A Hybrid Hydrogen Production Power Synergy Control Method Based on Temperature-Variable Dynamic Filtering

Abstract

The present invention discloses a hybrid hydrogen production power cooperative control method based on temperature-variable dynamic filtering. After the input power of renewable energy is low-pass filtered, the filtering time constant is adjusted based on the temperature state value of the alkaline solution hydrogen production electrolyzer, so as to control the power of the alkaline solution hydrogen production electrolyzer at the maximum value at this temperature. Through this control method, the advantages of long service life and low operating cost of alkaline solution hydrogen production under long-term operating conditions can be exerted, and the characteristics of fast response speed and wide operating range of PEM hydrogen production can be utilized to improve the flexibility of system regulation, realize the dynamic power distribution between alkaline solution hydrogen production and proton exchange membrane hydrogen production, maximize the utilization rate of alkaline solution hydrogen production, shorten the operating time of the proton exchange membrane electrolyzer, and realize the efficient operation of hybrid hydrogen production.

Description

Technical Field

[0001] The present invention relates to a hybrid hydrogen production power collaborative control method based on temperature-variable dynamic filtering, belonging to the operation control technology of the hydrogen-electric coupling system in the new energy field. Background Art

[0002] Among many new energy sources, hydrogen energy is rich in sources, green and low-carbon. Hydrogen energy is an ideal clean secondary energy source. It is obtained from water, and hydrogen and oxygen are obtained after the electrolysis of water reaction. The reactants after combustion are pure water without any pollution. Therefore, it fully meets the requirements of low-carbon environmental protection. Developing renewable energy hydrogen production is of great significance for building a clean, low-carbon, safe and efficient energy system.

[0003] However, renewable energy electrolytic hydrogen production faces many problems. Due to the intermittent, fluctuating and random characteristics of renewable energy, single-form hydrogen production cannot meet the requirements. Therefore, the hybrid hydrogen production mode of alkaline hydrogen production and proton exchange membrane hydrogen production has become a promising solution. However, there are differences in the response speed, life cycle and gas production efficiency of different types of hydrogen production. Therefore, it is urgent to find a control method suitable for hybrid hydrogen production. Summary of the Invention

[0004] The purpose of the present invention is to provide a hybrid hydrogen production power collaborative control method based on temperature-variable dynamic filtering for the deficiencies of the existing technology. The present invention solves the problems of slow response speed of hybrid hydrogen production, short service life of equipment, inflexible regulation, and difficulty in long-term stable and efficient operation of the hybrid hydrogen production system, so that hybrid hydrogen production can operate efficiently under different working conditions.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] A hybrid hydrogen production power collaborative control method based on temperature-variable dynamic filtering uses renewable energy power generation for hybrid hydrogen production. Hybrid hydrogen production includes alkaline hydrogen production and proton exchange membrane hydrogen production; during hybrid hydrogen production, the temperature of the alkaline hydrogen production electrolyzer at time t is obtained in real time, and based on temperature-variable dynamic filtering, power collaborative control is performed on hybrid hydrogen production, where the output value of the renewable energy power generation power at time t after low-pass filtering is used as the reference value of the power consumption of alkaline hydrogen production at time t

[0007]

[0008] The reference value of the power consumption of proton exchange membrane hydrogen production at time t

[0009]

[0010] T i (t) = -k·c(t) + b, k, b > 0

[0011] Among them, P in (t) is the renewable energy power generation, and T d is the calculation period, and T i (t) is the variable filtering time constant based on the temperature state value of the alkaline hydrogen production electrolyzer. c(t) represents the temperature of the alkaline hydrogen production electrolyzer at time t, and both k and b are empirical coefficients.

[0012] Furthermore, the values of the empirical coefficients k and b are obtained through the following method:

[0013] When the temperature c(t) of the alkaline hydrogen production electrolyzer is the rated operating temperature c p of the electrolyzer, the filtering time constant T i is 0; when the temperature c(t) of the alkaline hydrogen production electrolyzer is the initial temperature c i in the cold start stage, the filtering time constant T i is the cold start time t pmax of the alkaline hydrogen production electrolyzer. Substitute these two conditions into the variable filtering time constant formula respectively, and solve the equations simultaneously to obtain the values of the empirical coefficients k and b.

[0014] Furthermore, the initial temperature c i and the cold start time t pmax of the electrolyzer are obtained through the following method:

[0015] The initial temperature c i in the cold start stage is obtained by measuring the temperature of the electrolyzer before the alkaline hydrogen production electrolyzer is started;

[0016] The cold start time t pmax of the alkaline hydrogen production electrolyzer is obtained by measuring the time required for the alkaline hydrogen production to step from a power of 0 to the rated power value P i when the initial temperature of the alkaline hydrogen production electrolyzer is c max under the constraints of the maximum voltage and the maximum current, and this time is t pmax .

[0017] Furthermore, the maximum voltage constraint is

[0018] U max = N·U cell

[0019] where N is the number of series-connected electrolysis cells in the alkaline hydrogen production electrolyzer, and U cell is the maximum voltage of the electrolysis cell.

[0020] Furthermore, the maximum current constraint is

[0021] I max = S·σ max

[0022] where σ max is the maximum current density of the alkaline hydrogen production electrolyzer, and S is the plate area of the alkaline hydrogen production electrolyzer.

[0023] When the alkaline hydrogen production electrolyzer reaches the maximum voltage or maximum current, the power of the alkaline hydrogen production electrolyzer at this time is the maximum power. Further, the renewable energy power generation is wind power generation, photovoltaic power generation or hydropower generation.

[0024] A hybrid hydrogen production device based on temperature-variable dynamic filtering includes: an alkaline hydrogen production device, a proton exchange membrane hydrogen production device and a controller; the controller obtains the temperature of the alkaline hydrogen production electrolyzer at time t in real time, and based on temperature-variable dynamic filtering, performs power coordination control on hybrid hydrogen production, where the output value of the renewable energy power generation power at time t after low-pass filtering is used as the reference value of the alkaline hydrogen production consumption power at time t

[0025]

[0026] The reference value of the proton exchange membrane hydrogen production consumption power at time t

[0027]

[0028] T i (t) = -k·c(t) + b, k, b > 0

[0029] where, P in (t) is the renewable energy power generation power, T d is the calculation period, T i (t) is the variable filtering time constant based on the temperature state value of the alkaline hydrogen production electrolyzer, c(t) represents the temperature of the alkaline hydrogen production electrolyzer at time t, and both k and b are empirical coefficients.

[0030] The beneficial effects of the present invention are: Based on the control strategy proposed by the present invention for hybrid hydrogen production, it can not only give play to the advantages of long service life and low cost of alkaline solution hydrogen production under long-term operating conditions, but also utilize the characteristics of fast response speed and wide operating range of PEM hydrogen production to improve the flexibility of system regulation, thereby fully tapping the accommodation potential of different hydrogen production systems, improving the matching of the hybrid hydrogen production system with renewable energy with fast and large-scale power fluctuations, and realizing long-term stable and efficient operation of the hybrid hydrogen production system. Description of the Drawings

[0031] Figure 1 It is a schematic diagram of renewable energy power generation hybrid hydrogen production provided by this application;

[0032] Figure 2 It is a block diagram of the control method provided by this application; Detailed implementation mode

[0033] The present invention proposes a hybrid hydrogen production power cooperative control method based on temperature-variable dynamic filtering, which can achieve rapid response of hybrid hydrogen production under different working conditions and realize stable and efficient operation of the system. As Figure 1 shown, renewable energy power generation is used for hybrid hydrogen production, and hybrid hydrogen production includes alkaline hydrogen production and proton exchange membrane hydrogen production.

[0034] Among them, the renewable energy power generation power is completely absorbed by alkaline hydrogen production and proton exchange membrane hydrogen production, that is, P in (t) = P AWE (t) + P PEM (t)

[0035] Among them, P in is the renewable energy power generation power, P AWE is the alkaline hydrogen production consumption power, and P PEM is the proton exchange membrane hydrogen production consumption power.

[0036] As Figure 2 shown, when hybrid hydrogen production is carried out, the output value of the renewable energy power generation power after low-pass filtering is used as the reference value of the alkaline hydrogen production consumption power

[0037]

[0038] Among them, is the reference value of the alkaline hydrogen production consumption power, T i is the variable filtering time constant based on the temperature state value of the alkaline hydrogen production electrolyzer, and s is the Laplace operator.

[0039] The reference value of the proton exchange membrane hydrogen production consumption power

[0040]

[0041] Among them, is the reference value of the proton exchange membrane hydrogen production consumption power.

[0042] Through discretization, it is transformed into a difference equation. By real-time obtaining the temperature of the alkaline hydrogen production electrolyzer and the renewable energy power generation power at time t, based on temperature-variable dynamic filtering, power cooperative control of hybrid hydrogen production is carried out. Among them, the reference value of the alkaline hydrogen production power at time t is the output value of the renewable energy power generation power at time t after low-pass filtering, that is

[0043]

[0044] Among them, is the reference value of the alkaline hydrogen production consumption power at time t, is the reference value of power consumption of alkaline hydrogen production at time t-1, T i (t) is the variable filter time constant based on the temperature state value of the alkaline hydrogen production electrolyzer, T d The calculation period can be set and adjusted according to actual conditions, and can generally be set to >0.5*10e-6s.

[0045] The reference value of the power consumption of proton exchange membrane hydrogen production is

[0046]

[0047] in, is the reference value of power consumption for hydrogen production by proton exchange membrane, It is the reference value of the power consumption of proton exchange membrane hydrogen production at time t-1.

[0048] Filter time constant T i is a time variable, and its value changes with the temperature c of the alkaline hydrogen production electrolyzer, and the change rule is T i (t)=-k·c(t)+b, k, b>0

[0049] Among them, k and b are empirical coefficients, which are obtained by combining the parameters under certain conditions. Specifically:

[0050] When the alkaline hydrogen production electrolyzer temperature c(t) is the rated operating temperature c p When the filter time constant T i is 0; when the alkaline hydrogen production electrolyzer temperature c(t) is the cold start initial temperature c i , filter time constant T i is the cold start time t of alkaline hydrogen production electrolyzer pmax Substitute the above conditions into the variable filter time constant formula, and then solve them together to obtain the values ​​of the empirical coefficients k and b.

[0051] Rated working temperature of electrolytic cell c p , obtained from data provided by the electrolyzer manufacturer.

[0052] The initial cold start temperature of the electrolyzer c i and electrolyzer cold start time t pmax , obtained by the following method:

[0053] Initial temperature of cold start phase c i The temperature of the electrolytic cell before the electrolytic cell is turned on is measured and recorded as the initial temperature c i .

[0054] Cold start time t of alkaline hydrogen production electrolyzer pmax When the initial temperature of the alkaline hydrogen production electrolyzer is c i, under the limitations of the maximum voltage constraint and the maximum current constraint, measure the time required for alkaline hydrogen production to step from a power of 0 to the rated power value P max and denote it as t pmax .

[0055] The methods for obtaining the maximum voltage constraint value and the maximum current constraint value are as follows:

[0056] If the electrolyzer is composed of series-connected electrolytic cells, then the maximum voltage constraint U max is

[0057] U max = N·U cell

[0058] where N is the number of series-connected electrolytic cells, and U cell is the maximum voltage of the electrolytic cell, generally 2V.

[0059] The maximum current constraint I max is

[0060] I max = S·σ max

[0061] where σ max is the maximum current density of the electrolyzer, and S is the plate area of the electrolyzer.

[0062] When the alkaline hydrogen production electrolyzer reaches the maximum voltage or the maximum current, the power of the alkaline hydrogen production electrolyzer at this time is the maximum power.

[0063] In the present invention, after the input power of renewable energy is low-pass filtered, the filtering time constant is adjusted based on the temperature state value of the alkaline solution hydrogen production electrolyzer, so as to control the power of the alkaline solution hydrogen production electrolyzer at the maximum value at this temperature. Through this control method, the advantages of long service life and low operating cost of alkaline solution hydrogen production under long-term operating conditions can be exerted, and the characteristics of fast response speed and wide operating range of PEM hydrogen production can be utilized to improve the flexibility of system regulation, realize the dynamic power distribution between alkaline solution hydrogen production and proton exchange membrane hydrogen production, maximize the utilization rate of alkaline solution hydrogen production, shorten the operating time of the proton exchange membrane electrolyzer, and achieve the efficient operation of hybrid hydrogen production.

[0064] Corresponding to the aforementioned method for power collaborative control of hybrid hydrogen production based on temperature-variable dynamic filtering, the present invention also provides a hybrid hydrogen production device based on temperature-variable dynamic filtering, including: an alkaline hydrogen production device, a proton exchange membrane hydrogen production device, and a controller; the controller obtains the temperature of the alkaline hydrogen production electrolyzer at time t in real time, and performs power collaborative control on hybrid hydrogen production based on temperature-variable dynamic filtering, where the output value of the low-pass filtering of the renewable energy power generation power at time t is used as the reference value of the alkaline hydrogen production consumption power at time t

[0065]

[0066] The difference between the renewable energy power generation at time t and the reference value of the alkaline hydrogen production power consumption at time t is used as the reference value of the proton exchange membrane hydrogen production power consumption at time t+1

[0067]

[0068] T i (t)=-k·c(t)+b, k, b>0

[0069] Among them, P in (t) is the renewable energy power generation, T d is the calculation period, T i (t) is the variable filter time constant based on the temperature state value of the alkaline hydrogen production electrolyzer, c(t) represents the temperature of the alkaline hydrogen production electrolyzer at time t, and both k and b are empirical coefficients.

[0070] Obviously, the above embodiments are only examples for clear illustration and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A hybrid hydrogen production power synergy control method based on temperature-variable dynamic filtering, which uses renewable energy power generation for hybrid hydrogen production. The hybrid hydrogen production includes alkaline hydrogen production and proton exchange membrane hydrogen production; Characterized in that, During hybrid hydrogen production, the temperature of the alkaline hydrogen production electrolyzer at time t is obtained in real time, and power co-control of hybrid hydrogen production is performed based on temperature change dynamic filtering, where the output value of the renewable energy power generation at time t after low-pass filtering is used as the reference value for the alkaline hydrogen production power consumption at time t Reference value of the hydrogen production power consumption of the proton exchange membrane at time t T i (t) = -k·c(t) + b, where k, b > 0 Among them, P in (t) is the renewable energy power generation, T d is the calculation period, T i (t) is the variable filtering time constant based on the temperature state value of the alkaline hydrogen production electrolyzer, c(t) represents the temperature of the alkaline hydrogen production electrolyzer at time t, and both k and b are empirical coefficients.

2. The method according to claim 1, Characterized in that, The values of the empirical coefficients k and b are obtained by the following method: When the temperature c(t) of the alkaline hydrogen production electrolyzer is the rated operating temperature c of the electrolyzer p the filtering time constant T i is 0; The temperature c(t) of the alkaline hydrogen production electrolyzer is the initial temperature c during the cold start phase i When i is the cold start time t of the alkaline hydrogen production electrolyzer pmax Substitute the two conditions into the variable filter time constant formula respectively, and solve the values of the empirical coefficients k and b by simultaneous equations.

3. The method according to claim 2, Characterized in that, Initial temperature c i and the cold start time t of the electrolyzer pmax , are obtained by the following method: Initial temperature c during cold start i Obtained by measuring the electrolyzer temperature before starting the alkaline hydrogen production electrolyzer; Cold start time t of the alkaline hydrogen production electrolyzer pmax When the initial temperature of the alkaline hydrogen production electrolyzer is c i Under the constraints of the maximum voltage and maximum current, measure the time required for the alkaline hydrogen production to step from a power of 0 to the rated power value P max That is t pmax .

4. The method according to claim 3, Characterized in that, The maximum voltage constraint is U max = N·U cell where N is the number of series-connected electrolytic cells in the alkaline hydrogen production electrolyzer, and U cell is the maximum voltage of the electrolytic cell.

5. The method according to claim 3, Characterized in that, The maximum current constraint is I max = S·σ max where σ max is the maximum current density of the alkaline hydrogen production electrolyzer, and S is the plate area of the alkaline hydrogen production electrolyzer.

6. The method according to claim 1, Characterized in that, The renewable energy power generation is wind power generation, photovoltaic power generation or hydroelectric power generation.

7. A hybrid hydrogen production device based on temperature-variable dynamic filtering, Characterized in that, Comprising: Alkaline hydrogen production device, proton exchange membrane hydrogen production device and controller; the controller obtains the temperature of the alkaline hydrogen production electrolytic cell at time t in real time, and performs power co-control on hybrid hydrogen production based on temperature change dynamic filtering, where the output value of the renewable energy power generation power at time t after low-pass filtering is used as the reference value of the alkaline hydrogen production power consumption at time t Reference value of the hydrogen production power consumption of the proton exchange membrane at time t T i (t) = -k·c(t) + b, where k, b > 0 Among them, P in (t) is the renewable energy power generation, T d is the calculation period, T i (t) is the variable filtering time constant based on the temperature state value of the alkaline hydrogen production electrolyzer, c(t) represents the temperature of the alkaline hydrogen production electrolyzer at time t, and both k and b are empirical coefficients.

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