Hydrogen, electricity and heat multi-energy coupling method and system based on multi-machine fuel cell

Abstract

The invention provides a hydrogen-electricity-heat multi-energy coupling method and system based on a multi-machine fuel cell, and belongs to the technical field of hydrogen-electricity-heat multi-energy coupling, and the method comprises the steps: collecting the sum of the actual output power of all galvanic piles at the current moment, and a user-side electrical load; outputting the sum of the reference output power of all the electric piles through a total fuzzy logic PID controller by taking the user-side electric load as an input reference value and the sum of the actual output power of all the electric piles as an input control value; the sum of the reference output power of all the electric piles is input into an efficiency optimal power distribution model, and the number of the electric piles needing to be started and the reference output power are output; the reference output power and the actual output power value of each galvanic pile serve as an input reference value and a control value respectively, galvanic pile gas flow is output through a sub-fuzzy logic PID controller of an electromagnetic valve corresponding to the galvanic pile, and the gas flow of a pipeline where the galvanic pile is located is controlled. According to the invention, power distribution and waste heat recovery management of the multi-machine fuel cell system are realized.

Description

Technical Field

[0001] The present application belongs to the technical field of hydrogen-electric-thermal multi-energy coupling, and more specifically, to a hydrogen-electric-thermal multi-energy coupling method and system based on a multi-machine fuel cell. Background Art

[0002] As a clean secondary energy source, hydrogen has a high calorific value and the only reaction product is water. It is an ideal medium between wind power or photovoltaic power generation and residential loads. Hydrogen fuel cells are electrochemical devices that directly convert the chemical energy of hydrogen into electrical energy. However, during the hydrogen-electricity conversion process in the fuel cell, almost half of the hydrogen chemical energy is lost in the form of heat. Therefore, recovering the waste heat generated by fuel cells and operating them in the form of cogeneration is an ideal user-side energy supply solution.

[0003] The stack is the main heat-generating component of the fuel cell system, usually accounting for more than 90% of the total waste heat of the system, so most of the related technologies focus on waste heat recovery of the stack. However, some auxiliary equipment of the fuel cell and the stack exhaust will generate some waste heat. However, it is not economically worthwhile to establish an independent heat recovery system for these small heat sources, resulting in the ineffective use of this part of waste heat.

[0004] In addition, a single large fuel cell has deficiencies in reliability and durability, so multi-fuel cell systems are often used in engineering for collaborative operation. By using a reasonable multi-energy coupling architecture and energy management method, the output power and electrical efficiency of the fuel cell system can be improved and fuel consumption can be reduced. However, in most studies on the performance improvement of hydrogen-electric-thermal multi-energy coupling systems, the fuel cell has only one stack, and there is little research on the power distribution and waste heat recovery management of multi-fuel cell systems. Summary of the invention

[0005] In view of the defects of the prior art, the purpose of this application is to provide a hydrogen-electric-thermal multi-energy coupling method and system based on multi-fuel cells, aiming to solve the power distribution and waste heat recovery management of multi-fuel cell systems.

[0006] In a first aspect, an embodiment of the present application provides a hydrogen-electric-thermal multi-energy coupling method based on a multi-machine fuel cell, comprising:

[0007] Collect the actual output power sum of all fuel cell stacks in the system at the current moment, as well as the user-side electrical load;

[0008] The user-side electric load is used as the input reference value, the sum of the actual output powers of all fuel cell stacks is used as the input control value, and the sum of the reference output powers of all fuel cell stacks is output through the total fuzzy logic PID controller;

[0009] The sum of the reference output powers of all fuel cell stacks is input into the efficiency optimal power allocation model, and the number of fuel cell stacks to be started and the corresponding reference output powers are output;

[0010] The reference output power and actual output power value of each fuel cell stack are used as the input reference value and input control value respectively, and the fuzzy logic PID controller of the solenoid valve corresponding to the fuel cell stack outputs the stack gas flow to control the gas flow of the pipeline.

[0011] Optionally, outputting the number of fuel cell stacks that need to be started and the corresponding reference output power includes:

[0012] The system efficiency is optimal when the output power of different fuel cell stacks is the same;

[0013] Determine the power corresponding to the intersection of the power efficiency curves under the condition of average power distribution of n+1 fuel cell stacks and average power distribution of n fuel cell stacks as W tn ;

[0014] If W tn If the power W is less than the sum of the reference output powers of all fuel cell stacks, then the power W corresponding to the intersection of the power efficiency curves under the conditions of the average power distribution of n+2 fuel cell stacks and the average power distribution of n+1 fuel cell stacks is determined. t(n+1) and compared with the sum of the reference output powers of all fuel cell stacks;

[0015] If W tn If the reference output power is greater than or equal to the sum of the reference output powers of all fuel cell stacks, the number of fuel cell stacks that need to be started is n, and the reference output power of the n fuel cell stacks is calculated based on the principle of average power distribution.

[0016] Optionally, the method further comprises:

[0017] Compare the waste heat recovery heat and the heat load on the user side at the current moment, and control whether the hydrogen burner is working and whether the hot water storage tank releases stored heat to the outside based on the waste heat priority principle.

[0018] Optionally, the waste heat priority principle is used to control whether the hydrogen burner is working at the current moment and whether the hot water storage tank releases stored heat externally, including:

[0019] If the waste heat recovery heat is greater than or equal to the user-side heat load, the waste heat recovery heat will be used for heating alone, and any excess heat will be stored in a hot water storage tank;

[0020] If the waste heat recovery heat is less than the user-side heat load, it is determined whether there is heat storage in the hot water storage tank. If so, supplementary heating is provided through the hot water storage tank.

[0021] If the hot water tank does not store heat or does not store enough heat, the hydrogen burner will be used to provide additional heat.

[0022] Optionally, waste heat recovery includes a hot water storage tank providing water with a temperature lower than the stack outlet temperature to each fuel cell stack through a second water pump to carry away the stack waste heat, an intercooler cooling the high-temperature air to discharge the heat of the hot water, and the heat of the hot water generated by the electrochemical reaction of the fuel cell stack.

[0023] Optionally, the actual output power of the system is obtained by subtracting the auxiliary power from the sum of the actual output power of all fuel cell stacks.

[0024] In a second aspect, the present application also provides a hydrogen-electric-thermal multi-energy coupling system based on a multi-machine fuel cell, comprising:

[0025] Multiple fuel cell stacks, air compressors, hydrogen compressors, intercoolers, hydrogen storage tanks, hydrogen mixing tanks and hot water storage tanks connected in parallel;

[0026] During the operation of the system, the air compressor compresses the incoming air, which is then cooled to the stack inlet temperature through the intercooler and then enters each fuel cell stack through the air solenoid valve; normal temperature water enters the intercooler through the first water pump to cool the high temperature air, and the heated water enters the hot water storage tank;

[0027] The hydrogen storage tank is configured to store new hydrogen, which is mixed with unreacted hydrogen exhausted from the fuel cell stack in the hydrogen mixing tank and then enters each fuel cell stack through the hydrogen solenoid valve;

[0028] The hot water generated by the electrochemical reaction of each fuel cell stack enters the hot water storage tank, and the hot water storage tank provides water with a temperature lower than the stack outlet temperature to each fuel cell stack through the second water pump to remove the waste heat of the stack. The heated water enters the hot water storage tank again.

[0029] Optionally, the system further comprises a hydrogen burner, and the hydrogen burner and the hydrogen storage tank are connected via a hydrogen solenoid valve;

[0030] When the hot water in the hot water storage tank is not enough to supply the heat load on the user side, normal temperature water enters the hydrogen burner through the fourth water pump, and the hydrogen in the hydrogen storage tank enters the hydrogen burner through the connected hydrogen solenoid valve for combustion and heating, and the heated high-temperature water enters the hot water storage tank to supplement the heating.

[0031] Optionally, normal temperature water enters the hot water tank through the third water pump to lower the temperature of the hot water tank, so that the water provided by the hot water tank to each fuel cell stack through the second water pump is lower than the stack outlet temperature.

[0032] Optionally, the unreacted air exhausted from the fuel cell stack is used to preheat the hydrogen in the hydrogen mixing tank; the unreacted hydrogen exhausted from the fuel cell stack is compressed by a hydrogen compressor and then enters the hydrogen mixing tank.

[0033] In a third aspect, the present application also provides a hydrogen-electric-thermal multi-energy coupling device based on a multi-machine fuel cell, comprising:

[0034] The acquisition module is used to collect the sum of the actual output power of all fuel cell stacks in the system at the current moment, as well as the user-side electrical load;

[0035] The first output module is used to use the user-side electric load as an input reference value and the sum of the actual output powers of all fuel cell stacks as an input control value, and output the sum of the reference output powers of all fuel cell stacks through a total fuzzy logic PID controller;

[0036] The second output module is used to input the sum of the reference output powers of all fuel cell stacks into the efficiency optimal power allocation model, and output the number of fuel cell stacks that need to be started and the corresponding reference output powers;

[0037] The third output module is used to use the reference output power and actual output power value of each fuel cell stack as the input reference value and input control value respectively, output the stack gas flow through the fuzzy logic PID controller of the solenoid valve corresponding to the fuel cell stack, and control the gas flow in the pipeline, so that the actual output power of the fuel cell stack follows the reference output power.

[0038] In a fourth aspect, an embodiment of the present application further provides an electronic device, comprising: at least one memory for storing programs; and at least one processor for executing the programs stored in the memory. When the program stored in the memory is executed, the processor is used to execute the method described in the first aspect or any possible implementation of the first aspect.

[0039] In a fifth aspect, an embodiment of the present application further provides a computer-readable storage medium, which stores a computer program. When the computer program runs on a processor, the processor executes the method described in the first aspect or any possible implementation of the first aspect.

[0040] In a sixth aspect, an embodiment of the present application further provides a computer program product, which, when executed on a processor, enables the processor to execute the method described in the first aspect or any possible implementation manner of the first aspect.

[0041] The hydrogen-electric-thermal multi-energy coupling method and system based on multi-machine fuel cells provided in the embodiments of the present application ensure that the multi-machine fuel cells always output at the maximum efficiency under the current power through the efficiency-optimal power allocation model, reduce the loss of the fuel cell in the low power range, avoid the long-term operation of a single fuel cell stack at rated power or high power, and improve the flexibility and stability of the system; fuzzy logic PID controller is used in each control link of the hydrogen-electric-thermal multi-energy coupling system to improve the rapidity of the system response, ensure that the system accurately tracks the changes in the user-side electrical load and adjusts the output power in time.

[0042] In some embodiments, by comparing the amount of waste heat recovered at the current moment and the size of the heat load on the user side, the waste heat priority principle is used to control whether the hydrogen burner is working at the current moment and whether the hot water storage tank releases the stored heat to the outside. The hot water storage tank is used to centrally manage the heat of the hydrogen-electric-thermal multi-energy coupling system based on the waste heat priority principle, thereby increasing the total amount of waste heat recovery in the system, ensuring that the waste heat is utilized in a timely manner, and reducing the hydrogen consumption of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the present application or related technologies, the following is a brief introduction to the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0044] Figure 1 It is a schematic diagram of the architecture of a hydrogen-electric-thermal multi-energy coupling system based on a multi-machine fuel cell provided in an embodiment of the present application;

[0045] Figure 2 This is one of the flow diagrams of the hydrogen-electric-thermal multi-energy coupling method based on a multi-machine fuel cell provided in an embodiment of the present application;

[0046] Figure 3 This is the second flow chart of the hydrogen-electric-thermal multi-energy coupling method based on a multi-machine fuel cell provided in an embodiment of the present application;

[0047] Figure 4 It is a schematic diagram of power efficiency curves of multiple fuel cell stacks provided in an embodiment of the present application under the principle of average power distribution;

[0048] Figure 5 It is a schematic diagram of a power efficiency curve under the efficiency-optimal power allocation strategy provided in an embodiment of the present application;

[0049] Figure 6 It is a schematic diagram comparing the actual output power and electrical load of the system for 24 hours provided in the embodiment of the present application;

[0050] Figure 7 This is a schematic diagram of the changes in 24-hour waste heat recovery provided in an embodiment of the present application;

[0051] Figure 8 This is a schematic diagram of the changes in 24-hour external heating provided by the embodiment of the present application;

[0052] Fig. 9 It is a structural schematic diagram of a hydrogen-electric-thermal multi-energy coupling device based on a multi-machine fuel cell provided in an embodiment of the present application. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0054] Figure 1 Schematic diagram of the architecture of a hydrogen-electric-thermal multi-energy coupling system based on a multi-machine fuel cell provided in an embodiment of the present application, such as Figure 1 As shown, the system at least includes:

[0055] A plurality of fuel cell stacks 1 connected in parallel Figure 1 3 are shown in the figure), an air compressor 21, a hydrogen compressor 22, an intercooler 3, a hydrogen storage tank 4, a hydrogen mixing tank 5 and a hot water storage tank 9.

[0056] The air compressor 21 compresses the incoming air. The compressed air has a very high temperature and is cooled to the stack inlet temperature through the intercooler 3. It then enters each fuel cell stack 1 through the air solenoid valve 71. The unreacted air discharged from the fuel cell stack 1 is heated due to the electrochemical reaction of the stack and can be used to preheat the hydrogen in the hydrogen mixing tank 5.

[0057] Normal temperature water enters the intercooler 3 through the first water pump 61 to cool the high temperature air entering the intercooler 3 , and the heated water enters the hot water storage tank 9 for storage.

[0058] The hydrogen storage tank 4 is configured to store new hydrogen, which is mixed with unreacted hydrogen discharged from the fuel cell stack 1 in the hydrogen mixing tank 5 and then enters the fuel cell stack 1 through the hydrogen solenoid valve 72 .

[0059] Optionally, the unreacted hydrogen discharged from the fuel cell stack 1 is compressed by the hydrogen compressor 22 and enters the hydrogen mixing tank 5 to be used for the next round of electrochemical reaction of the stack.

[0060] The hot water generated by the electrochemical reaction of the fuel cell stack 1 enters the hot water storage tank 9 for storage. At the same time, the hot water storage tank 9 provides water with a temperature lower than the stack outlet temperature to the fuel cell stack 1 through the second water pump 62 to remove the stack waste heat. The heated water enters the hot water storage tank 9 again.

[0061] Optionally, each fuel cell stack 1 is connected to an air solenoid valve 71, a hydrogen solenoid valve 72 and a second water pump 62. Alternatively, air or hydrogen is introduced into different fuel cell stacks 1 through a multi-way valve.

[0062] Optionally, in order to ensure that the water provided by the hot water storage tank 9 to the fuel cell stack 1 through the second water pump 62 is lower than the stack outlet temperature, normal temperature water enters the hot water storage tank 9 through the third water pump 63 to lower its temperature.

[0063] Optionally, each fuel cell stack is connected to a DC / DC converter configured to adjust the output voltage of the fuel cell.

[0064] Optionally, the system further comprises a hydrogen burner 8. When the hot water in the hot water storage tank 9 is insufficient to meet the heat load on the user side of the light source, normal temperature water enters the hydrogen burner 8 through the fourth water pump 64, and the hydrogen in the hydrogen storage tank 4 enters the hydrogen burner 8 through the connected hydrogen solenoid valve 72 for combustion and heating, and the heated high temperature water enters the hot water storage tank 9 to supplement the heat supply.

[0065] Figure 2 This is one of the flow diagrams of the hydrogen-electric-thermal multi-energy coupling method based on a multi-machine fuel cell provided in the embodiment of the present application, such as Figure 2 As shown, this method is Figure 1 The system implementation shown in the figure includes at least the following steps:

[0066] S201. Collect the sum of the actual output power of all fuel cell stacks in the system at the current moment, as well as the user-side electrical load.

[0067] S202, taking the user-side electric load as the input reference value and the sum of the actual output powers of all fuel cell stacks as the input control value, outputting the sum of the reference output powers of all fuel cell stacks through the total fuzzy logic PID controller.

[0068] Specifically, the Proportional Integration Differentiation (PID) controller continuously compares the deviation between the actual output value of the system and the reference input value, and adjusts the control input according to this deviation to make the system output as close to the reference input value as possible; it can achieve control of system parameters.

[0069] Collect the actual output power sum of all fuel cell stacks in the system at the current moment, the auxiliary power, and the user-side electrical load. The auxiliary power refers to the sum of the power consumed by the operation of other equipment other than the fuel cell stack in the hydrogen-electric-thermal multi-energy coupling system based on multiple fuel cells.

[0070] The actual output power of the system is the sum of the actual output power of all fuel cell stacks in the system minus the auxiliary power.

[0071] The current user-side electric load is used as the input reference value, and the actual output power of all fuel cell stacks is used as the input control value (also called feedback value). The total fuzzy logic PID controller outputs the sum of the reference output powers of all fuel cell stacks W. MFC .

[0072] S203, inputting the sum of the reference output powers of all fuel cell stacks into the efficiency-optimized power allocation model, and outputting the number of fuel cell stacks that need to be started and the corresponding reference output powers.

[0073] Specifically, the sum of the reference output powers of all fuel cell stacks in the system output by the total fuzzy logic PID controller is W MFC As input, the efficiency optimal power allocation model is used to calculate offline the number of fuel cell stacks that need to be started and the corresponding reference output power.

[0074] The number of fuel cell stacks that need to be started calculated offline using the efficiency optimal power allocation model may be smaller than the number of fuel cell stacks in the system, that is, some fuel cell stacks may not be started.

[0075] The efficiency-optimal power allocation model can determine in real time whether it is necessary to start additional fuel cell stacks to increase output power. After determining the number of fuel cell stacks that need to be started, the overall efficiency is optimal when the output power of each fuel cell stack is equal.

[0076] S204, using the reference output power and actual output power value of each fuel cell stack as the input reference value and input control value respectively, outputting the stack gas flow through the fuzzy logic PID controller of the solenoid valve corresponding to the fuel cell stack, and controlling the gas flow of the pipeline.

[0077] Specifically, the input reference value of the fuzzy logic PID controller is the reference output power of the corresponding fuel cell stack, the input control value is the actual output power of the fuel cell stack, and the output value is the gas flow rate of the pipeline where the fuel cell stack is located.

[0078] The reference output power of different fuel cell stacks is input into the fuzzy logic PID controller of the corresponding stack solenoid valve. If the corresponding fuel cell stack needs to be started, the fuzzy logic PID controller uses the reference output power calculated in S203 as input; if the corresponding fuel cell stack does not need to be started, the default input reference output power value is 0.

[0079] The fuzzy logic PID controller controls the gas flow rate in the pipeline based on the input reference output power of the fuel cell stack, so that the actual output power of the fuel cell stack changes with the reference output power.

[0080] Optionally, the solenoid valve / water pump can control the flow rate of gas / water in the pipeline where it is located, and the control signal is sent by a fuzzy logic PID controller.

[0081] The hydrogen-electric-thermal multi-energy coupling method based on multi-machine fuel cells provided in the embodiment of the present application takes the current user-side electric load as the input reference value, the sum of the actual output powers of all fuel cell stacks in the system as the input control value, and uses the total fuzzy logic PID controller to determine the sum of the reference output powers of all fuel cell stacks in the system to ensure that the system meets the energy supply requirements; then, the sum of the reference output powers of all fuel cell stacks in the system is used as input, and the efficiency-optimal power allocation model is used to obtain the number of fuel cell stacks that need to be started in the system and the corresponding reference output powers, while achieving the minimum number of fuel cell stacks started and the optimal efficiency; then, the reference output power and actual output power of a single fuel cell stack output by the model are used as the input reference value and input control value, respectively, to control the gas flow in the pipeline where each fuel cell stack is located, so that the actual output power of the fuel cell stack changes with the reference output power.

[0082] This application ensures that the multi-machine fuel cell always outputs at the maximum efficiency under the current power, reduces the loss of the fuel cell in the low power range, avoids the long-term operation of a single fuel cell stack at rated power or high power, and improves the flexibility and stability of the system; the fuzzy logic PID controller is used in each control link of the hydrogen-electric-thermal multi-energy coupling system to improve the rapidity of the system response, ensure that the system accurately tracks the changes in the user-side electrical load, and adjusts the output power in time.

[0083] Optionally, S203 specifically includes:

[0084] Output the number of fuel cell stacks that need to be started and the corresponding reference output power, including:

[0085] The system efficiency is optimal when the output power of different fuel cell stacks is the same;

[0086] When the efficiency of starting up n+1 fuel cell stacks is equal to the efficiency of starting up n fuel cell stacks, the power corresponding to the intersection of the power efficiency curves of the average power distribution of n+1 fuel cell stacks and the average power distribution of n fuel cell stacks is determined to be W. tn ;

[0087] If the sum of the reference output powers of all fuel cell stacks is greater than W tn , then determine the power W corresponding to the intersection of the power efficiency curves under the conditions of average power distribution of n+2 fuel cell stacks and average power distribution of n+1 fuel cell stacks t(n+1) and compared with the sum of the reference output powers of all fuel cell stacks;

[0088] If the sum of the reference output powers of all fuel cell stacks is less than or equal to W tn , then the number of fuel cell stacks that need to be started is n, and the reference output power of the n fuel cell stacks is calculated based on the principle of average power distribution.

[0089] Specifically, in S203, when different fuel cell stacks in the system operate at the same output power, the system efficiency is considered to be optimal, and under this principle, the number of fuel cell stacks that need to be started and the corresponding reference output power are output.

[0090] When there are n fuel cell stacks in the system operating on the principle of average power distribution, the corresponding power efficiency curve can be obtained; when there are n+1 fuel cell stacks in the system operating on the principle of average power distribution, the corresponding power efficiency curve can also be obtained. There is an intersection point W between the two power efficiency curves. tn , at the intersection, the efficiency of n fuel cell stacks and n+1 fuel cell stacks are the same. Then, it is further determined whether the power demand of the system can be met to determine how many fuel cell stacks need to be started.

[0091] If W tn Less than the sum of the reference output powers W of all fuel cell stacks of the total fuzzy logic PID controller in S202 MFC , it means that starting n fuel cell stacks cannot meet the output power demand of the system. It is necessary to further determine whether starting n+1 fuel cell stacks can meet the output power demand of the system, and further determine the power W corresponding to the intersection of the power efficiency curves under the conditions of average power distribution of n+2 fuel cell stacks and average power distribution of n+1 fuel cell stacks. t(n+1) With W MFC The size between.

[0092] If W tn Greater than or equal to the sum of the reference output powers W of all fuel cell stacks of the total fuzzy logic PID controller in S202MFC , it means that starting n fuel cell stacks can meet the output power demand of the system, the number of fuel cell stacks that need to be started is n, and the reference output power W of n fuel cell stacks is calculated based on the power allocation principle FC,n , specifically:

[0093] W MFC ≤W tn

[0094] The hydrogen-electric-thermal multi-energy coupling method based on multi-machine fuel cells provided in the embodiment of the present application ensures that the multi-machine fuel cells always output at the maximum efficiency under the current power, reduces the loss of the fuel cells in the low power range, avoids the long-term operation of a single fuel cell stack at rated power or high power, and improves the flexibility and stability of the system.

[0095] In some embodiments, the method further comprises:

[0096] Compare the waste heat recovery heat and the heat load on the user side at the current moment, and control whether the hydrogen burner 8 is working and whether the hot water storage tank 9 releases the stored heat to the outside at the current moment based on the waste heat priority principle.

[0097] Specifically, the user-side heat load refers to the amount of heat required to maintain the thermal balance of the room per unit time, and the user-side electric load refers to the total amount of electric power drawn from the power system by the electric energy user's electrical equipment at a certain moment. Generally speaking, the user-side electric load is greater than or equal to the user-side heat load. In the process of energy supply, the user's heat load is mainly considered.

[0098] Compare the waste heat recovery heat of the system and the heat load on the user side, and control whether the hydrogen burner 8 is working and whether the hot water storage tank 9 releases the stored heat to the outside at the current moment based on the waste heat priority principle. When the waste heat recovery heat is not enough to supply the heat load on the user side, consider using the hydrogen burner 8 or the hot water storage tank 9 for supplementary heating.

[0099] In some embodiments, the waste heat priority principle is used to control whether the hydrogen burner 8 is working at the current moment and whether the hot water storage tank 9 releases the stored heat externally, specifically including:

[0100] If the waste heat recovery heat is greater than or equal to the user-side heat load, the waste heat recovery heat is used for heating alone, and any excess heat is stored in the hot water storage tank 9;

[0101] If the waste heat recovery heat is less than the user-side heat load, it is determined whether the hot water storage tank 9 has heat storage. If so, the hot water storage tank 9 is used for supplementary heating;

[0102] If the hot water storage tank 9 does not store heat or does not store enough heat, the hydrogen burner 8 is operated to provide additional heat.

[0103] Specifically, the priorities of waste heat recovery, heating by the hot water storage tank 9 and heating by the hydrogen burner 8 are: waste heat recovery takes precedence over the hot water storage tank 9 which takes precedence over the hydrogen burner 8 .

[0104] Compare the waste heat recovery heat and the heat load on the user side at the current moment. When the waste heat recovery heat is sufficient to supply the heat load on the user side, that is, the waste heat recovery heat is greater than or equal to the heat load on the user side, the waste heat recovery heat is used alone for heating, and the excess is stored in the hot water storage tank 9.

[0105] When the heat recovered from waste heat is insufficient to supply the heat load on the user side, that is, the heat load on the user side is greater than the heat recovered from waste heat, it is determined whether there is heat storage in the hot water storage tank 9. If there is, the hot water storage tank 9 releases the stored hot water for supplementary heating. If there is no heat or the heat stored in the hot water storage tank 9 cannot fully supply the heat load on the user side, the hydrogen burner 8 works to provide supplementary heating. After the heat load on the user side is met, the next moment is entered.

[0106] Optionally, waste heat recovery includes the hot water storage tank 9 providing water with a temperature lower than the stack outlet temperature to each fuel cell stack 1 through the second water pump 62 to carry away the stack waste heat, the intercooler 3 cooling the high-temperature air to discharge the heat of the hot water, and the heat of the hot water generated by the electrochemical reaction of the fuel cell stack 1.

[0107] The hydrogen-electric-thermal multi-energy coupling method based on multi-machine fuel cells provided in the embodiment of the present application finally compares the waste heat recovery heat at the current moment and the size of the user-side heat load, and controls whether the hydrogen burner is working at the current moment and whether the hot water storage tank releases the stored heat to the outside based on the waste heat priority principle. The heat of the hydrogen-electric-thermal multi-energy coupling system is centrally managed by the hot water storage tank based on the waste heat priority principle, thereby increasing the total amount of waste heat recovery in the system, ensuring that the waste heat is utilized in a timely manner, and reducing the hydrogen consumption of the system.

[0108] The technical solution provided in the embodiment of the present application is further illustrated below by using a specific example.

[0109] Figure 3 This is the second flow chart of the hydrogen-electric-thermal multi-energy coupling method based on a multi-machine fuel cell provided in the embodiment of the present application, such as Figure 3 As shown, the fuel cell stack is referred to as a stack for short. Taking the stack 3 included in the system as an example, the method at least includes:

[0110] S1. Collect the current user-side electrical load, the actual output power of all fuel cells, and the auxiliary power of the hydrogen-electric-thermal multi-energy coupling system, and calculate the sum of the reference output power of all fuel cells in the total fuzzy logic PID controller.

[0111] S2. The sum of the reference output powers of all the battery stacks is input into the efficiency-optimal power allocation strategy, and the number k of battery stacks that need to be started and the reference output powers of the k battery stacks are obtained through offline calculation.

[0112] Figure 4 is a schematic diagram of a power efficiency curve of multiple fuel cell stacks provided in an embodiment of the present application under the principle of average power distribution, Figure 5 is a schematic diagram of a power efficiency curve under the efficiency-optimized power allocation strategy provided in an embodiment of the present application, such as Figure 4 and Figure 5 As shown, there are a total of 3 fuel cell stacks in the system. When 1, 2 or 3 fuel cell stacks in the system operate on the principle of average power distribution, there are 3 power efficiency curves, and the 3 power efficiency curves have 2 intersection points.

[0113] When there are 1 or 2 fuel cell stacks in the system operating on the principle of equal power distribution, the intersection of the power efficiency curve is W t1 When there are 2 or 3 fuel cell stacks in the system operating on the principle of average power distribution, the intersection of the power efficiency curve is W t2 .

[0114] If W t1 Less than W MFC , it means that further judgment of W is needed t2 and W MFC The size between t2 Greater than or equal to W MFC , it means that the two fuel cell stacks can meet the power demand of the system by operating on the principle of even power distribution; otherwise, the third fuel cell stack needs to be started further.

[0115] S3. Input the reference output power of different fuel cells into the fuzzy logic PID controller of the corresponding fuel cell solenoid valve to change the gas flow in the fuel cell so that the actual output power of the fuel cell follows the reference power. The change in the actual output power of the fuel cell brings about heat generation and temperature changes in the stack, and the second water pump changes the cooling water flow to stabilize the temperature in the stack.

[0116] S4. Compare the current waste heat recovery heat and the user-side heat load, and decide whether the hydrogen burner 8 is working and whether the hot water storage tank 9 releases the stored heat to the outside according to the principle of waste heat priority.

[0117] When the waste heat recovery heat is greater than or equal to the user-side heat load, the waste heat recovery heat is used alone for heating, and the excess is stored in the hot water storage tank 9.

[0118] When the heat recovered from waste heat is less than the heat load on the user side, it is further determined whether there is heat storage in the hot water storage tank 9. If so, the hot water storage tank 9 releases the stored hot water for supplementary heating. If there is no heat storage or the heat storage in the hot water storage tank 9 cannot fully supply the heat load on the user side, the hydrogen burner 8 works to provide supplementary heating.

[0119] S5. The system auxiliary power and the actual output power of k fuel cells change, and the above process is repeated again.

[0120] Figure 6 24 hours system actual output power and electrical load comparison diagram provided in the embodiment of the present application, such as Figure 6 As shown, the system output power accurately tracks the user-side electrical load, with a maximum error of only 1.5%.

[0121] Figure 7 It is a schematic diagram of the change of 24-hour waste heat recovery provided by the embodiment of the present application. The waste heat recovery heat includes the waste heat of the stack taken away by the water below the outlet temperature of the stack provided by the hot water storage tank 9 through the second water pump 62 to the k stacks, the heat of the hot water discharged by the intercooler 3 cooling the high-temperature air, and the heat of the hot water generated by the electrochemical reaction of the k stacks. It does not only include the heat of the hot water generated by the electrochemical reaction of the k stacks.

[0122] Figure 8 24-hour external heating change diagram provided in the embodiment of the present application, such as Figure 8 As shown, the system supplies external heat according to the principle of priority utilization of waste heat. Assume that at 0:00, the net heat storage capacity of the hot water storage tank 9 is 0. From 0:00 to 6:30, the waste heat recovered by the system is less than the heat load, and the hydrogen burner 8 burns hydrogen to supplement the heat. As the waste heat gradually increases, the hydrogen combustion gradually decreases. From 6:30 to 8:45, the waste heat is greater than the heat load, the hydrogen combustion stops, and the hot water storage tank 9 supplies heat independently. The excess waste heat is stored in the hot water storage tank 9 and reaches a peak of 11.26 kWh at 8:45. From 8:45 to 13:21, the waste heat is again less than the heat load, and the hot water storage tank 9 releases the stored heat. At 10:10, the heat stored in the hot water storage tank 9 is used up, and the hydrogen burner 8 burns hydrogen again to supplement the heat. Under the principle of priority utilization of waste heat, the subsequent process is similar. At 20:21, the heat storage in the hot water storage tank 9 reached a peak of 45.78 kWh. At 23:50, the heat storage was exhausted, and the hydrogen burner 8 burned hydrogen again to supplement the heat.

[0123] The hydrogen-electric-thermal multi-energy coupling system and method based on multi-machine fuel cells provided in the embodiments of the present application can improve the electrical efficiency and total waste heat recovery of the hydrogen-electric-thermal multi-energy coupling system, ensure that the system accurately tracks the changes in the user-side electrical load, and that the system waste heat is used in a timely manner. It can be well applied to multi-machine fuel cells in hydrogen-electric-thermal multi-energy coupling situations.

[0124] Fig. 9 is a schematic diagram of the structure of a hydrogen-electric-thermal multi-energy coupling device based on a multi-machine fuel cell provided in an embodiment of the present application, such as Fig. 9 As shown, the device at least includes:

[0125] The collection module 901 is used to collect the sum of the actual output power of all fuel cell stacks in the system at the current moment, as well as the user-side electrical load;

[0126] The first output module 902 is used to use the user-side electric load as an input reference value and the sum of the actual output powers of all fuel cell stacks as an input control value, and output the sum of the reference output powers of all fuel cell stacks through a total fuzzy logic PID controller;

[0127] The second output module 903 is used to input the sum of the reference output powers of all fuel cell stacks into the efficiency optimal power allocation model, and output the number of fuel cell stacks that need to be started and the corresponding reference output powers;

[0128] The third output module 904 is used to use the reference output power and actual output power value of each fuel cell stack as the input reference value and input control value respectively, output the stack gas flow through the fuzzy logic PID controller of the solenoid valve corresponding to the fuel cell stack, and control the gas flow of the pipeline.

[0129] Optionally, the second output module 903 is specifically configured to:

[0130] The system efficiency is optimal when the output power of different fuel cell stacks is the same;

[0131] Determine the power corresponding to the intersection of the power efficiency curves under the condition of average power distribution of n+1 fuel cell stacks and average power distribution of n fuel cell stacks as W tn ;

[0132] If W tn If the power W is less than the sum of the reference output powers of all fuel cell stacks, then the power W corresponding to the intersection of the power efficiency curves under the conditions of the average power distribution of n+2 fuel cell stacks and the average power distribution of n+1 fuel cell stacks is determined. t(n+1) and compared with the sum of the reference output powers of all fuel cell stacks;

[0133] If W tn If the reference output power is greater than or equal to the sum of the reference output powers of all fuel cell stacks, the number of fuel cell stacks that need to be started is n, and the reference output power of the n fuel cell stacks is calculated based on the principle of average power distribution.

[0134] Optionally, the device further comprises:

[0135] The heating control module is used to compare the waste heat recovery heat and the heat load on the user side at the current moment, and control whether the hydrogen burner is working and whether the hot water storage tank releases the stored heat to the outside at the current moment based on the waste heat priority principle.

[0136] Optionally, the heating control module is specifically used for:

[0137] If the waste heat recovery heat is greater than or equal to the user-side heat load, the waste heat recovery heat will be used for heating alone, and any excess heat will be stored in a hot water storage tank;

[0138] If the waste heat recovery heat is less than the user-side heat load, it is determined whether there is heat storage in the hot water storage tank. If so, supplementary heating is provided through the hot water storage tank.

[0139] If the hot water tank does not store heat or does not store enough heat, the hydrogen burner will be used to provide additional heat.

[0140] Optionally, waste heat recovery includes a hot water storage tank providing water with a temperature lower than the stack outlet temperature to each fuel cell stack through a second water pump to carry away the stack waste heat, an intercooler cooling the high-temperature air to discharge the heat of the hot water, and the heat of the hot water generated by the electrochemical reaction of the fuel cell stack.

[0141] Optionally, the actual output power of the system is obtained by subtracting the auxiliary power from the sum of the actual output powers of the n fuel cell stacks.

[0142] It can be understood that the detailed functional implementation of each of the above-mentioned units / modules can be found in the introduction of the aforementioned method embodiment, and will not be repeated here.

[0143] It should be understood that the above-mentioned device is used to execute the method in the above-mentioned embodiment. The implementation principle and technical effect of the corresponding program module in the device are similar to those described in the above-mentioned method. The working process of the device can refer to the corresponding process in the above-mentioned method, which will not be repeated here.

[0144] Based on the method in the above embodiment, an embodiment of the present application provides an electronic device. The device may include: at least one memory for storing programs and at least one processor for executing the programs stored in the memory. When the program stored in the memory is executed, the processor is used to execute the method described in the above embodiment.

[0145] Based on the method in the above embodiment, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program. When the computer program runs on a processor, the processor executes the method in the above embodiment.

[0146] Based on the method in the above embodiment, an embodiment of the present application provides a computer program product. When the computer program product runs on a processor, the processor executes the method in the above embodiment.

[0147] It is understandable that the processor in the embodiment of the present application may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0148] The method steps in the embodiments of the present application can be implemented by hardware, or by a processor executing software instructions. The software instructions can be composed of corresponding software modules, and the software modules can be stored in random access memory (Random Access Memory, RAM), flash memory, read-only memory (Read-Only Memory, ROM), programmable read-only memory (Programmable ROM, PROM), erasable programmable read-only memory (Erasable PROM, EPROM), electrically erasable programmable read-only memory (Electrically EPROM, EEPROM), registers, hard disks, mobile hard disks, CD-ROMs or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and can write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and the storage medium can be located in an ASIC.

[0149] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loading and executing computer program instructions on a computer, the process or function according to the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transmitted by a computer-readable storage medium. The computer instructions can be transmitted from a website site, a computer, a server or a data center to another website site, a computer, a server or a data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server, a data center, etc. that contains one or more available media integrated. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive (SSD)), etc.

[0150] It should be understood that the various numerical numbers involved in the embodiments of the present application are only used for the convenience of description and are not used to limit the scope of the embodiments of the present application.

[0151] It is easy for those skilled in the art to understand that the above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A hydrogen-electric-thermal multi-energy coupling method based on a multi-fuel cell, characterized in that: include: Collect the sum of the actual output power of all fuel cell stacks in the system at the current moment, as well as the user-side electrical load; The user-side electric load is used as an input reference value, the sum of the actual output powers of all the fuel cell stacks is used as an input control value, and the sum of the reference output powers of all the fuel cell stacks is output through a total fuzzy logic PID controller; Inputting the sum of the reference output powers of all the fuel cell stacks into the efficiency optimal power allocation model, and outputting the number of fuel cell stacks that need to be started and the corresponding reference output powers; The reference output power and actual output power value of each fuel cell stack are used as the input reference value and input control value respectively, and the fuzzy logic PID controller of the solenoid valve corresponding to the fuel cell stack outputs the stack gas flow to control the gas flow of the pipeline.

2. The hydrogen-electric-thermal multi-energy coupling method according to claim 1, characterized in that: The output of the number of fuel cell stacks to be started and the corresponding reference output power includes: The system efficiency is optimal when the output power of different fuel cell stacks is the same; Determine the power corresponding to the intersection of the power efficiency curves under the condition of average power distribution of n+1 fuel cell stacks and average power distribution of n fuel cell stacks as W tn ; If W tn If the power W corresponding to the intersection of the power efficiency curves of the average power distribution of n+2 fuel cell stacks and the average power distribution of n+1 fuel cell stacks is less than the sum of the reference output powers of all the fuel cell stacks, then the power W corresponding to the intersection of the power efficiency curves of the average power distribution of n+2 fuel cell stacks and the average power distribution of n+1 fuel cell stacks is determined. t(n+1) and compares it with the sum of the reference output powers of all the fuel cell stacks; If W tn If the reference output power of the fuel cell stacks is greater than or equal to the sum of the reference output powers of all the fuel cell stacks, the number of fuel cell stacks that need to be started is n, and the reference output powers of the n fuel cell stacks are calculated based on the principle of average power distribution.

3. The hydrogen-electric-thermal multi-energy coupling method according to claim 1, characterized in that: The method further comprises: Compare the waste heat recovery heat and the heat load on the user side at the current moment, and control whether the hydrogen burner is working and whether the hot water storage tank releases stored heat to the outside based on the waste heat priority principle.

4. The hydrogen-electric-thermal multi-energy coupling method according to claim 3, characterized in that: The control of whether the hydrogen burner is working and whether the hot water storage tank releases stored heat to the outside at the current moment based on the waste heat priority principle includes: If the waste heat recovery heat is greater than or equal to the user-side heat load, the waste heat recovery heat is used alone for heating, and any excess heat is stored in the hot water storage tank; If the waste heat recovery heat is less than the user-side heat load, it is determined whether the hot water storage tank has heat storage, and if so, the hot water storage tank is used for supplementary heating; If the hot water storage tank does not store heat or does not store enough heat, the hydrogen burner is used to provide additional heat.

5. The hydrogen-electric-thermal multi-energy coupling method according to claim 4, characterized in that: The waste heat recovery heat includes the waste heat of the fuel cell stack that is taken away by the hot water storage tank in the system providing water with a temperature lower than the stack outlet temperature to each fuel cell stack through the second water pump, the heat of the hot water that is discharged by the intercooler cooling the high-temperature air, and the heat of the hot water generated by the electrochemical reaction of the fuel cell stack.

6. The hydrogen-electric-thermal multi-energy coupling method according to claim 1, characterized in that: The actual output power of the system is obtained by subtracting the auxiliary power from the sum of the actual output power of all fuel cell stacks.

7. A hydrogen-electric-thermal multi-energy coupling system based on multi-fuel cells, characterized in that: For the hydrogen-electric-thermal multi-energy coupling method according to any one of claims 1 to 6, the system comprises: a plurality of fuel cell stacks connected in parallel, an air compressor, a hydrogen compressor, an intercooler, a hydrogen storage tank, a hydrogen mixing tank and a hot water storage tank; During the operation of the system, the air compressor compresses the incoming air, which is then cooled to the stack inlet temperature through the intercooler and then enters each fuel cell stack through the air solenoid valve; normal temperature water enters the intercooler through the first water pump to cool the high temperature air, and the heated water enters the hot water storage tank; The hydrogen storage tank is configured to store new hydrogen, which is mixed with unreacted hydrogen discharged from the fuel cell stack in the hydrogen mixing tank and then enters each fuel cell stack through the hydrogen solenoid valve; The hot water generated by the electrochemical reaction of each fuel cell stack enters the hot water storage tank, and the hot water storage tank provides water with a temperature lower than the stack outlet to each fuel cell stack through a second water pump to remove the stack waste heat, and the heated water enters the hot water storage tank again.

8. The hydrogen-electric-thermal multi-energy coupling system according to claim 7 is characterized in that: The system further comprises a hydrogen burner, wherein the hydrogen burner and the hydrogen storage tank are connected via a hydrogen solenoid valve; When the hot water in the hot water storage tank is insufficient to supply the heat load on the user side, normal temperature water enters the hydrogen burner through the fourth water pump, and the hydrogen in the hydrogen storage tank enters the hydrogen burner through the connected hydrogen solenoid valve for combustion and heating, and the heated high-temperature water enters the hot water storage tank to supplement the heating.

9. The hydrogen-electric-thermal multi-energy coupling system according to claim 7, characterized in that: Normal temperature water enters the hot water tank through the third water pump to lower the temperature of the hot water tank, so that the water provided by the hot water tank to each fuel cell stack through the second water pump is lower than the stack outlet temperature.

10. The hydrogen-electric-thermal multi-energy coupling system according to claim 7, characterized in that: The unreacted air discharged from the fuel cell stack is used to preheat the hydrogen in the hydrogen mixing tank; the unreacted hydrogen discharged from the fuel cell stack is compressed by the hydrogen compressor and then enters the hydrogen mixing tank.

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