High-power multi-module hydrogen-oxygen electrochemical device for locomotive and control method

Abstract

The invention relates to the technical field of fuel cell locomotives, and provides a high-power multi-module hydrogen-oxygen electrochemical device for a locomotive and a control method.The control method comprises the steps that the number of started current cell stacks and the needed output power of each cell stack are taken, and the front-end pressure in a hydrogen loop is determined based on a multi-module system calibration table; the rotating speed set value of each loop execution device is calculated based on a linear interpolation method and a preset single-stack operation condition calibration table in the system, and the in-stack flow pressure of the cathode of each cell stack, the in-stack pressure of the anode of each cell stack and the actual value and the reference value of the temperature are calculated based on the linear interpolation method. And based on the difference between the actual value and the reference value, controlling the opening degree control quantity of other execution valves in each loop until the opening degree control quantity is smaller than a preset threshold value. According to the invention, the working parameters of each fuel cell stack can be independently controlled, differential adjustment of the output characteristics of each fuel cell stack can be realized on the premise of ensuring the requirement of the output power of the whole system, and the stability and reliability are high.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cell locomotives, and in particular to a high-power multi-module hydrogen-oxygen electrochemical device for locomotives and a control method thereof. Background Art

[0002] Proton exchange membrane fuel cell is a chemical device that can directly convert chemical energy into electrical energy. It has the advantages of high efficiency and no pollution, and has become an important tool for the application of hydrogen energy in transportation scenarios.

[0003] In the related technologies, due to the adverse effects of the increase in the number of fuel cell cells and membrane area on the system economy and durability, a single-stack hydrogen-oxygen electrochemical device is difficult to meet the application requirements of high-power scenarios such as rail transit. Therefore, the use of multi-module hydrogen-oxygen electrochemical devices has become the mainstream solution for the application of fuel cells in high-power scenarios. Multi-module hydrogen-oxygen electrochemical devices in high-power locomotive application scenarios mostly adopt an architectural design with multiple auxiliary systems, which has the disadvantages of large layout space, complex system architecture and high cost, and leads to complex control, poor control stability and reliability, and difficulty in achieving differentiated regulation. Summary of the invention

[0004] The present invention provides a high-power multi-module hydrogen-oxygen electrochemical device for locomotives and a control method thereof, which are used to solve the defects of the prior art, such as large overall occupied space, complex control system, and poor control stability and reliability.

[0005] A first aspect of the present invention provides a control method for a high-power multi-module hydrogen-oxygen electrochemical device for a locomotive, comprising: Get the current number of battery stacks turned on and the required output power P of each battery stack r1 , P r2 …P rn ; Determine the front end pressure in the hydrogen loop based on the current number of battery stacks turned on and a multi-module system calibration table preset in the system; The speed setting value RCMP of the air compressor in the air circuit is calculated based on the linear interpolation method and the single stack operating condition calibration table preset in the system. r1 , RCMP r2 …RCMP rn ; The speed setting value of the hydrogen circulation pump in the hydrogen circuit RHRB r1 , RHRB r2 …RHRB rn ; Water pump speed setting value RPMP in the heat pipe loop r1 , RPMP r2 …RPMP rn ; Calculation of reference value P of cathode pressure in battery stack based on linear interpolation method cr , cathode inlet flow reference value Q cr , anode stack pressure reference value P ar and the battery stack operating temperature reference value T r ; At the same time, obtain the actual cathode stack pressure P of the current battery stack c , the actual cathode flow rate into the stack Q c , the actual anode stack pressure P a and battery stack operating temperature T; Based on the actual cathode stack pressure P c and cathode stack pressure reference value P cr The difference between the actual cathode flow rate Q c and cathode inflow reference value Q cr The difference between the actual anode pressure Pa and the anode pressure reference value P is fed back and adjusted to obtain the control amount of the intake throttle and the back pressure valve in the air circuit; ar The difference between the operating temperature T of the battery stack and the reference value T of the battery stack operating temperature is obtained by feedback regulation. r The difference is used to obtain the control amount of the three-way valve and the proportional valve in the thermal management circuit through feedback adjustment until all the differences are less than the preset threshold.

[0006] According to a control method for a high-power multi-module hydrogen-oxygen electrochemical device for a locomotive provided by the present invention, the method for constructing a multi-module system calibration table comprises the following steps: Obtain multiple characteristic power points of a single battery stack in constant current load mode; According to each characteristic power point, the corresponding system operating conditions including air compressor speed, back pressure valve opening, cathode inlet pressure, cathode inlet flow, anode inlet pressure, hydrogen circulation pump speed, water pump speed and operating temperature are calibrated to form a single stack operating condition calibration table.

[0007] The hydrogen front end pressure in the multi-module hydrogen-oxygen electrochemical device is calibrated according to different numbers of opened battery stacks to form a multi-module system calibration table.

[0008] According to a control method for a high-power multi-module hydrogen-oxygen electrochemical device for a locomotive provided by the present invention, the speed setting value RCMP of the air compressor in the air circuit is calculated based on the linear interpolation method and the single stack operating condition calibration table preset in the system. r1 , RCMP r2 …RCMP rn ; The speed setting value of the hydrogen circulation pump in the hydrogen circuit RHRB r1 , RHRB r2 …RHRB rn; Water pump speed setting value RPMP in the heat pipe loop r1 , RPMP r2 …RPMP rn , the linear interpolation calculation method is as follows: ; ; ; ; Where P min The value in the calibration table is less than P rn The maximum power value, P max is the minimum power value greater than Prn in the calibration table, k is the interpolation factor, RCMP rn is the air compressor speed when there are n battery stacks; RCMP min The output power in the calibration table is P min Air compressor speed at RCMP rnax The output power in the calibration table is P max Air compressor speed; RHRB rn is the speed of the hydrogen circulation pump when there are n battery stacks, The output power in the calibration table is P min The speed of the hydrogen circulation pump is The output power in the calibration table is P max Hydrogen circulation pump speed at RPMP rn is the speed of the hydrogen circulation pump when there are n battery stacks, The output power in the calibration table is P min The pump speed at The output power in the calibration table is P max The pump speed at 1000 rpm; At the same time, the actual system air compressor speed setting value RCMP is calculated according to the following calculation formula r , Hydrogen circulation pump speed setting value RHRB r , Pump speed setting value RPMP r ; ; ; ; In the formula, RCMP rn is the air compressor speed when there are n battery stacks, RHRB rn is the speed of the hydrogen circulation pump when there are n battery stacks, RPMP rn is the speed of the hydrogen circulation pump when there are n battery stacks.

[0009] According to a control method for a high-power multi-module hydrogen-oxygen electrochemical device for a locomotive provided by the present invention, a reference value P of the cathode pressure of the battery stack is calculated based on a linear interpolation method. cr , cathode inlet flow reference value Q cr , anode stack pressure reference value P ar and the battery stack operating temperature reference value T r ; including the following steps: ; ; ; ; In the formula, The output power in the calibration table is P for single stack operating conditions. min The cathode pressure at the time of The output power in the calibration table is P max The cathode pressure at the time of The output power in the calibration table is P min The cathode flow rate into the stack at The output power in the calibration table is P max The cathode flow rate into the stack at The output power in the calibration table is P min Anode loading pressure at The output power in the calibration table is P max Anode loading pressure at The output power in the calibration table is P min The stack operating temperature at The output power in the calibration table is P max The stack operating temperature at .

[0010] According to a control method for a high-power multi-module hydrogen-oxygen electrochemical device for a locomotive provided by the present invention, the control method until all differences are less than a preset threshold value specifically includes: When all differences are less than 5% of the reference value, stop feedback adjustment and maintain the control amount, otherwise continue to adjust and update the control amount until all differences are less than 5% of the reference value.

[0011] A second aspect of the present invention provides a high-power multi-module hydrogen-oxygen electrochemical device for locomotives, comprising: a stack module, a hydrogen circuit, an air circuit, a thermal management circuit and a control module; the stack module comprises a plurality of fuel cell stacks, and the plurality of fuel cell stacks are connected in parallel in sequence; the hydrogen circuit is connected to each of the fuel cell stacks, and the hydrogen circuit is provided with a hydrogen storage device and a hydrogen circulation pump, and the hydrogen circuit is used to provide an anode inlet pressure for each of the fuel cell stacks; the air circuit is connected to each of the fuel cell stacks, and the air circuit is provided with an air compressor, and the air circuit is used to provide oxygen for each of the fuel cell stacks and adjust the cathode inlet pressure and flow of each fuel cell stack; the thermal management circuit is connected to each of the fuel cell stacks, and the thermal management circuit is provided with a water pump, and the heat pipe circuit is used to adjust the operating temperature of each of the fuel cell stacks; the control module is used to execute the control method of the high-power multi-module hydrogen-oxygen electrochemical device for locomotives described in any one of the above items, so as to control each circuit to reach a predetermined target value.

[0012] According to a high-power multi-module hydrogen-oxygen electrochemical device for locomotives provided by the present invention, the hydrogen circuit includes a main road, a branch road and a hydrogen circulation branch road, the main road is connected to the branch road, a plurality of fuel cell stacks are connected in parallel to the branch road, one end of the hydrogen circulation branch road is connected to each of the fuel cell stacks, the other end of the hydrogen circulation branch road is connected to the main road, and the hydrogen circulation pump is arranged on the hydrogen circulation branch road; wherein a pressure reducing valve is arranged on the main road, and a proportional valve and a pressure sensor are arranged on the passage on the branch road connected to each of the fuel cell stacks.

[0013] A high-power multi-module hydrogen-oxygen electrochemical device for locomotives provided according to the present invention also includes a bypass circuit, which is used to discharge excess gas and generated water; the hydrogen circulation branch, the air circuit and each of the fuel cell stacks are connected to the inlet end of the bypass circuit; wherein a back pressure valve is provided on the passage connecting the bypass circuit and each fuel cell stack.

[0014] According to a high-power multi-module hydrogen-oxygen electrochemical device for locomotives provided by the present invention, the air circuit is arranged in parallel with each of the fuel cell stacks; wherein an intercooler and a buffer tank are provided on the main channel of the air circuit, and an intake throttle, a flow meter and a pressure sensor are provided in sequence on each parallel channel of the air circuit.

[0015] According to a high-power multi-module hydrogen-oxygen electrochemical device for locomotives provided by the present invention, the thermal management circuit includes an input passage and a circulation passage, the input passage is connected to the coolant inlet of each fuel cell stack, the circulation passage is connected to the coolant outlet of each fuel cell stack, the inlet end of the water pump is connected to the circulation passage, and the outlet end of the water pump is connected to the input passage; wherein, a three-way valve and a radiator are sequentially arranged on the circulation passage, the three-way valve is provided with a bypass branch, the output port of the bypass branch is connected to the passage at the rear end of the radiator, and the inlet end of the water pump is also connected to a coolant storage tank; a proportional valve is provided on the passage connecting the input passage to each fuel cell stack, and a temperature sensor is provided on the passage connecting the circulation passage to the fuel cell stack.

[0016] The present invention provides a control method for a high-power multi-module hydrogen-oxygen electrochemical device for locomotives. The collected load power request is combined with the characteristic power point calibration value to independently control the hydrogen inlet pressure, air inlet pressure and flow, and operating temperature of each fuel cell stack. Under the premise of ensuring the output power demand of the overall system, the output characteristics of each fuel cell stack can be differentiated. The overall control method is simpler than that of a complex system, making the control more stable and reliable.

[0017] The present invention provides a high-power multi-module hydrogen-oxygen electrochemical device for locomotives. By constructing an air circuit, a hydrogen circuit and a thermal management circuit, only a single air compressor, a hydrogen circulation pump and a water pump are used. When arranging the system, there is no need to consider the system layout space problem caused by too many auxiliary systems, which simplifies the system structure and can reduce the manufacturing cost and layout difficulty of the multi-module hydrogen-oxygen electrochemical device. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a flow chart of the control method provided by the present invention.

[0020] Figure 2 It is a schematic diagram of the system architecture provided by the present invention.

[0021] Reference numerals: 1. Hydrogen circuit; 2. Air circuit; 3. Heat pipe circuit; 31. Bypass branch; 4. Bypass circuit; 5. Fuel cell module. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limitations on the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0024] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" 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 an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0025] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0026] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0027] Combine the following Figure 1 A control method for a high-power multi-module hydrogen-oxygen electrochemical device for a locomotive of the present invention is described, which specifically includes the following steps: Step S1: Obtain the number of currently enabled battery stacks and the required output power of each battery stack (assuming the total number of battery stacks is n) P r1 , P r2 …P rn .

[0028] Specifically, the total power required by the device is obtained and distributed to each battery stack, so that the total power demand is met in this way, and the power distribution of each battery stack can be achieved through the following steps.

[0029] Step S2: determining the front end pressure in the hydrogen loop 1 based on the current number of battery stacks turned on and a multi-module system calibration table preset in the system.

[0030] Specifically, the number of cell stacks opened affects the front-end pressure of the hydrogen loop 1 in the system, and the pressure at the front end of the hydrogen loop 1 and the size of the pressure reducing valve can affect the flow of hydrogen in the passage and the anode stack entry pressure. That is, when the number of cell stacks opened in the system is increased, the front-end pressure of the hydrogen loop 1 needs to be increased accordingly to provide sufficient anode stack entry pressure and flow.

[0031] When setting up the tool, the hydrogen front-end pressure value that matches the number of battery stacks opened is obtained through preliminary test records, and the recorded data is formed into a multi-module system calibration table to realize the control and calibration of the total anode stack pressure. The multi-module system calibration table is entered into the system, and the control signal is transmitted by obtaining the number of battery stacks during automatic control, so that the actuator executes the corresponding adjustment of the hydrogen front-end pressure.

[0032] Step S3: Calculate the speed setting value RCMP of the air compressor in the air circuit 2 based on the linear interpolation method and the single stack operating condition calibration table preset in the system. r1 , RCMPr2 …RCMP rn ; The speed setting value of the hydrogen circulation pump in hydrogen loop 1 RHRB r1 , RHRB r2 …RHRB rn ; Water pump speed setting value RPMP in heat pipe loop 3 r1 , RPMP r2 …RPMP rn .

[0033] Specifically, the calculation method of a single battery stack is calculated using a specific calculation method of linear interpolation, which specifically includes: ; ; ; ; Where P min The value in the calibration table is less than P rn The maximum power value, P max is the minimum power value greater than Prn in the calibration table, k is the interpolation factor, RCMP rn is the air compressor speed when there are n battery stacks; RCMP min The output power in the calibration table is P min Air compressor speed at RCMP rnax The output power in the calibration table is P max Air compressor speed; RHRB rn is the speed of the hydrogen circulation pump when there are n battery stacks, The output power in the calibration table is P min The speed of the hydrogen circulation pump is The output power in the calibration table is P max Hydrogen circulation pump speed at RPMP rn is the speed of the hydrogen circulation pump when there are n battery stacks, The output power in the calibration table is P min The pump speed at The output power in the calibration table is P max The pump speed at 1000 rpm; At the same time, when calculating multiple battery stacks, the air compressor speed setting value RCMP in the actual system is calculated according to the following calculation formula: r , Hydrogen circulation pump speed setting value RHRB r , Pump speed setting value RPMP r ; ; ; ; In the formula, RCMP rn is the air compressor speed when there are n battery stacks, RHRB rn is the speed of the hydrogen circulation pump when there are n battery stacks, RPMP rn is the speed of the hydrogen circulation pump when there are n battery stacks.

[0034] It can be understood that when the required output power needs to be achieved, the speed of the actuators in each circuit (air compressor speed, hydrogen circulation pump speed and water pump speed) is specifically calculated, where the specific calculation method of the linear interpolation method is used to calculate the speed of each actuator for a single battery stack, and when multiple battery stacks are arranged, it is calculated by linear combination.

[0035] Among them, the method for constructing the multi-module system calibration table is to perform a load test on a single battery stack, that is, to connect a single battery stack to a load for testing, and specifically includes the following steps: Under the constant current load mode, multiple characteristic power points of a single battery stack are obtained; according to each characteristic power point, the corresponding system operating conditions including air compressor speed, back pressure valve opening, cathode inlet pressure, cathode inlet flow, anode inlet pressure, hydrogen circulation pump speed, water pump speed, and operating temperature are calibrated, and the actual operating condition data corresponding to each characteristic power point are recorded to form a single stack operating condition calibration table. Afterwards, a similar actual test method is used to determine the appropriate hydrogen front-end pressure of the multi-module hydrogen-oxygen electrochemical device according to the number of battery stacks turned on, and a multi-module system calibration table is formed, in which the number of battery stacks and the hydrogen front-end pressure have a corresponding relationship, and the corresponding relationship is the appropriate hydrogen front-end pressure. For details, please refer to the above records and the table records in the following embodiments.

[0036] Step S4: Calculate the reference value P of the cathode pressure of the battery stack based on the linear interpolation method cr , cathode inlet flow reference value Q cr , anode stack pressure reference value P ar and the battery stack operating temperature reference value T r ; At the same time, obtain the actual cathode stack pressure P of the current battery stack c , the actual cathode flow rate into the stack Q c , the actual anode stack pressure P a and the battery stack operating temperature T.

[0037] Specifically, the calculation formulas for each reference value are as follows, and the reference value is calculated by the following calculation supply.

[0038] ; ; ; ; Where k is the interpolation factor, The output power in the calibration table is P for single stack operating conditions. min The cathode pressure at the time of The output power in the calibration table is P max The cathode pressure at the time of The output power in the calibration table is P min The cathode flow rate into the stack at The output power in the calibration table is P max The cathode flow rate into the stack at The output power in the calibration table is P min Anode loading pressure at The output power in the calibration table is P max Anode loading pressure at The output power in the calibration table is P min The stack operating temperature at The output power in the calibration table is P max The stack operating temperature at .

[0039] The actual measured values ​​of each data can be measured in real time by setting sensors in the system. For example, pressure sensors are set at the entrances of the two electrodes of the battery stack to monitor the anode stack pressure P a and cathode stack pressure P c When the temperature needs to be detected, a temperature sensor can be set at the outlet of each battery stack coolant to measure the actual temperature.

[0040] Step S5: Based on the actual cathode stack pressure P c and cathode stack pressure reference value P cr The difference between the actual cathode flow rate Q c and cathode inflow reference value Q cr The difference between the actual anode pressure Pa and the anode pressure reference value P is fed back and adjusted to obtain the control amount of the intake throttle and the back pressure valve in the air circuit 2; ar The difference between the operating temperature T of the battery stack and the reference value T of the battery stack operating temperature is obtained by feedback regulation. r The difference is used to obtain the control amount of the three-way valve and the proportional valve in the thermal management circuit through feedback adjustment until all the differences are less than the preset threshold.

[0041] It can be understood that the difference between each actual collected data and the reference value can reflect whether the actual state is close to the target state, thereby achieving effective control.

[0042] Specifically, when all differences are less than 5% of the reference value, the feedback adjustment is stopped and the control amount is maintained, otherwise the control amount is adjusted and updated until all differences are less than 5% of the reference value. That is, by setting the preset threshold so that the actual value is closer to the reference value, the expected goal can be achieved, the total power demand can be met, and the state of each battery stack is stable.

[0043] The following is an example with two battery stacks and provides a specific calibration table for explanation.

[0044] In a specific example, the multi-module hydrogen-oxygen electrochemical device architecture is a dual-module architecture for locomotives, with a total power of 240kW, and each fuel cell module has a rated power of 120kW. The partial output power of the hydrogen-oxygen electrochemical device and the operating parameters such as the air compressor speed, back pressure valve opening, cathode inlet pressure, cathode inlet flow, anode inlet pressure, hydrogen circulation pump speed, water pump speed, and operating temperature are shown in the following single stack operating condition calibration table, and the hydrogen front end pressure is shown in the system calibration table: 120KW fuel cell module partial single stack operating condition calibration table

[0045] Multi-module system calibration table

[0046] The control module receives the power request sent by the vehicle controller, obtains the startup number of the fuel cell module 5 and the power setting value P of the first fuel cell stack and the second fuel cell stack r1 With P r2 Then determine the hydrogen front pressure P through the system calibration table fr , and then obtain the air compressor speed setting value RCMP from the calibration table by linear interpolation method r1 , RCMP r2 ; Hydrogen circulation pump speed setting value RHRB r1 , RHRB r2 ; Pump speed setting value RPMP r1 , RPMP r2 .

[0047] At the same time, the actual system air compressor speed setting value RCMP is calculated according to the following calculation formula r , Hydrogen circulation pump speed setting value RHRB r , Pump speed setting value RPMP r , and sent to the air compressor, hydrogen circulation pump and water pump.

[0048] ; ; ; Then, the control module feedbacks the actual cathode stack pressure P according to the feedback of each battery stack sensor. c1 , P c2 and cathode stack pressure P cr1 , P cr2 The difference between the reference value and the actual cathode flow rate Q c1 , Q c2 and cathode inflow reference value Q cr1 , Q cr2 Feedback adjustment is performed to obtain the intake throttle and back pressure valve control quantity; according to the feedback of each battery stack sensor, the actual anode stack pressure P a1 , P a2 and the anode stack pressure reference value P ar1 , P ar2 The difference between the actual working temperature T1 and T2 of each battery stack sensor and the reference value T of the battery stack working temperature are fed back and adjusted to obtain the control amount of the proportional valve of the hydrogen circuit 1; r1 , T r2 The difference between the reference value and the control value of the three-way valve and the proportional valve in the thermal management circuit is obtained by feedback adjustment. When the difference is less than 5% of the reference value, the feedback adjustment is stopped and the control value is maintained. Otherwise, the control value is continued to be adjusted and updated.

[0049] In summary, the present invention provides a control method for a high-power multi-module hydrogen-oxygen electrochemical device for locomotives. The collected load power request is combined with the characteristic power point calibration value to independently control the hydrogen loop 1 inlet pressure, the air loop 2 inlet pressure and flow, and the operating temperature of each fuel cell stack. Under the premise of ensuring the output power demand of the overall system, differentiated adjustment of the output characteristics of each fuel cell stack can be achieved, and the overall control method is simpler than that of a complex system, making the control more stable and reliable.

[0050] Combine the following Figure 2The invention describes a high-power multi-module hydrogen-oxygen electrochemical device for locomotives, including a stack module 5, a hydrogen circuit 1, an air circuit 2, a thermal management circuit 3 and a control module; the stack module 5 includes a plurality of fuel cell stacks, and the plurality of fuel cell stacks are connected in parallel in sequence; the hydrogen circuit 1 is connected to each fuel cell stack, and the hydrogen circuit 1 is provided with a hydrogen storage device and a hydrogen circulation pump, and the hydrogen circuit 1 is used to provide anode inlet pressure for each fuel cell stack; the air circuit 2 is connected to each fuel cell stack, and the air circuit 2 is provided with an air compressor, and the air circuit 2 is used to provide oxygen for each fuel cell stack and adjust the cathode inlet pressure and flow of each fuel cell stack; the thermal management circuit is connected to each fuel cell stack, and the thermal management circuit is provided with a water pump, and the heat pipe circuit 3 is used to adjust the working temperature of each fuel cell stack; the control module is used to execute any of the above control methods of the high-power multi-module hydrogen-oxygen electrochemical device for locomotives, so as to control each circuit to reach a predetermined target value. In the high-power multi-module hydrogen-oxygen electrochemical device, an auxiliary system is required to meet the work of multiple fuel cell stacks. In this embodiment, the auxiliary system is simple, so that the overall system occupies a small space, the overall system is simple to construct, and the cost is low.

[0051] It is understandable that each fuel cell of the traditional multi-module hydrogen-oxygen electrochemical system needs to be configured with a separate auxiliary system to work. This approach makes the overall system complex, costly, and complex to control. The present embodiment, on the other hand, uses a single loop to arrange multiple fuel cells, thereby achieving efficient control of multiple modules at high power.

[0052] Specifically, the necessary reaction materials are provided to the fuel cell through the air circuit 2 and the hydrogen circuit 1, thereby realizing the conversion of chemical energy into electrical energy. A large amount of heat is generated during the operation of the fuel cell, and the coolant circulation is driven by the thermal management circuit to take away the operating temperature of the fuel cell and ensure the stability of the entire system.

[0053] In the specific configuration, each fuel cell stack is connected in parallel in sequence through a primary DC / DC converter, and then connected to a secondary DC / DC converter, so as to form the entire fuel cell stack module 5 in parallel.

[0054] According to an embodiment provided by the present invention, the hydrogen circuit 1 includes a trunk, a branch and a hydrogen circulation branch. The trunk is connected to the branch, and multiple fuel cell stacks are connected in parallel to the branch. One end of the hydrogen circulation branch is connected to each fuel cell stack, and the other end of the hydrogen circulation branch is connected to the trunk. A hydrogen circulation pump is arranged on the hydrogen circulation branch; wherein a pressure reducing valve is arranged on the trunk, and a proportional valve and a pressure sensor are arranged on the passage connected to each fuel cell stack on the branch. The hydrogen circuit 1 is used to provide hydrogen to the battery stack for fuel cell reaction. In this embodiment, the overall pressure and overall flow can be adjusted by arranging a pressure reducing valve on the trunk, and then the pressure and flow entering the respective fuel cell stack can be adjusted by the proportional valve, so as to achieve the purpose of controlling a single fuel cell stack.

[0055] In a specific example, the hydrogen loop 1 is connected to the anode end of each fuel cell. The hydrogen storage device is connected to the main road, and a pressure regulating valve is provided on the hydrogen storage device to adjust the gas pressure output by the hydrogen storage device. Then, a solenoid valve and a pressure reducing valve are provided on the main section. The pressure reducing valve can reach the set opening according to the multi-module system calibration table and the number of fuel cell stacks turned on, so that the pressure at the front end of the hydrogen loop 1 at the pressure reducing valve position reaches a predetermined value. Then, the hydrogen after pressure regulation enters different fuel cell stacks respectively through the proportional valve, and a pressure sensor is provided at the rear end of the proportional valve to detect the anode inlet pressure of the fuel cell stack.

[0056] Furthermore, it is inevitable that some hydrogen will remain in the fuel cell during the reaction process. The remaining hydrogen is circulated through the hydrogen circulation branch, and specifically the remaining hydrogen is extracted by a hydrogen circulation pump to achieve the recycling of hydrogen and reduce the overall cost of use.

[0057] According to an embodiment provided by the present invention, the device further includes a bypass loop 4, which is used to discharge excess gas and generated water; the hydrogen circulation branch, the air loop 2 and each fuel cell stack are connected to the inlet end of the bypass loop 4; wherein, a back pressure valve is provided on the passage connecting the bypass loop 4 and each fuel cell stack. During the operation of the fuel cell, some gas and generated water will be discharged. In this embodiment, the outlet of the bypass passage is connected to the outside to achieve the discharge of gas and water.

[0058] In the specific setting, the hydrogen circulation branch is connected to the anode end of the fuel cell, which is mainly used for the circulation of hydrogen and also for discharging the water generated when the fuel cell stack is working, wherein the hydrogen part is driven by the hydrogen circulation pump for circulation, and the water is discharged through the battery valve on the bypass loop 4. The inlet end of the bypass loop 4 is also connected to the air loop 2 and the cathode end of the fuel cell, wherein a bypass valve is provided on the connection passage between the bypass loop 4 and the air loop 2, which acts to neutralize the anode hydrogen used for purging through the bypass air during the start-up purging and shutdown purging of the fuel cell stack, thereby avoiding the direct tail discharge of high-concentration hydrogen.

[0059] The back pressure valve can balance pressure and control flow. Specifically, the back pressure valve is installed at the end of the pipeline to control the upstream pressure and ensure that air can be supplied to the fuel cell stack in a stable state, thereby maintaining the balance of inlet and outlet pressures. The back pressure valve changes the flow area by adjusting the opening, thereby affecting the flow capacity of the fluid. By adjusting the back pressure valve opening, the flow of the fluid can be controlled to meet the needs of the fuel cell system.

[0060] In an example provided by the present invention, the air circuit 2 is arranged in parallel with each fuel cell stack; wherein, an intercooler and a buffer tank are arranged on the main channel of the air circuit 2, and an intake throttle, a flow meter and a pressure sensor are arranged in sequence on each parallel channel of the air circuit 2. When the fuel cell is working, it needs to continuously input air to achieve efficient operation. In this embodiment, through the arrangement of the air circuit 2, the air can enter each fuel cell stack in sequence through the intake throttle, the flow meter and the pressure sensor, so as to realize the control of the flow and pressure entering the fuel cell stack.

[0061] It is understandable that after the air compressor compresses the air, the air temperature rises, which is not conducive to the storage and transportation of the gas. In this embodiment, the storage of compressed air is achieved through the provision of an intercooler and a buffer tank, making the stability and reliability of the entire system higher. In addition, the pressure and flow of the air entering different fuel cell stacks can be adjusted through the provision of an intake throttle, thereby achieving control of a single fuel cell stack.

[0062] Furthermore, the air circuit 2 is connected to the cathode end of each fuel cell stack. By setting a pressure sensor on the passage connected to the cathode end of the fuel cell, the pressure of the cathode entering the stack of the fuel cell can be detected, and a flow meter is also provided on the passage to measure the cathode entering the stack flow on each passage.

[0063] In the real-time mode provided by the present invention, the thermal management circuit includes an input passage and a circulation passage, the input passage is connected to the coolant inlet of each fuel cell stack, the circulation passage is connected to the coolant outlet of each fuel cell stack, the inlet end of the water pump is connected to the circulation passage, and the outlet end of the water pump is connected to the input passage; wherein, a three-way valve and a radiator are sequentially arranged on the circulation passage, the three-way valve is provided with a bypass branch 31, the output port of the bypass branch 31 is connected to the passage at the rear end of the radiator, and the inlet end of the water pump is also connected to a coolant storage tank; a proportional valve is arranged on the passage connecting the input passage to each fuel cell stack, and a temperature sensor is arranged on the passage connecting the circulation passage to the fuel cell stack. The thermal management circuit is used to adjust the heat emitted by the fuel cell stack during operation. In this embodiment, the cooling of the circulating coolant can be achieved through the radiator, thereby facilitating the overall flow of the circulating liquid.

[0064] It is understandable that by providing a proportional valve on the input passage, the flow of coolant input into different fuel cell stacks can be controlled, thereby achieving independent control of different fuel cell stacks. And by providing a temperature sensor on the circulation passage to detect the temperature of the coolant, the rising temperature of the coolant can be obtained, thereby controlling whether it is necessary to increase the flow of water entering the fuel cell stack.

[0065] Furthermore, the three-way valve is set so that part of the water in the circulation path is circulated after being dispersed through the radiator, and the other part of the water is directly circulated after entering the water pump through the bypass branch 31. Specifically, the bypass branch 31 can provide a good supply of coolant for the entire thermal management circuit. When regulation is required, the flow rate of different flow paths of the three-way valve can be controlled to meet the coolant demand in different scenarios.

[0066] For example, when the temperature measured by the temperature sensor is higher than the threshold, it is necessary to increase the coolant flow in the corresponding fuel cell. By adjusting the opening of the bypass branch 31 and the opening of the proportional valve, the flow entering the fuel cell is increased, thereby achieving the purpose of rapid cooling.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A control method for a high-power multi-module hydrogen-oxygen electrochemical device for a locomotive, characterized in that: include: Get the current number of battery stacks turned on and the required output power P of each battery stack r1 , P r2 …P rn ; Determine the front end pressure in the hydrogen loop based on the current number of battery stacks turned on and a multi-module system calibration table preset in the system; The speed setting value RCMP of the air compressor in the air circuit is calculated based on the linear interpolation method and the single stack operating condition calibration table preset in the system. r1 , RCMP r2 …RCMP rn ; The speed setting value of the hydrogen circulation pump in the hydrogen circuit RHRB r1 , RHRB r2 …RHRB rn ; Water pump speed setting value RPMP in the heat pipe loop r1 , RPMP r2 …RPMP rn ; Calculation of reference value P of cathode pressure in battery stack based on linear interpolation method cr , cathode inlet flow reference value Q cr , anode stack pressure reference value P ar and the battery stack operating temperature reference value T r ; At the same time, obtain the actual cathode stack pressure P of the current battery stack c , the actual cathode flow rate into the stack Q c , the actual anode stack pressure P a and battery stack operating temperature T; Based on the actual cathode stack pressure P c and cathode stack pressure reference value P cr The difference between the actual cathode flow rate Q c and cathode inflow reference value Q cr The difference between the actual anode pressure Pa and the anode pressure reference value P is fed back and adjusted to obtain the control amount of the intake throttle and the back pressure valve in the air circuit; ar The difference between the operating temperature T of the battery stack and the reference value T of the battery stack operating temperature is obtained by feedback regulation. r The difference is used to obtain the control amount of the three-way valve and the proportional valve in the thermal management circuit through feedback adjustment until all the differences are less than the preset threshold.

2. The control method of the high-power multi-module hydrogen-oxygen electrochemical device for locomotives according to claim 1 is characterized in that: The method for constructing the single stack operating condition calibration table and the multi-module system calibration table comprises the following steps: Obtain multiple characteristic power points of a single battery stack in constant current load mode; According to each characteristic power point, the corresponding system operating conditions including air compressor speed, back pressure valve opening, cathode inlet pressure, cathode inlet flow, anode inlet pressure, hydrogen circulation pump speed, water pump speed, and operating temperature are calibrated to form a single stack operating condition calibration table; The hydrogen front end pressure in the multi-module hydrogen-oxygen electrochemical device is calibrated according to different numbers of opened battery stacks to form a multi-module system calibration table.

3. The control method of the high-power multi-module hydrogen-oxygen electrochemical device for locomotives according to claim 1 is characterized in that: The speed setting value RCMP of the air compressor in the air circuit is calculated based on the linear interpolation method and the single stack operating condition calibration table preset in the system. r1 , RCMP r2 …RCMP rn ; The speed setting value of the hydrogen circulation pump in the hydrogen circuit RHRB r1 , RHRB r2 …RHRB rn ; Water pump speed setting value RPMP in the heat pipe loop r1 , RPMP r2 …RPMP rn , the linear interpolation calculation method is as follows: ； ； ； ； Where P min The value in the calibration table is less than P rn The maximum power value, P max is the minimum power value greater than Prn in the calibration table, k is the interpolation factor, RCMP rn is the air compressor speed when there are n battery stacks; RCMP min The output power in the calibration table is P min Air compressor speed at RCMP rnax The output power in the calibration table is P max Air compressor speed; RHRB rn is the speed of the hydrogen circulation pump when there are n battery stacks, The output power in the calibration table is P min The speed of the hydrogen circulation pump is The output power in the calibration table is P max Hydrogen circulation pump speed at RPMP rn is the speed of the hydrogen circulation pump when there are n battery stacks, The output power in the calibration table is P min The pump speed at The output power in the calibration table is P max The pump speed at 1000 rpm; At the same time, calculate the air compressor speed setting value RCMP in the actual system according to the following calculation formula r , Hydrogen circulation pump speed setting value RHRB r , Pump speed setting value RPMP r ; ； ； ； In the formula, RCMP rn is the air compressor speed when there are n battery stacks, RHRB rn is the speed of the hydrogen circulation pump when there are n battery stacks, RPMP rn is the speed of the hydrogen circulation pump when there are n battery stacks.

4. The control method of the high-power multi-module hydrogen-oxygen electrochemical device for locomotives according to claim 1 is characterized in that: Calculation of reference value P of cathode pressure in battery stack based on linear interpolation method cr , cathode inlet flow reference value Q cr , anode stack pressure reference value P ar and the battery stack operating temperature reference value T r ; The following steps are involved: ； ； ； ； In the formula, The output power in the calibration table is P for single stack operating conditions. min The cathode pressure at the time of The output power in the calibration table is P max The cathode pressure at the time of The output power in the calibration table is P min The cathode flow rate into the stack at The output power in the calibration table is P max The cathode flow rate into the stack at The output power in the calibration table is P min Anode loading pressure at The output power in the calibration table is P max Anode loading pressure at The output power in the calibration table is P min The stack operating temperature at The output power in the calibration table is P max The stack operating temperature at .

5. The control method of the high-power multi-module hydrogen-oxygen electrochemical device for locomotives according to claim 1 is characterized in that: The step of waiting until all the differences are less than a preset threshold specifically includes: When all differences are less than 5% of the reference value, stop feedback adjustment and maintain the control amount, otherwise continue to adjust and update the control amount until all differences are less than 5% of the reference value.

6. A high-power multi-module hydrogen-oxygen electrochemical device for locomotives, characterized in that: include: A fuel cell stack module, wherein the fuel cell stack module comprises a plurality of fuel cell stacks, and the plurality of fuel cell stacks are sequentially connected in parallel; A hydrogen circuit, the hydrogen circuit is in communication with each of the fuel cell stacks, the hydrogen circuit is provided with a hydrogen storage device and a hydrogen circulation pump, and the hydrogen circuit is used to provide an anode inlet pressure for each of the fuel cell stacks; An air circuit, the air circuit is connected to each of the fuel cell stacks, the air circuit is provided with an air compressor, and the air circuit is used to provide oxygen to each of the fuel cell stacks and adjust the pressure and flow of the cathode inlet of each fuel cell stack; A heat management circuit, the heat management circuit is in communication with each of the fuel cell stacks, the heat management circuit is provided with a water pump, and the heat pipe circuit is used to adjust the operating temperature of each of the fuel cell stacks; A control module, wherein the control module is used to execute the control method of the locomotive high-power multi-module hydrogen-oxygen electrochemical device according to any one of claims 1 to 5, so as to control each circuit to reach a predetermined target value.

7. The high-power multi-module hydrogen-oxygen electrochemical device for locomotives according to claim 6, characterized in that: The hydrogen circuit includes a main road, a branch road and a hydrogen circulation branch road, the main road is connected to the branch road, a plurality of fuel cell stacks are connected in parallel to the branch road, one end of the hydrogen circulation branch road is connected to each fuel cell stack, and the other end of the hydrogen circulation branch road is connected to the main road, and the hydrogen circulation pump is arranged on the hydrogen circulation branch road; Wherein, a pressure reducing valve is arranged on the main road, and a proportional valve and a pressure sensor are arranged on the passage connected to each fuel cell stack on the branch road.

8. The high-power multi-module hydrogen-oxygen electrochemical device for locomotives according to claim 7, characterized in that: It also includes a bypass loop, which is used to discharge excess gas and generated water; the hydrogen circulation branch, the air circuit and each of the fuel cell stacks are connected to the inlet end of the bypass loop; Wherein, a back pressure valve is provided on the passage connecting the bypass loop and each fuel cell stack.

9. The high-power multi-module hydrogen-oxygen electrochemical device for locomotives according to claim 6, characterized in that: The air circuit is arranged in parallel with each of the fuel cell stacks; Wherein, an intercooler and a buffer tank are arranged on the main channel of the air circuit, and an intake throttle, a flow meter and a pressure sensor are arranged in sequence on each parallel channel of the air circuit.

10. The high-power multi-module hydrogen-oxygen electrochemical device for locomotives according to claim 6, characterized in that: The thermal management circuit includes an input passage and a circulation passage, wherein the input passage is connected to a coolant inlet of each fuel cell stack, the circulation passage is connected to a coolant outlet of each fuel cell stack, the inlet end of the water pump is connected to the circulation passage, and the outlet end of the water pump is connected to the input passage; Among them, a three-way valve and a radiator are sequentially provided on the circulation passage, a bypass branch is provided on the three-way valve, the output port of the bypass branch is connected to the passage at the rear end of the radiator, and the inlet end of the water pump is also connected to a coolant storage tank; a proportional valve is provided on the passage connecting the input passage and each of the fuel cell stacks, and a temperature sensor is provided on the passage connecting the circulation passage and the fuel cell stack.

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