A2, and A3 values ​​in real time, and enters the next step; S7, determine whether the energy storage battery SOC satisfies α<SOC<β, if yes, execute the first loading value F1(t)=F(t)-A3, and keep 0≤F1(t)≤A1, A1 is the current value of the real-time current sensor A1, A3 is the current value of the real-time current sensor A3, and go to the next step, if no, execute the second loading value F2(t)=F(t)-F Battery (t), and keep 0≤F2(t)≤A1, and go to the next step, where F Battery (t) Specifically, it is the battery planning curve; S8, determine whether the hydrogen fuel cell under test is shut down due to a sudden failure. If not, execute all test time plan curves and proceed to the next step. If yes, the energy feedback electronic load jumps to a no-load state and proceeds to the next step; S9. Test completed, shut down.

2. The method according to claim 1, characterized in that: When n hydrogen fuel cell systems are tested synchronously, the test time plan curve F(t)=n1f1(t)+n2f2(t)+n3f3(t)+...+n n f n (t)+E, n is a positive integer, n1, n2, n3, ..., n n is the coupling loading correction coefficient, and E is the supplementary correction current coefficient.

3. The method according to claim 1, characterized in that: When the energy storage battery is a lithium battery, SOC<α=25% is set as a deep discharge zone, and SOC>β=80% is set as a full charge zone; when the energy storage battery is a lead-acid battery, SOC<α=45% is set as a deep discharge zone, and SOC>β=85% is set as a full charge zone.

4. The method according to claim 1, characterized in that: When α<SOC<β and the hydrogen fuel cell system under test is working normally, α<SOC<β is set to the slow charging zone of the energy storage battery, the control relay K4 is closed, the energy storage battery enters the charging state and the charging current is 0.01C to 0.05C until the energy storage battery SOC reaches the interval of 75%-80%.

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