KR102347322B1 - Thermal Management Method and Device For PEFMC - Google Patents

Abstract

The present invention relates to a method and apparatus for controlling cooling of a fuel cell system including a fuel cell stack, and to a flow rate of hydrogen fuel consumed in a fuel cell stack, a low-level calorific value (LHV) of hydrogen, and electric power produced in the fuel cell stack a first step of calculating a minimum amount of cooling required for cooling of the fuel cell stack; a second step of calculating a maximum amount of cooling required for cooling the fuel cell stack from a flow rate of hydrogen fuel consumed in the fuel cell stack, a high calorific value (HHV) of hydrogen, and electric power generated in the fuel cell stack; a third step of controlling the cooling amount of the fuel cell stack so that the cooling amount of the fuel cell stack is within the range of the minimum cooling amount and the maximum cooling amount; It is possible to efficiently and effectively control the cooling of the fuel cell stack.

Description

Fuel cell system cooling control method and device {Thermal Management Method and Device For PEFMC }

The present invention relates to a method and system for controlling cooling of a fuel cell system, and more particularly, to a method and system for controlling cooling of a fuel cell system capable of calculating and controlling an appropriate amount of cooling required for cooling a fuel cell stack during operation of the fuel cell system; It's about the system.

Recently, a hydrogen fuel cell used for electricity production in fields such as automobiles, home or commercial use is a device that generates electrical energy from an electrochemical reaction of hydrogen and oxygen, and the field of use thereof is gradually expanding. Since the hydrogen fuel cell uses hydrogen as a fuel, it has the advantage that it requires little charging time compared to an electric power storage device such as a battery. The electrochemical reaction between hydrogen and oxygen takes place in the fuel cell stack, and in this process, electricity is generated and heat and water are discharged as by-products of the reaction. Among them, since heat increases the temperature of the fuel cell stack and lowers the efficiency of the system, a countermeasure for properly maintaining the temperature of the fuel cell stack is required. PEFMC, also called proton-exchange membrane fuel cell (PEMFC) or polymer electrolyte membrane fuel cell (PEMFC), which is attracting attention recently, has the advantage of high power density and fast operation start. However, for efficient power generation, optimal cooling control is absolutely necessary to prevent the stack temperature rise due to reaction heat and latent heat of water. Accordingly, the fuel cell system includes a device for supplying hydrogen and oxygen to the fuel cell stack as well as a device for cooling.

As a cooling method of a fuel cell system, a water-cooling cooling method in which cooling water is circulated in a fuel cell stack for cooling is widely applied. The cooling rate of the water cooling method may be determined by the temperature and flow rate of the cooling water. Insufficient cooling amount makes the fuel cell stack high temperature and finally dries out, leading to a state in which the fuel cell is stopped. This can lead to very inefficient operation.

The existing cooling control method (Patent Document 001), as disclosed in Korean Patent Publication No. 10-1190729 (2019.10.04.) "Method for predicting coolant flow rate in fuel cell system and method for determining normal circulation of coolant," It has been limited to the extent to which cooling control is performed by measuring the temperature of the cooling water and the like.

Therefore, if the minimum amount of cooling and the maximum amount of cooling that can avoid dry out or flooding of the fuel cell stack can be calculated, efficient and effective cooling control of the fuel cell system is possible.

On the other hand, (Patent Document 002) Korean Patent Publication No. 10-1952792 (2019.02.21.) "Energy system failure diagnosis method and apparatus" applies an exergy-based thermoeconomic method to each component constituting the energy system. Thus, we provide a method and system for diagnosing an energy system failure that can accurately diagnose components with reduced efficiency by calculating the loss day and cost of loss in each component. There is no way to find out the appropriate cooling amount.

Republic of Korea Patent Publication No. 10-1190729 (2019.10.04.) Republic of Korea Patent Publication No. 10-1952792 (2019.02.21.)

Accordingly, the problem to be solved by the present invention is to calculate the minimum amount of cooling and the maximum amount of cooling that can avoid dry out or flooding of the fuel cell stack, and calculate the appropriate amount of cooling for the fuel cell stack. An object of the present invention is to provide a method and system capable of efficiently and effectively controlling cooling of a battery system.

In order to realize the object of the present invention, the method for controlling cooling of a fuel cell system including a fuel cell stack and a fuel cell cooling device according to the present invention includes the flow rate of hydrogen fuel consumed in the fuel cell stack and the low calorific value ( LHV), and a first step of calculating a minimum amount of cooling required for cooling of the fuel cell stack from the power generated by the fuel cell stack; a second step of calculating a maximum amount of cooling required for cooling the fuel cell stack from a flow rate of hydrogen fuel consumed in the fuel cell stack, a high calorific value (HHV) of hydrogen, and electric power generated in the fuel cell stack; and a third step of controlling the cooling amount of the fuel cell stack so that the cooling amount of the fuel cell stack is within the range of the minimum cooling amount and the maximum cooling amount.

에 의하여 연산하는 것을 특징으로 하한다. 여기서,

는 최소냉각량이고,

는 연료전지 스택에서 소비되는 수소의 몰 유량(Mole Flow Rate)이고, LHV는 수소의 저위발열량(Lower Heating Value)이고,

는 연료전지 스택에서 생산되는 전력에 대응되는 엑서지이다.In the first step, the minimum amount of cooling is

It is characterized in that it is calculated by here,

is the minimum amount of cooling,

is the molar flow rate of hydrogen consumed in the fuel cell stack, LHV is the lower heating value of hydrogen,

is an exergy corresponding to power generated by the fuel cell stack.

에 의하여 연산하는 것을 특징으로 한다. 여기서,

는 최대냉각량이고,

는 연료전지 스택에서 소비되는 수소의 몰 유량(Mole Flow Rate)이고, HHV는 수소의 고위발열량(Higher Heating Value)이고,

는 연료전지 스택에서 생산되는 전력에 대응되는 엑서지이다.In the second step, the maximum amount of cooling is

It is characterized in that it is calculated by here,

is the maximum cooling amount,

is the molar flow rate of hydrogen consumed in the fuel cell stack, HHV is the higher heating value of hydrogen,

is an exergy corresponding to power generated by the fuel cell stack.

In the third step, cooling of the fuel cell stack may control the amount of cooling by controlling the temperature and flow rate of the coolant supplied to the fuel cell stack.

Meanwhile, the cooling control apparatus of a fuel cell system including a fuel cell stack according to another embodiment includes a flow rate of hydrogen fuel consumed in the fuel cell stack, a low-level calorific value (LHV) of hydrogen, and electric power produced in the fuel cell stack. A minimum cooling amount calculating unit that calculates the minimum amount of cooling of the fuel cell stack from a maximum cooling amount calculating unit for calculating a maximum cooling amount; and a cooling amount control unit controlling the cooling amount of the fuel cell stack so that the cooling amount of the fuel cell stack is within the range of the minimum cooling amount and the maximum cooling amount. have.

According to the method and system for controlling cooling of a fuel cell system provided by the present invention, the minimum amount of cooling and the maximum amount of cooling capable of avoiding dry out or flooding of the fuel cell stack are calculated and applied to the fuel cell stack. There is an effect that the fuel cell system can be efficiently and effectively cooled and controlled by calculating the appropriate amount of cooling required. The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is a flowchart illustrating a method for controlling cooling of a fuel cell system according to the present invention.
2 is a configuration diagram for explaining a cooling control device of a fuel cell system according to the present invention.
3 is a configuration diagram of a fuel cell system for explaining a cooling control method according to an embodiment of the present invention.

Since the present invention can have various changes and can have various forms, embodiments will be described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention. In describing each figure, like reference numerals have been used for like elements. Terms such as first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms.

The above terms are used only for the purpose of distinguishing one component from another. The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise.

In the present application, terms such as “comprises” or “consisting of” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification is present, but one or more other features It is to be understood that it does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Abbreviations used in the present invention are defined as follows.

: 최소냉각량(Minimum Cooling rate)

: Minimum Cooling rate

: 최대냉각량(Maximum Cooling rate)

: Maximum Cooling rate

: 연료전지 스택에서 소비되는 수소의 몰 유량(Mole Flow Rate)

: Mole flow rate of hydrogen consumed in fuel cell stack

: 연료전지 스택에서 생산되는 전력에 대응되는 엑서지

: Exergy corresponding to power produced by fuel cell stack

_{Water vapor condensation rate ratio (y): The ratio at which water (H 2} O) becomes liquid among by-products of the electrochemical reaction of hydrogen and oxygen produced in the fuel cell stack

LHV: Lower Heating Value of hydrogen

HHV: Higher Heating Value of hydrogen

In the present invention, LHV and HHV mean LHV and HHV for hydrogen unless otherwise specified.

The unit of cooling rate is kJ/h.

On the other hand, parameters that can be controlled by the cooling control device according to the present invention include temperature, pressure, flow rate, etc. of cooling water supplied to a heat exchanger, etc., and the cooling devices capable of changing these cooling parameters are controlled by the cooling control device of the present invention. can be a possible target.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the drawings.

Before describing the cooling control method of the present invention, a configuration diagram of the fuel cell system of FIG. 3 to which an embodiment of the present invention can be applied will be described.

3 shows the configuration of a fuel cell system for generating electric energy from an electrochemical reaction of hydrogen and oxygen.

Referring to FIG. 3, components of the fuel cell system include an air blower (1), a humidifier (2), a fuel cell stack (FCS, Fuel Cell Stack) (6), and an anode (3). ), cathode (4), fuel cell stack heat exchanger (HTX (HeaT eXchange) in FCS) (5), deionized water heat exchanger (HTX for DI (Deionized) water) (7), pump 1 (8) , the pump 2 ( 9 ), the coolant tank ( 10 ), the deionized water tank ( DI water tank) ( 11 ), the coolant heat exchanger ( HTX for coolant) ( 12 ), and the like.

Hydrogen serving as a fuel of the fuel cell is supplied to the anode of the fuel cell stack, and oxygen in the air is supplied to the cathode of the fuel cell stack after passing through an air blower and a humidifier. Electricity is produced by the electrochemical reaction of hydrogen and oxygen supplied to the anode and cathode of the fuel cell stack, and heat and water are discharged as by-products of the reaction. Appropriate cooling control will be performed. DI (deionized) water supplied to the fuel cell stack heat exchanger is supplied from the deionized water tank through the pump 1, and the absorbed heat is transferred to the cooling water through the deionized water heat exchanger. Cooling water is supplied from the cooling water tank to the deionized water heat exchanger through the pump 2, and the absorbed heat is discharged to the outside through the cooling water heat exchanger.

In this case, if the amount of cooling is insufficient or excessive, dry out or flooding may occur in the fuel cell stack, which may reduce or stop power generation in the fuel cell stack.

The appropriate amount of cooling required for cooling the fuel cell stack is closely related to the amount of hydrogen supplied and the amount of electricity generated. In addition, the ratio of water (H2O) to liquid state (water vapor condensation rate ratio, y) among the byproducts of the electrochemical reaction of hydrogen and oxygen produced in the fuel cell stack is a very important variable in determining the amount of cooling. Dry out or flooding of the fuel cell stack can be avoided if it can be found or estimated.

While the inventors of the present invention were studying the thermoeconomic method to accurately find out or estimate the water vapor condensation rate ratio y, the minimum and maximum cooling amount required in the fuel cell stack was determined by the amount of hydrogen supplied, the amount of electricity generated, and the high calorific value of hydrogen ( HHV) and lower calorific value (LHV).

Prevents dry out or flooding of the fuel cell stack by calculating the minimum and maximum cooling amount required for the fuel cell stack from the amount of hydrogen currently supplied and the amount of electricity produced and controlling the cooling device within the corresponding range be able to do

)는 전기 화학적 반응 동안 연료전지 스택(FCS)에서 생성된 총 수증기 중 액체 물의 몰(mol) 분율 즉 수증기 응축률비(y)에 따라 달라지며 이는 다음 수학식과 같이 쓸 수 있다.Input chemical exergy of fuel per unit kmole in fuel cell stack (FCS) (

) depends on the molar fraction of liquid water in the total water vapor generated in the fuel cell stack (FCS) during the electrochemical reaction, that is, the water vapor condensation rate ratio (y), which can be written as the following equation.

는 주어진 온도에서 H₂O의 잠열이다.where LHV is the lower calorific value of hydrogen and HHV is the higher calorific value of hydrogen.

is the latent heat of _{H 2} O at a given temperature.

)은 다음과 같이 구할 수 있다.Molar flow rate of hydrogen fuel consumed in fuel cell stack (FCS) (

) can be obtained as

where I is the current, N _cell is the number of cells in the stack, and F is the Faraday constant, which is about 26801.48 Ah/kmol.

If there is chemical exergy (P therm ) that is not converted into electric power in the fuel cell stack, the exergy _{balance of the} fuel cell system can be written as follows.

는 연료전지 시스템의 수소 연료에 의한 화학적 엑서지이고,

는 연료전지 스택에서 생산되는 전력에 대응되는 엑서지이다. 여기서 연료전지 스택에서 전력으로 변환되지 않은 화학적 엑서지

은 연료전지 스택에서 응축수의 몰분율에 의존한다.

is the chemical exergy by hydrogen fuel of the fuel cell system,

is an exergy corresponding to power generated by the fuel cell stack. Here, chemical exergy that is not converted into electrical power in the fuel cell stack

depends on the mole fraction of condensate in the fuel cell stack.

More specifically, the minimum cooling amount and the maximum cooling amount are

can be calculated by

는 연료전지 스택에 필요한 최소냉각량이고 이보다 냉각량이 적을 경우 과소 냉각되어 연료전지 스택을 고온으로 만들고 최종적으로 드라이 아웃(Dry out)되어 연료전지가 정지되는 상태에 이를 수 있다.

는 연료전지 스택에 필요한 최대냉각량이고 이보다 냉각량이 클 경우 과다 냉각되어 연료전지 스택을 플러딩(Flooding) 상태로 만들어 연료전지 시스템이 매우 비효율적인 운전상태로 될 수 있다.here,

is the minimum amount of cooling required for the fuel cell stack, and if the amount of cooling is less than this, it is undercooled to make the fuel cell stack to a high temperature, and finally dry out, leading to a state in which the fuel cell is stopped.

is the maximum amount of cooling required for the fuel cell stack, and if the amount of cooling is greater than this, overcooling may cause the fuel cell stack to flood, resulting in a very inefficient operation of the fuel cell system.

는 연료전지 스택에서 소비되는 수소의 몰 유량(Mole Flow Rate)이고,

는 연료전지 스택에서 생산되는 전력에 대응되는 엑서지이다. LHV는 수소의 저위발열량(Lower Heating Value)이고, HHV는 수소의 고위발열량(Higher Heating Value이다.

is the molar flow rate of hydrogen consumed in the fuel cell stack,

is an exergy corresponding to power generated by the fuel cell stack. LHV is the lower heating value of hydrogen, and HHV is the higher heating value of hydrogen.

When the minimum cooling amount and the maximum cooling amount are determined, the cooling amount of the fuel cell stack is controlled so that the appropriate cooling amount is greater than or equal to the minimum cooling amount and less than the maximum cooling amount. The amount of cooling of the fuel cell stack may be controlled by controlling the temperature and flow rate of the coolant supplied to the fuel cell stack. If necessary, the pressure of the coolant can also be a control variable.

The total amount of heat generated when fuel is burned is called high calorific value. The calorific value is measured by a calorimeter, and since the temperature of the calorimeter is lowered to 100℃ or less after combustion, water vapor in the combustion gas condenses to become water, and latent heat is released in this process. is the high calorific value. The low calorific value refers to the high calorific value minus the latent heat of water vapor contained in the combustion gas. The actual calorific value of fuel is calculated based on the lower calorific value because, in the case of solid or liquid fuel, moisture contained in the fuel must be evaporated to vaporize and burn the fuel.

Accordingly, the cooling control method of the fuel cell system including the fuel cell stack according to the present invention will be described with reference to FIG. 1 ,

A first step of calculating a minimum amount of cooling required for cooling the fuel cell stack from the flow rate of hydrogen fuel consumed in the fuel cell stack, the low-level calorific value (LHV) of the hydrogen, and the electric power produced in the fuel cell stack; a second step of calculating a maximum amount of cooling required for cooling the fuel cell stack from a flow rate of hydrogen fuel consumed in the fuel cell stack, a high calorific value (HHV) of hydrogen, and electric power generated in the fuel cell stack; a third step of controlling the cooling amount of the fuel cell stack so that the cooling amount of the fuel cell stack is within the range of the minimum cooling amount and the maximum cooling amount.

Here, the minimum cooling amount is

can be calculated by

The maximum cooling amount is

는 연료전지 스택에서 소비되는 수소의 몰 유량(Mole Flow Rate)이고, LHV는 수소의 저위발열량(Lower Heating Value)이고,

는 연료전지 스택에서 생산되는 전력에 대응되는 엑서지이다.)can be calculated by (

is the molar flow rate of hydrogen consumed in the fuel cell stack, LHV is the lower heating value of hydrogen,

is the exergy corresponding to the power generated by the fuel cell stack.)

는 연료전지 스택에서 전기화학적 반응에 의하여 생성된 H₂O가 모두 물이 되는 화학적 엑서지 속도(the rate of chemical exergy)를 나타내며, 최소냉각량

은 연료전지 스택에서 전기화학적 반응에 의하여 생성된 H₂O가 모두 수증기가 되는 화학적 엑서지 속도(the rate of chemical exergy)를 나타낸다.maximum cooling

represents the rate of chemical exergy in which all _{H 2} O generated by the electrochemical reaction in the fuel cell stack becomes water, and the minimum cooling amount

denotes the rate of chemical exergy at which all _{H 2} O generated by the electrochemical reaction in the fuel cell stack becomes water vapor.

은 연소과정에서 발생하는 수증기가 전부 물이 되지 않도록 하여 플러딩을 방지하기 위한 냉각량을 의미한다. 마찬가지로 수소연료의 저위발열량과 관련하여 연산한 최소냉각량

은 연소과정에서 발생하는 물이 전부 수증기 되지 않도록 하여 드라이 아웃을 방지하기 위한 냉각량을 의미한다.In other words, the maximum cooling amount calculated in relation to the high calorific value of hydrogen fuel.

is the amount of cooling to prevent flooding by preventing all water vapor generated in the combustion process from becoming water. Similarly, the minimum cooling amount calculated in relation to the low calorific value of hydrogen fuel.

indicates the amount of cooling to prevent dry-out by preventing all water generated in the combustion process from becoming steam.

_{On the other hand, if chemical exergy (P therm} ) that is not converted into electric power in the fuel cell stack (FCS) is used, the water vapor condensation rate ratio (y) can be calculated (estimated).

The water vapor condensation rate ratio (y) in the fuel cell system can also be obtained by a thermoeconomic method called Modified Productive Structure Analysis (MOPSA).

In the first step, an exergy balance equation and an exergy cost balance equation of the fuel cell system are generated, but in the exergy balance equation and the exergy cost balance equation, the water vapor condensation rate ratio (y ), an exergy balance equation and an exergy cost balance equation are generated for each component constituting the fuel cell system. The second step creates a cost balance for the entire fuel cell system. In the third step, the water vapor condensation rate ratio (y) can be calculated by calculating the water vapor condensation rate ratio (y) at which the power generation unit price calculated from the cost balance equation of the entire fuel cell system and the generation unit cost calculated from the cost balance equation of each component are equal. have.

In the fuel cell system of the present invention, each component generating the exergy balance is an air blower, a humidifier, an anode, a cathode, a fuel cell stack heat exchanger (HTX in FCS), Includes fuel cell stack (FCS), deionized water heat exchanger (HTX for DI water), pump 1, pump 2, coolant tank, DI water tank, and HTX for coolant do. Next, an exergy cost balance equation is generated to include the water vapor condensation rate ratio y for each component.

A cost balance equation for the entire fuel cell system may be generated using the exergy cost balance equation of each component.

As a final step, it is possible to calculate the water vapor condensation rate ratio (y) at which the unit cost of power generation calculated from the cost balance equation of the entire fuel cell system is equal to the unit cost of power generation calculated from the cost balance equation of each component.

The water vapor condensation rate ratio (y) calculated by the thermoeconomic method is CLmax And it can be seen that the same result as the water vapor condensation rate ratio (y) calculated by CLmin is shown.

The following Table 1 is a table showing the results according to various operating conditions of the fuel cell system according to an embodiment of the present invention. The unit cost of electricity calculated by MOPSA under 100% load condition and 50% load condition for 1KW PEMFC system (Unit Cost of Electricity, $/GJ), PEMFC System Efficiency, Calculated Mole ftaction of Liquid Water by MOPSA Method, Water Vapor Condensation Rate Ratio (y), Measured Mass Flow Rate of Liquid Water (measured mass flow rate of liquid water, kg/h), cooling rate in FXS, kJ/h /h) and the maximum cooling rate (Maximun Cooling rate, CLmax, kJ/h) is shown.

[Table 1]

At 100% load, the unit cost of electricity is about 247 $/GJ, but at 50% load it increases to 435 $/GJ. This difference in unit cost is because the initial investment cost for constructing the PEMFC system is high. On the other hand, it can be seen that the efficiency of the PEMFC system is about 39% and 41% under 50% and 100% load conditions, and there is no significant difference.

In [Table 1], in cases 1 to 5, the unit cost of electricity can be calculated using MOPSA because the cooling amount of the FCS is in the range between the minimum cooling amount CLmin and the maximum cooling amount CLmax. If the cooling rate of FCS is the same as Cases 6 and 7, where the minimum cooling rate and the maximum cooling rate are the same, the unit cost of electricity cannot be calculated using MOPSA, and in cases 6 and 7 of [Table 1], the unit cost of electricity is calculated by another method (Moran's Method).

Cases 6 and 7 show the case where the cooling amount of the FCS is larger than the maximum required cooling amount. This case may occur when the air blower 1 that supplies air to the FCS does not supply enough air to cope with the current load to be produced by the reaction with hydrogen in the FCS due to a cause such as deterioration in performance.

Due to excessive cooling, a cell temperature may decrease, and as a result, flooding may occur in a gas diffusion layer (GDL) and a cathode channel.

On the other hand, there may be a case where the amount of cooling of the FCS is smaller than the minimum amount of cooling required for the FCS. This situation may occur when the DI water (deionized water) pump (pump 1) does not provide a sufficient flow rate, in which case the cell temperature increases and as a result, dry out of the FCS membrane may occur. .

Meanwhile, according to FIG. 2 , the cooling control device 120 of the fuel cell system according to an exemplary embodiment of the present invention provides a flow rate of hydrogen fuel consumed in a fuel cell stack, a low-level calorific value (LHV) of hydrogen, and production in the fuel cell stack. The minimum cooling amount calculating unit 121 that calculates the minimum amount of cooling of the fuel cell stack from the generated electric power; and the flow rate of hydrogen fuel consumed in the fuel cell stack, the high calorific value (HHV) of hydrogen, and power produced in the fuel cell stack a maximum cooling amount calculating unit 122 for calculating the maximum cooling amount of the fuel cell stack from The cooling amount control unit 123; may include. The cooling amount controller may control the cooling amount of the fuel cell stack by controlling the temperature and flow rate of the coolant supplied to the fuel cell stack. Since the cooling control apparatus 120 for a fuel cell system according to an exemplary embodiment of the present invention is different from the above-described cooling control method for a fuel cell system only in the category of the invention, substantially the same description will not be repeated.

In the above, the cooling control method of the fuel cell system and the apparatus have been described with reference to the embodiment, but it is obvious that those skilled in the art will understand that it can be applied to cooling control of other systems. In addition, it will be understood by those skilled in the art that various modifications and changes can be made to the present invention without departing from the spirit and scope of the present invention as set forth in the following claims.

1: Air Blower
2: Humidifier
3: Anode)
4: cathode
5: Fuel cell stack heat exchanger (HTX (HeaT eXchange) in FCS)
6: Fuel cell stack (FCS, Fuel Cell Stack)
7: Deionized water heat exchanger (HTX for DI (Deionized) water)
8 : Pump 1 (Pump1)
9: Pump 2 (Pump2)
10: Coolant Water Tank
11: Deionized water tank (DI (Deionized) water tank)
12: HTX for coolant
120: cooling control device
121: Minimum cooling amount calculation unit
122: maximum cooling amount calculation unit
123: cooling amount control unit

Claims (6)

A method for controlling cooling of a fuel cell system including a fuel cell stack, the method comprising:
A first step of calculating a minimum amount of cooling required for cooling the fuel cell stack from the flow rate of hydrogen fuel consumed in the fuel cell stack, the low-level calorific value (LHV) of hydrogen, and the electric power produced in the fuel cell stack;
a second step of calculating a maximum amount of cooling required for cooling the fuel cell stack from a flow rate of hydrogen fuel consumed in the fuel cell stack, a high calorific value (HHV) of hydrogen, and electric power generated in the fuel cell stack;
and a third step of controlling the cooling amount of the fuel cell stack so that the cooling amount of the fuel cell stack is within the range of the minimum cooling amount and the maximum cooling amount.
The method according to claim 1,
In the first step, the minimum amount of cooling is

Cooling control method of a fuel cell system, characterized in that calculated by
(here,

is the minimum amount of cooling,

is the molar flow rate of hydrogen consumed in the fuel cell stack, LHV is the lower heating value of hydrogen,

is the exergy corresponding to the power generated by the fuel cell stack.)
The method according to claim 1,
In the second step, the maximum amount of cooling is

Cooling control method of a fuel cell system, characterized in that calculated by
(here,

is the maximum cooling amount,

is the molar flow rate of hydrogen consumed in the fuel cell stack, HHV is the higher heating value of hydrogen,

is the exergy corresponding to the power generated by the fuel cell stack.)
The method according to claim 1,
The cooling control method of the fuel cell system, characterized in that the cooling of the fuel cell stack in the third step is to control the amount of cooling by controlling the temperature and flow rate of the coolant supplied to the fuel cell stack.
In the cooling control apparatus of a fuel cell system including a fuel cell stack,
A minimum cooling amount calculating unit for calculating a minimum amount of cooling of the fuel cell stack from the flow rate of hydrogen fuel consumed in the fuel cell stack, the low-level calorific value (LHV) of hydrogen, and the electric power produced in the fuel cell stack; And
A maximum cooling amount calculating unit that calculates the maximum amount of cooling of the fuel cell stack from the flow rate of hydrogen fuel consumed in the fuel cell stack, the high calorific value (HHV) of hydrogen, and the electric power produced in the fuel cell stack; and
and a cooling amount control unit controlling the amount of cooling of the fuel cell stack so that the amount of cooling of the fuel cell stack is within the range of the minimum cooling amount and the maximum cooling amount.
6. The method of claim 5,
wherein the cooling amount controller controls the cooling amount of the fuel cell stack by controlling the temperature and flow rate of the coolant supplied to the fuel cell stack.

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