CN116072929A - Comprehensive control method of fuel cell cogeneration system - Google Patents

Abstract

The invention relates to the technical field of fuel cells, in particular to a comprehensive control method of a fuel cell cogeneration system. The control strategy of the fuel cell cogeneration system aims to solve the problem of poor flexibility. For this purpose, the integrated control method of the present application includes: acquiring the actual thermoelectric ratio of the fuel cell unit; acquiring a required thermoelectric ratio between required heat and required electric quantity within a period of time; comparing the magnitude of the required thermoelectric ratio with the actual thermoelectric ratio; and controlling the fuel cell cogeneration system to operate in a thermal following mode or an electric following mode based on the comparison result. The comprehensive control method can flexibly match the electric heating requirement of a user when in application, improves the application range of products, reduces energy waste and realizes the maximization of the efficiency of the fuel cell cogeneration system.

Description

Comprehensive control method of fuel cell cogeneration system

Technical Field

The invention relates to the technical field of fuel cells, in particular to a comprehensive control method of a fuel cell cogeneration system.

Background

The fuel cell cogeneration system is slowly accepted by the vast users due to the characteristics of high thermal efficiency, small environmental pollution and the like. Currently, fuel cell cogeneration systems mainly have three control strategies of electric following, thermal following and base load following when applied.

The electric following strategy mainly adjusts the output power of the fuel cell according to the electricity consumption requirement of a user, the thermal following strategy mainly adjusts the output power of the fuel cell according to the heat consumption requirement of the user, and the basic load following strategy is based on the two. But for users, the electricity and heat demands are not strictly performed according to a certain control strategy, but vary with different seasons, times or different life plans. The three control strategies have the defects that the application scenes are limited and the diversified electricity and heat requirements of users cannot be met.

Accordingly, there is a need in the art for a new integrated control method for a fuel cell cogeneration system that addresses the above-described problems.

Disclosure of Invention

In order to solve at least one of the above problems in the prior art, that is, in order to solve the problem of poor flexibility in the control strategy of the fuel cell cogeneration system, the present application provides a comprehensive control method of the fuel cell cogeneration system, which includes a fuel cell unit, a heat storage unit, an auxiliary heat unit, a heat dissipation cooling unit, a power storage unit, an auxiliary power unit, and a grid-connected unit,

The fuel cell unit can transfer heat to the heat storage unit, the auxiliary heat unit is used for heating water of the heat storage unit, the heat dissipation cooling unit is used for cooling the fuel cell unit, the fuel cell unit can store the generated electricity to the electricity storage unit or access the electricity grid through the grid-connected unit, the auxiliary electricity unit is used for introducing electricity of the electricity grid,

the comprehensive control method comprises the following steps:

acquiring an actual thermoelectric ratio of the fuel cell unit;

acquiring a required thermoelectric ratio between required heat and required electric quantity within a period of time;

comparing the magnitude of the desired thermoelectric ratio to the actual thermoelectric ratio;

and controlling the fuel cell cogeneration system to operate in a thermal following mode or an electric following mode based on the comparison result.

In the above-mentioned preferred technical solution of the integrated control method of a fuel cell cogeneration system, the step of controlling the fuel cell cogeneration system to operate in a heat following mode or an electricity following mode based on the comparison result further includes:

controlling the fuel cell cogeneration system to operate in the heat following mode if the required thermoelectric ratio is greater than the actual thermoelectric ratio;

And if the required thermoelectric ratio is smaller than or equal to the actual thermoelectric ratio, controlling the fuel cell cogeneration system to operate in the electric following mode.

In a preferred embodiment of the above integrated control method for a fuel cell cogeneration system, the step of controlling the fuel cell cogeneration system to operate in the heat following mode further includes:

controlling an operating state of the fuel cell unit based on the required heat in the required heat-to-electricity ratio;

acquiring the actual power generation amount of the fuel cell unit;

judging the actual power generation amount and the required power;

and controlling the running states of the power storage unit, the auxiliary power unit and the grid-connected unit based on the comparison result.

In a preferred embodiment of the above integrated control method for a fuel cell cogeneration system, the step of controlling the operation state of the fuel cell unit based on the required heat in the required heat-to-electricity ratio further includes:

comparing the required heat with the maximum output heat of the fuel cell unit;

controlling the fuel cell unit to operate together with the auxiliary heat unit to match the required heat when the required heat is greater than the maximum output heat;

When the required heat quantity is smaller than or equal to the maximum output heat quantity, further comparing the required heat quantity with the minimum output heat quantity of the fuel cell unit;

when the required heat is greater than or equal to the minimum output heat, controlling the fuel cell unit to independently operate so as to match the required heat;

and when the required heat quantity is smaller than the minimum output heat quantity, controlling the fuel cell unit to stop running, and controlling the auxiliary heat unit to start running so as to match the required heat quantity.

In the preferred technical solution of the above-mentioned integrated control method of a fuel cell cogeneration system, the step of controlling the operation states of the electricity storage unit, the auxiliary electricity unit, and the grid-connected unit based on the comparison result further includes:

when the actual power generation amount is larger than the required power amount, controlling the power storage unit to store power or controlling the grid-connected unit to supply power and grid;

and when the actual power generation quantity is smaller than the required power quantity, controlling the power storage unit to independently supply power or controlling the auxiliary power unit to supply power.

In the preferred technical scheme of the comprehensive control method of the fuel cell cogeneration system, the step of controlling the electricity storage unit to store electricity or controlling the grid-connected unit to supply electricity and grid-connected further comprises:

Acquiring the residual electric quantity of the electricity storage unit;

comparing the residual electric quantity with an electric quantity upper limit threshold value;

if the residual electric quantity is smaller than the electric quantity upper limit threshold value, controlling the electric storage unit to store electricity;

if the residual electric quantity is larger than or equal to the electric quantity upper limit threshold value, controlling the grid-connected unit to supply power and realize grid connection; and/or

The step of "controlling the power supply of the power storage unit alone or controlling the power supply of the auxiliary power unit" further includes:

acquiring the residual electric quantity of the electricity storage unit;

comparing the residual electric quantity with an electric quantity lower limit threshold value;

if the residual electric quantity is larger than the electric quantity lower limit threshold value, controlling the electricity storage unit to supply power;

and if the residual electric quantity is smaller than or equal to the electric quantity lower limit threshold value, controlling the auxiliary electric unit to supply power.

In a preferred embodiment of the above integrated control method for a fuel cell cogeneration system, the step of controlling the fuel cell cogeneration system to operate in the electric following mode further includes:

controlling an operating state of the fuel cell unit based on the required electrical quantity in the required thermoelectric ratio;

acquiring the actual heat generation amount of the fuel cell unit;

Comparing the actual heat generation amount with the required heat;

and controlling the operation states of the heat storage unit, the auxiliary heat unit and the heat dissipation cooling unit based on the comparison result.

In a preferred embodiment of the above integrated control method for a fuel cell cogeneration system, the step of controlling the operation state of the fuel cell unit based on the required electric power in the required thermoelectric ratio further includes:

comparing the required electric quantity with the maximum output electric quantity of the fuel cell unit;

when the required electric quantity is larger than the maximum output electric quantity, controlling the fuel cell unit and the auxiliary electric unit to operate together so as to match the required electric quantity;

when the required electric quantity is smaller than or equal to the maximum output electric quantity, further comparing the required electric quantity with the minimum output electric quantity of the fuel cell unit;

when the required electric quantity is greater than or equal to the minimum output electric quantity, controlling the fuel cell unit to independently operate so as to match the required electric quantity;

and when the required electric quantity is smaller than the minimum output electric quantity, controlling the fuel cell unit to stop running, and controlling the auxiliary electric unit to start running so as to match the required electric quantity.

In the preferred technical solution of the above-mentioned integrated control method of a fuel cell cogeneration system, the step of controlling the operation states of the heat storage unit, the auxiliary heat unit, and the heat dissipation cooling unit based on the comparison result further includes:

when the actual heat generation amount is larger than the required heat amount, controlling the heat storage unit to store heat or controlling the heat dissipation cooling unit to start running;

and when the actual heat generation amount is smaller than the required heat amount, controlling the auxiliary heat unit to start heating.

In the preferred technical solution of the above-mentioned integrated control method of a fuel cell cogeneration system, the step of "controlling the heat storage unit to store heat or controlling the heat dissipation cooling unit to start running" further includes:

acquiring the actual temperature of the heat storage unit;

comparing the actual temperature with a set temperature;

if the actual temperature is greater than or equal to the set temperature, controlling the heat dissipation cooling unit to start running;

and if the actual temperature is smaller than the set temperature, controlling the heat storage unit to store heat.

In the preferred technical scheme of the application, the heat and electricity ratio of the requirements of the user side is compared with the actual heat and electricity ratio of the fuel cell unit, and the heat following mode or the electricity following mode of the fuel cell cogeneration system is selectively controlled based on the comparison result.

Further, in the heat following mode, the running state of the fuel cell unit is controlled according to the required heat based on the required heat in the required heat-electricity ratio, so that the heat generated by the fuel cell unit preferentially meets the required heat of a user, and then the running states of the power storage unit, the auxiliary power unit and the grid-connected unit are controlled based on the actual power generation amount and the required power of the fuel cell unit.

Further, when the required heat is larger than the maximum output heat, the fuel cell unit and the auxiliary heat unit are controlled to operate together, so that the heat consumption requirement of a user can be ensured, and meanwhile, the system is ensured to operate in a high-efficiency zone.

Further, by controlling the fuel cell unit to stop operation and controlling the auxiliary heat unit to start operation when the required heat is smaller than the minimum output heat, it is possible to avoid the life of the fuel cell unit excessively lost due to the fuel cell unit operating at a lower power while ensuring the user's heat demand.

Further, when the actual power generation quantity is larger than the required power quantity and the residual power quantity of the power storage unit is smaller than the power quantity upper limit threshold value, the power storage unit is controlled to store power, and the heat following control method can reasonably utilize the redundant power quantity to store, so that the overall efficiency of the system is improved. When the actual power generation quantity is larger than the required power quantity and the residual power quantity of the power storage unit is larger than or equal to the upper limit threshold value of the power quantity, the grid-connected unit is controlled to supply power for grid connection. When the actual power generation quantity is smaller than the required power quantity and the residual power quantity of the power storage unit is larger than the lower limit threshold of the power quantity, the power storage unit is controlled to supply power, the power demand of a user can be met, and meanwhile the power quantity in the power storage unit is utilized to make up for the shortage of the power supply quantity. When the actual power generation quantity is smaller than the required power quantity and the residual power quantity of the power storage unit is smaller than or equal to the lower limit threshold value of the power quantity, the auxiliary power unit is controlled to supply power, the power requirement of a user can be met, and meanwhile, the power quantity in the auxiliary power unit is utilized to make up for the shortage of the power supply quantity.

Further, in the electricity following mode, the running state of the fuel cell unit is controlled according to the required electric quantity in the required heat-electricity ratio, so that the electricity generation of the fuel cell unit preferentially meets the required electric quantity of a user, and then the running states of the heat storage unit and the auxiliary heat unit are controlled based on the actual heat generation quantity and the required heat quantity of the fuel cell unit.

Further, when the required electric quantity is larger than the maximum output electric quantity, the fuel cell unit and the auxiliary electric unit are controlled to operate together, so that the electricity consumption requirement of a user can be ensured, and meanwhile, the system is ensured to operate in a high-efficiency interval.

Further, by controlling the fuel cell unit to stop operating and controlling the auxiliary electric unit to start operating when the required electric quantity is smaller than the minimum output electric quantity, the service life of the fuel cell unit excessively consumed due to the fact that the fuel cell unit operates at lower power can be avoided while the electricity consumption requirement of a user is ensured.

Further, when the actual heat generation amount is larger than the required heat amount and the actual temperature of the heat storage unit is smaller than the set temperature, the heat storage unit is controlled to store heat, and the electric following control method can reasonably utilize redundant heat to store, so that the overall efficiency of the system is improved. Through when the actual heat production quantity is greater than the demand heat and the actual temperature of the heat storage unit is greater than or equal to the set temperature, the heat dissipation cooling unit is controlled to start to operate. Further, when the actual heat generation amount is smaller than the required heat amount, the auxiliary heat unit is controlled to start heating, so that the heat requirement of a user can be met, and meanwhile, the system is ensured to operate in a high-efficiency interval.

Drawings

The integrated control method of the fuel cell cogeneration system of the present application is described below with reference to the drawings. In the accompanying drawings:

FIG. 1 is a system diagram of a fuel cell cogeneration system of the present application;

FIG. 2 is a main flow chart of the integrated control method of the fuel cell cogeneration system of the present application;

FIG. 3 is a logic diagram of controlling the operating state of a fuel cell unit according to the required heat in the integrated control method of the fuel cell cogeneration system of the present application;

fig. 4 is a logic diagram of controlling an operation state of a fuel cell unit according to a required electric quantity in the integrated control method of the fuel cell cogeneration system of the present application.

List of reference numerals

1. A fuel cell unit; 2. a heat storage unit; 3. an auxiliary heating unit; 4. an electricity storage unit; 5. and a heat dissipation cooling unit.

Detailed Description

Preferred embodiments of the present application are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are merely for explaining the technical principles of the present application, and are not intended to limit the scope of the present application. For example, although the following details of the method of the present application are described below, those skilled in the art may combine, split and exchange the following steps without departing from the basic principles of the present application, and the technical solution thus modified does not change the basic concepts of the present application, and therefore falls within the scope of protection of the present application.

Referring first to fig. 1, a brief description will be given of a fuel cell cogeneration system of the present application. Fig. 1 is a system diagram of a fuel cell cogeneration system according to the present application.

As shown in fig. 1, the fuel cell cogeneration system mainly includes a fuel cell unit 1, a heat storage unit 2, an auxiliary heat unit 3, a heat radiation cooling unit 5, a power storage unit 4, an auxiliary power unit, and a grid-connected unit (auxiliary power unit and grid-connected unit are not shown in the drawing). Wherein the fuel cell unit 1 has a fuel inlet, a fuel outlet, an oxidant inlet, an oxidant outlet, a cooling inlet, a cooling outlet, and the like. The fuel inlet and the fuel outlet are in communication with a fuel supply system to effect supply of fuel and discharge of remaining fuel, and the oxidant inlet and the oxidant outlet are in communication with an oxidant supply system to effect supply of oxidant and discharge of reaction products and remaining oxidant. The cooling inlet and the cooling outlet exchange heat with the heat storage unit 2 through the heat exchanger, and the heat storage unit 2 is usually a heat preservation water tank, so that heat in the fuel cell unit 1 can be exchanged through the heat exchanger and transferred to the heat preservation water tank to heat water in the water tank for a user to use. The heat radiation cooling unit 5 may be, for example, a radiator or a cooling water tank, and the cooling water circulates between the fuel cell unit 1 and the radiator or the cooling water tank to cool the inside of the fuel cell unit 1. The auxiliary heating unit 3 is usually an electric heater or a ceramic heater, which is arranged in the heat preservation water tank or on the water outlet pipe of the heat preservation water tank, and when the water temperature in the heat preservation water tank is insufficient to meet the requirement of a user, the auxiliary heating unit 3 is started to heat the water in the heat preservation water tank or heat the water outlet of the heat preservation water tank.

The electricity storage unit 4 is usually a storage battery, the grid-connected unit is usually a grid-connected inverter, and the charges generated by the fuel cell unit 1 can be stored in the electricity storage unit 4 after being converted by a voltage stabilizing, current converting and other conversion circuits, or can be connected into a power grid through the grid-connected unit. The auxiliary electrical unit is connected to the grid, which is able to introduce the power of the grid so that the auxiliary electrical power is provided by the auxiliary electrical unit when the fuel cell unit 1 generates insufficient electrical energy for the user to do so.

The above arrangement of the fuel cell cogeneration system is common knowledge in the art, and will not be described in detail in this application. Of course, the specific composition of the fuel cell cogeneration system described above is not exclusive and can be modified by one skilled in the art without departing from the principles of the present application.

The integrated control method of the present application will be described with reference to fig. 2. Fig. 2 is a main flow chart of the comprehensive control method of the fuel cell cogeneration system of the present application.

As shown in fig. 2, in order to solve the problem of poor flexibility of the control strategy of the fuel cell cogeneration system, the integrated control method of the fuel cell cogeneration system of the present application includes:

S101, acquiring the actual thermoelectric ratio of a fuel cell unit; for example, when the fuel cell unit is operated at the time of the start-up operation, the fuel cell unit is operated at the rated power, and at this time, the fuel cell unit is operated at the optimal thermoelectric ratio, and therefore the actual thermoelectric ratio, that is, the optimal thermoelectric ratio, can be directly obtained as the actual thermoelectric ratio. When the fuel cell units are operated, electricity is generated and heat is generated according to the operation characteristics of the fuel cell units, and the arrangement modes (such as the configuration and the arrangement modes of the proton exchange membranes and the like) of the fuel cell units are different, so that the ratio of electricity generation to heat generation is also different. Therefore, for each fuel cell unit, on the premise of ensuring the optimal service life, a better ratio of heat generation to electricity generation, namely the optimal thermoelectric ratio exists.

Of course, the actual thermoelectric ratio may also be obtained by other manners, such as obtaining the current power generation amount and the current heat generation amount of the fuel cell unit, and calculating the ratio of the current heat generation amount to the current power generation amount, that is, the actual thermoelectric ratio. For example, for the current electricity generation amount, the current electricity generation amount in the past period (such as 1 min) can be calculated by setting a power sensor, a power calculation module and the like on the fuel cell unit to collect and calculate the electric power of the fuel cell unit. For another example, the current heat generation amount may be obtained by setting temperature sensors in the fuel cell unit to respectively collect the temperatures of the cooling inlet and the cooling outlet, and then calculating to obtain the current heat generation amount of the fuel cell unit for a period of time (for example, 1 min). For another example, when the fuel cell unit is operated at the optimal thermoelectric ratio, the current heat generation amount may be calculated by the current heat generation amount of the fuel cell and the optimal thermoelectric ratio, or the current heat generation amount may be calculated by the current heat generation amount of the fuel cell and the optimal thermoelectric ratio.

S103, acquiring a required thermoelectric ratio between required heat and required electric quantity in a period of time; for example, for the required heat, the required heat (J) can be calculated by providing a temperature sensor and a flow sensor at the outlet of the heat storage unit, for example, by acquiring the water flow and the water temperature of the heat storage unit in the past 1min, and calculating the required heat (J) by a heat formula. For the required electric quantity, a power sensor, a power calculation module and the like can be arranged to collect and calculate the electric power of the user side, so as to calculate the required electric quantity of the user in the past period of time, for example, calculate the required electric quantity (kWh) of the user side in the past 1min period of time. After the required heat and the required electric quantity are obtained, the required thermoelectric ratio is obtained by calculating the ratio of the required heat and the required electric quantity. When the required thermoelectric ratio is calculated, heat (J) can be converted into electric quantity (kWh) for calculation, and the electric quantity (kWh) can also be converted into heat (J) for calculation.

S105, comparing the required thermoelectric ratio with the actual thermoelectric ratio; for example, the magnitude of the difference or ratio is calculated.

S107, controlling the fuel cell cogeneration system to operate in a heat following mode or an electric following mode based on the comparison result; for example, in a preferred embodiment, when the required thermoelectric ratio is greater than the actual thermoelectric ratio, it is proved that the user's heat demand is greater than the electricity demand, and then the user selects to operate in the heat following mode of heat metering; in contrast, if the required thermoelectric ratio is less than or equal to the actual thermoelectric ratio, it is proved that the electricity demand of the user is greater than the heat demand, and at this time, the operation in the electric following mode of electric fixed heat is selected.

By comparing the required thermoelectric ratio of the user side with the actual thermoelectric ratio of the fuel cell unit and selectively controlling the operation heat following mode or the electricity following mode of the fuel cell cogeneration system based on the comparison result, the comprehensive control method can flexibly match the electric heating requirement of the user when in application, improves the application range of the product, reduces the energy waste and realizes the maximization of the efficiency of the fuel cell cogeneration system.

The following is a description of a specific control manner of the thermal following mode of the present application.

In one embodiment, the step of "controlling the fuel cell cogeneration system to operate in the heat following mode" further comprises: controlling an operating state of the fuel cell unit based on the required heat in the required heat to power ratio; acquiring the actual power generation amount of the fuel cell unit; judging the actual power generation amount and the required power; and controlling the running states of the power storage unit, the auxiliary power unit and the grid-connected unit based on the comparison result.

Specifically, after entering the heat following mode, the fuel cell unit is controlled to operate with the required heat in the required heat-to-electricity ratio as a control target so that the heat generation amount of the fuel cell unit is equal to or infinitely close to the required heat.

For example, referring to fig. 3, fig. 3 is a logic diagram of controlling an operation state of a fuel cell unit according to a required heat in the integrated control method of the fuel cell cogeneration system of the present application.

As shown in fig. 3, in one possible embodiment, the step of "controlling the operation state of the fuel cell unit based on the required heat in the required heat-to-electricity ratio" further includes:

s201, comparing the required heat with the maximum output heat of the fuel cell unit; when the required heat is greater than the maximum output heat, step S203 is executed, otherwise, when the required heat is less than or equal to the maximum output heat, step S205 is executed.

S203, controlling the fuel cell unit and the auxiliary heat unit to operate together so as to match the required heat.

S205, further comparing the required heat with the minimum output heat of the fuel cell unit; when the required heat is equal to or greater than the minimum output heat, step S207 is performed; otherwise, when the required heat is smaller than the minimum output heat, step S209 is performed.

S207, controlling the fuel cell units to independently operate so as to match the required heat.

S209, controlling the fuel cell unit to stop running and controlling the auxiliary heat unit to start running so as to match the required heat.

The maximum output heat is the heat generated by the fuel cell unit when operating at the maximum output power, and the maximum output power can be obtained based on experiments or experience. When the required heat is larger than the maximum output heat, the fuel cell unit is proved to be operated at the maximum output power and cannot meet the heat requirement of a user, and the fuel cell unit and the auxiliary heat unit are controlled to operate together at the moment so as to meet the heat required by the user, and meanwhile, the system is ensured to operate in a high-efficiency interval.

When the fuel cell unit is operated with lower output power, the loss is easy to be caused to the operation life of the fuel cell unit, so that when the required heat quantity is smaller than or equal to the maximum output heat quantity, the required heat quantity and the minimum output heat quantity are further judged. The minimum output heat, i.e., the heat generated by the fuel cell unit operating at the minimum output power, may be obtained based on experimentation or experience. When the required heat is greater than or equal to the minimum output heat, the fuel cell unit is proved to operate in a better power interval, and the heat requirement of a user can be met by independently operating the fuel cell unit, and the fuel cell unit is controlled to independently operate at the moment so as to meet the heat required by the user. When the required heat is smaller than the minimum output heat, the fact that the required heat of a user is lower is proved, the fuel cell unit operates at lower output power, the service life of the fuel cell unit is damaged, the fuel cell unit is controlled to stop operating, the auxiliary heat unit is controlled to start operating, the service life of the fuel cell unit is protected, and meanwhile the required heat of the user is met through the auxiliary heat unit.

Of course, the above-mentioned development mode of the step of controlling the operation state of the fuel cell unit based on the required heat in the required heat-electricity ratio is only a preferred embodiment, and those skilled in the art can adjust the above-mentioned mode without departing from the principles of the present application, so that the present application can be applied to more specific application scenarios. For example, when the required heat amount is smaller than the maximum output heat amount, no further judgment may be made, and the operation of the fuel cell unit may be controlled directly based on the required heat amount.

After the actual heat generation amount of the fuel cell unit is controlled to be matched with the required heat amount, whether the actual power generation amount of the fuel cell unit is consistent with the required power amount at the moment can be further judged, and then the running states of the power storage unit, the auxiliary power unit and the grid-connected unit are controlled according to the judging result.

Specifically, when the fuel cell unit is operated at the optimal thermoelectric ratio, the actual amount of electricity generated may be calculated by the actual amount of electricity generated by the fuel cell and the optimal thermoelectric ratio, wherein the manner of obtaining the actual amount of electricity generated may be referred to the current amount of electricity generated as described above. Of course, the actual power generation amount may also be obtained by referring to the above-described current power generation amount obtaining manner.

After the actual electricity generation amount is obtained, the actual electricity generation amount is compared with the required electricity generation amount, for example, the actual electricity generation amount is compared with the required electricity generation amount in a mode of calculating a difference value or a ratio. And then controlling the running states of the power storage unit, the auxiliary power unit and the grid-connected unit based on the comparison result.

Specifically, in one possible embodiment, the step of "controlling the operation states of the power storage unit, the auxiliary power unit, and the grid-connected unit based on the comparison result" further includes:

(1) When the actual power generation amount is larger than the required power amount, the power storage unit is controlled to store power or the grid-connected unit is controlled to supply power and grid.

When the actual power generation amount is larger than the required power generation amount, the power generated by the fuel cell unit is proved to be larger than the power required by a user, and at the moment, redundant power can be stored preferentially, and residual energy treatment is carried out after the power is fully stored. For example, the redundant electric quantity can be stored in the electric storage unit, or can be supplied and connected through the grid connection unit after the electric quantity is full, and the electric quantity is fed back to the power grid.

In one possible embodiment, the excess electrical energy may be processed as follows: obtaining the residual electric quantity of the electricity storage unit; comparing the residual electric quantity with an electric quantity upper limit threshold value; if the residual electric quantity is smaller than the electric quantity upper limit threshold value, controlling the electric storage unit to store electricity; and if the residual electric quantity is larger than or equal to the electric quantity upper limit threshold value, controlling the grid-connected unit to supply power and connect.

When the actual power generation amount is larger than the required power amount, the residual power amount of the power storage unit is firstly obtained, and then the residual power amount is compared with the power amount upper limit threshold value to judge whether the current power storage unit is sufficient in power amount. The upper limit of the electric quantity threshold can be the maximum electric quantity of the electric storage unit, or can be an electric quantity value near the maximum electric quantity, such as 85-95% of the maximum electric quantity. If the residual electric quantity is smaller than the electric quantity upper limit threshold value, the current electric quantity of the electric storage unit is proved to be insufficient, the electric quantity is required to be supplemented, at the moment, the electric storage unit is controlled to store electricity, and the redundant electric quantity of the electric quantity generated by the fuel cell unit after the electric quantity required by a user is removed is supplemented to the electric storage unit; and if the residual electric quantity is larger than or equal to the electric quantity upper limit threshold value, proving that the electric quantity of the current electricity storage unit is sufficient, and supplementing is not needed, and controlling the grid-connected unit to supply power and connect to the grid at the moment so as to feed back the redundant electric quantity to the power grid.

(2) When the actual power generation quantity is smaller than the required power quantity, the power storage unit is controlled to supply power independently or the auxiliary power unit is controlled to supply power.

When the actual electricity generation quantity is smaller than the required electricity quantity, the electric energy generated by the fuel cell unit is proved to be insufficient to meet the requirements of users, and at the moment, the part with insufficient electric energy is supplemented through the electricity storage unit or the auxiliary electricity unit.

In one possible embodiment, the insufficient amount of electricity may be replenished by: obtaining the residual electric quantity of the electricity storage unit; comparing the residual electric quantity with an electric quantity lower limit threshold value; if the residual electric quantity is larger than the electric quantity lower limit threshold value, controlling the electricity storage unit to supply power; and if the residual electric quantity is smaller than or equal to the electric quantity lower limit threshold value, controlling the auxiliary electric unit to supply power.

When the actual power generation amount is smaller than the required power amount, the residual power amount of the power storage unit is firstly obtained, and then the residual power amount is compared with the power amount lower limit threshold value to judge whether the current power storage unit has residual power or not. The lower limit threshold of the electric quantity can be the electric quantity of the electricity storage unit when no electricity exists, and can also be other lower electric quantity values, such as 5-10% of the maximum electric quantity. If the residual electric quantity is smaller than or equal to the electric quantity lower limit threshold value, the fact that the electric quantity of the current electric storage unit is insufficient is proved, the electric supplement can not be carried out through the electric storage unit, at the moment, the auxiliary electric unit is controlled to supply power, and the electric energy of the power grid is used for meeting the requirements of users; and if the residual electric quantity is larger than the electric quantity lower limit threshold value, proving that the electric quantity of the current electric storage unit is sufficient, controlling the electric storage unit to supply power at the moment, and utilizing the electric quantity in the electric storage unit to make up for the deficiency of the actual electric quantity.

(3) And when the actual power generation quantity is equal to the required power quantity, controlling the fuel cell cogeneration system to keep the current running state.

When the actual electricity generation amount is equal to the required electricity amount, the current whole fuel cell cogeneration system is proved to be in a more ideal running state, namely the electricity generation and the heat generation are basically equal to the current requirements of users, and the system runs in a relatively balanced state at the moment, so that no adjustment is needed.

It should be noted that, in the present application, the "actual electricity generation amount is equal to the required electricity amount" is not strictly static, but is a dynamic one, in other words, as long as the electricity generation amount of the fuel cell unit is approximately equal to the required electricity consumption amount, the two are considered to be equal, that is, the electricity generation amount and the electricity consumption amount are allowed to float within a certain small deviation.

Of course, the above-mentioned deployment method is only a preferred embodiment, and those skilled in the art can adjust the above-mentioned method without departing from the principles of the present application, so that the present application can be adapted to more specific application scenarios. For example, when the actual power generation amount is smaller than the required power generation amount, the auxiliary power unit can be directly controlled to supply power; or when the actual power generation amount is larger than the required power amount, directly controlling the grid-connected unit to supply power and realize grid connection.

The following is a description of a specific control manner of the thermal following mode of the present application.

In one embodiment, the step of "controlling the fuel cell cogeneration system to operate in the heat following mode" further comprises: controlling an operating state of the fuel cell unit based on the required electric quantity in the required thermoelectric ratio; acquiring the actual heat generation amount of the fuel cell unit; comparing the actual heat generation amount with the required heat; and controlling the operation states of the heat storage unit, the auxiliary heat unit and the heat dissipation cooling unit based on the comparison result.

Specifically, after the electric following mode is entered, the fuel cell unit is controlled to operate by taking the required electric quantity in the required thermoelectric ratio as a control target, so that the electric quantity generated by the fuel cell unit is equal to or infinitely close to the required electric quantity.

For example, referring to fig. 4, fig. 4 is a logic diagram of controlling an operation state of a fuel cell unit according to a required electric quantity in the integrated control method of the fuel cell cogeneration system of the present application.

As shown in fig. 4, in one possible embodiment, the step of "controlling the operation state of the fuel cell unit based on the required amount of electricity in the required thermoelectric ratio" further includes:

s301, comparing the required electric quantity with the maximum output electric quantity of the fuel cell unit; when the required electric quantity is greater than the maximum output electric quantity, step S303 is executed, otherwise, when the required electric quantity is less than or equal to the maximum output electric quantity, step S305 is executed.

S303, controlling the fuel cell unit and the auxiliary electric unit to operate together so as to match the required electric quantity.

S305, further comparing the required electric quantity with the minimum output electric quantity of the fuel cell unit; when the required electric quantity is greater than or equal to the minimum output electric quantity, executing step S307; otherwise, when the required power is smaller than the minimum output power, step S309 is executed.

S307 controls the fuel cell unit to operate alone to match the required electric power.

S309, the fuel cell unit is controlled to stop operating.

Specifically, the maximum output power is the power that the fuel cell unit can produce when operating at the maximum output power, which may be obtained based on experimentation or experience. When the required electric quantity is larger than the maximum output electric quantity, the fuel cell unit is proved to run at the maximum output power and cannot meet the electricity demand of a user, and the fuel cell unit and the auxiliary electric unit are controlled to run together at the moment so as to meet the electric quantity required by the user, and meanwhile, the system is ensured to run in a high-efficiency interval.

When the fuel cell unit operates with lower output power, the fuel cell unit is easy to cause loss on the service life of the fuel cell unit, so that when the required electric quantity is smaller than or equal to the maximum output electric quantity, the required electric quantity and the minimum output electric quantity are further judged. The minimum output power, i.e., the power generated by the fuel cell unit operating at the minimum output power, may be obtained based on experimentation or experience. When the required electric quantity is greater than or equal to the minimum output electric quantity, the fuel cell unit is proved to operate in a better power interval, and the electric quantity requirement of a user can be met by independently operating the fuel cell unit, and the fuel cell unit is controlled to independently operate at the moment so as to meet the electric quantity required by the user. When the required electric quantity is smaller than the minimum output electric quantity, the fact that the required electric quantity of a user is lower is proved, the fuel cell unit operates at lower output power, the service life of the fuel cell unit is damaged, and the fuel cell unit is controlled to stop operating at the moment so as to protect the fuel cell unit.

Of course, the above-mentioned deployment method is only a preferred embodiment, and those skilled in the art can adjust the above-mentioned method without departing from the principles of the present application, so that the present application can be adapted to more specific application scenarios. For example, when the required electric quantity is smaller than the maximum output electric quantity, no further judgment may be made, and the operation of the fuel cell unit may be controlled directly based on the required electric quantity.

After the actual power generation amount of the fuel cell unit is controlled to be matched with the required power generation amount, whether the actual power generation amount of the fuel cell unit is consistent with the required heat at the moment can be further judged, and then the operation states of the heat storage unit, the auxiliary heat unit and the heat dissipation cooling unit are controlled according to the judging result.

Specifically, when the fuel cell unit is operated at the optimal thermoelectric ratio, the actual thermoelectric amount may be calculated by the actual power generation amount of the fuel cell and the optimal thermoelectric ratio, wherein the manner of obtaining the actual power generation amount may refer to the current power generation amount. Of course, the actual heat generation amount may be obtained with reference to the above-described current heat generation amount obtaining manner.

After the actual heat generation amount is obtained, the actual heat generation amount is compared with the required heat, for example, the magnitude between the actual heat generation amount and the required heat is compared by calculating a difference value or a ratio. And then controlling the operation states of the heat storage unit, the auxiliary heat unit and the heat dissipation cooling unit based on the comparison result.

Specifically, in one possible embodiment, the step of "controlling the operation states of the heat storage unit, the auxiliary heat unit, and the heat radiation cooling unit based on the comparison result" further includes:

(1) When the actual heat generation amount is larger than the required heat amount, the heat storage unit is controlled to store heat or the heat dissipation cooling unit is controlled to start to operate.

When the actual heat generation amount is larger than the required heat amount, the heat energy generated by the fuel cell unit is proved to be larger than the required heat amount, and at the moment, the redundant heat energy can be stored preferentially, and the residual energy treatment is carried out after the storage is full. For example, the surplus heat may be stored in the heat storage unit, or may be dissipated after the heat is fully stored.

In one possible embodiment, the excess heat may be treated by: acquiring the actual temperature of the heat storage unit; comparing the actual temperature with the set temperature; if the actual temperature is greater than or equal to the set temperature, controlling the heat dissipation cooling unit to start running; and if the actual temperature is smaller than the set temperature, controlling the heat storage unit to store heat.

Specifically, when the actual heat generation amount is greater than the required heat amount, the actual temperature of the heat storage unit is firstly obtained, and then the actual temperature is compared with the set temperature to judge whether the current heat storage unit is sufficient in heat. The set temperature may be a temperature manually set by a user or a temperature preset by a factory. Such as a water temperature of 40-55 c, etc., manually set by the user. If the actual temperature is smaller than the set temperature, the heat of the current heat storage unit is proved to be insufficient, and the heat needs to be supplemented, at the moment, the heat storage unit is controlled to store heat, and the heat generated by the fuel heat pool unit is supplemented to the heat storage unit, so that the redundant heat is stored and utilized, and the overall efficiency of the system is improved. On the contrary, if actual temperature is greater than or equal to the settlement temperature, then prove that the heat of current heat-retaining unit is sufficient, need not to supplement, control heat dissipation cooling unit start-up operation this moment, cool down the inside fuel cell unit, distribute away the surplus heat, prevent that the inside temperature of fuel cell unit is too high.

(2) And when the actual heat generation quantity is smaller than the required heat quantity, controlling the auxiliary heat unit to start heating.

When the actual heat generation amount is smaller than the required heat amount, the heat energy generated by the fuel cell unit is proved to be insufficient to meet the requirement of a user, and at the moment, the part with insufficient heat energy is supplemented by the auxiliary heat unit. For example, the water output from the heat storage unit can be heated by the auxiliary heat unit starting operation.

(3) And when the actual heat generation amount is equal to the required heat, controlling the fuel cell cogeneration system to keep the current operation state.

When the actual heat generation amount is equal to the required heat amount, the current whole fuel cell cogeneration system is proved to be in a more ideal running state, namely the electricity generation and the heat generation are basically equal to the current requirements of users, and the system runs in a relatively balanced state, so that no adjustment is needed.

Here, in the present application, the "actual heat generation amount is equal to the required heat amount" is not strictly static, but is a dynamic one, in other words, as long as the heat generation amount of the fuel cell unit is approximately equal to the required heat amount for use, the two are considered to be equal, that is, the heat generation amount and the heat amount are allowed to float within a certain small deviation.

Of course, the above-mentioned deployment method is only a preferred embodiment, and those skilled in the art can adjust the above-mentioned method without departing from the principles of the present application, so that the present application can be adapted to more specific application scenarios. For example, the fuel cell unit may be directly controlled to stop when the actual heat generation amount is greater than the required heat and the actual temperature of the heat storage unit is greater than the set temperature.

In one possible implementation, after the fuel cell unit stops operating, if the user still has a power demand, the power storage unit or the auxiliary power unit may be turned on to meet the power demand, and a specific selection manner may be referred to in the foregoing embodiments. Similarly, after the fuel cell unit stops running, if the user has a useful heat requirement, the fuel cell unit can be preferentially provided by the heat storage unit, and when the heat storage unit cannot provide the heat (for example, after the water temperature in the heat storage unit is reduced to a certain temperature), the auxiliary heat unit is further started for supplementing.

In summary, according to the method and the device, the required thermoelectric ratio of the user side is compared with the actual thermoelectric ratio of the fuel cell unit, and the operation heat following mode or the electricity following mode of the fuel cell cogeneration system is selectively controlled based on the comparison result, so that the electric heating requirement of the user can be flexibly matched when the method and the device are applied, the application range of a product is improved, the energy waste is reduced, and the maximization of the efficiency of the fuel cell cogeneration system is realized.

Those skilled in the art will appreciate that the various component embodiments of the present application may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art will appreciate that some or all of the functions of some or all of the components in a server, client according to embodiments of the present application may be implemented in practice using a microprocessor or Digital Signal Processor (DSP). The present application may also be embodied as a device or apparatus program (e.g., a PC program and a PC program product) for performing part or all of the methods described herein. Such a program embodying the present application may be stored on a PC readable medium, or may have the form of one or more signals. Such signals may be downloaded from an internet website, provided on a carrier signal, or provided in any other form.

Although the steps are described in the above-described sequential order in the above-described embodiments, it will be appreciated by those skilled in the art that, in order to achieve the effects of the present embodiments, the steps need not be performed in such order, and may be performed simultaneously (in parallel) or in reverse order, and these simple variations are within the scope of the present application.

Furthermore, those skilled in the art will appreciate that while some embodiments described herein include some features but not others included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the present application and form different embodiments. For example, in the claims of the present application, any of the claimed embodiments may be used in any combination.

Thus far, the technical solution of the present application has been described in connection with the preferred embodiments shown in the drawings, but it is easily understood by those skilled in the art that the scope of protection of the present application is not limited to these specific embodiments. Equivalent modifications and substitutions for related technical features may be made by those skilled in the art without departing from the principles of the present application, and such modifications and substitutions will be within the scope of the present application.

Claims (10)

1. A comprehensive control method of a fuel cell cogeneration system is characterized in that the fuel cell cogeneration system comprises a fuel cell unit, a heat storage unit, an auxiliary heat unit, a heat dissipation cooling unit, a power storage unit, an auxiliary power unit and a grid connection unit,

The fuel cell unit can transfer heat to the heat storage unit, the auxiliary heat unit is used for heating water of the heat storage unit, the heat dissipation cooling unit is used for cooling the fuel cell unit, the fuel cell unit can store the generated electricity to the electricity storage unit or access the electricity grid through the grid-connected unit, the auxiliary electricity unit is used for introducing electricity of the electricity grid,

the comprehensive control method comprises the following steps:

acquiring an actual thermoelectric ratio of the fuel cell unit;

acquiring a required thermoelectric ratio between required heat and required electric quantity within a period of time;

comparing the magnitude of the desired thermoelectric ratio to the actual thermoelectric ratio;

and controlling the fuel cell cogeneration system to operate in a thermal following mode or an electric following mode based on the comparison result.

2. The integrated control method of a fuel cell cogeneration system according to claim 1, wherein the step of controlling the fuel cell cogeneration system to operate in a heat following mode or an electricity following mode based on the comparison result further comprises:

controlling the fuel cell cogeneration system to operate in the heat following mode if the required thermoelectric ratio is greater than the actual thermoelectric ratio;

And if the required thermoelectric ratio is smaller than or equal to the actual thermoelectric ratio, controlling the fuel cell cogeneration system to operate in the electric following mode.

3. The integrated control method of a fuel cell cogeneration system according to claim 2, wherein the step of controlling the fuel cell cogeneration system to operate in the heat following mode further comprises:

controlling an operating state of the fuel cell unit based on the required heat in the required heat-to-electricity ratio;

acquiring the actual power generation amount of the fuel cell unit;

judging the actual power generation amount and the required power;

and controlling the running states of the power storage unit, the auxiliary power unit and the grid-connected unit based on the comparison result.

4. The integrated control method of a fuel cell cogeneration system according to claim 3, wherein the step of controlling the operating state of the fuel cell unit based on the required heat in the required heat-to-electricity ratio further comprises:

comparing the required heat with the maximum output heat of the fuel cell unit;

controlling the fuel cell unit to operate together with the auxiliary heat unit to match the required heat when the required heat is greater than the maximum output heat;

When the required heat quantity is smaller than or equal to the maximum output heat quantity, further comparing the required heat quantity with the minimum output heat quantity of the fuel cell unit;

when the required heat is greater than or equal to the minimum output heat, controlling the fuel cell unit to independently operate so as to match the required heat;

and when the required heat quantity is smaller than the minimum output heat quantity, controlling the fuel cell unit to stop running, and controlling the auxiliary heat unit to start running so as to match the required heat quantity.

5. The integrated control method of a fuel cell cogeneration system according to claim 3, wherein the step of controlling the operation states of the electricity storage unit, the auxiliary electricity unit, and the grid-connected unit based on the comparison result further comprises:

when the actual power generation amount is larger than the required power amount, controlling the power storage unit to store power or controlling the grid-connected unit to supply power and grid;

and when the actual power generation quantity is smaller than the required power quantity, controlling the power storage unit to independently supply power or controlling the auxiliary power unit to supply power.

6. The integrated control method of a fuel cell cogeneration system according to claim 5, wherein the step of controlling the electricity storage unit to store electricity or controlling the grid-connected unit to supply electricity to grid-connected further comprises:

Acquiring the residual electric quantity of the electricity storage unit;

comparing the residual electric quantity with an electric quantity upper limit threshold value;

if the residual electric quantity is smaller than the electric quantity upper limit threshold value, controlling the electric storage unit to store electricity;

if the residual electric quantity is larger than or equal to the electric quantity upper limit threshold value, controlling the grid-connected unit to supply power and realize grid connection; and/or

The step of "controlling the power supply of the power storage unit alone or controlling the power supply of the auxiliary power unit" further includes:

acquiring the residual electric quantity of the electricity storage unit;

comparing the residual electric quantity with an electric quantity lower limit threshold value;

if the residual electric quantity is larger than the electric quantity lower limit threshold value, controlling the electricity storage unit to supply power;

and if the residual electric quantity is smaller than or equal to the electric quantity lower limit threshold value, controlling the auxiliary electric unit to supply power.

7. The integrated control method of a fuel cell cogeneration system according to claim 2, wherein the step of controlling the fuel cell cogeneration system to operate in the electric follow mode further comprises:

controlling an operating state of the fuel cell unit based on the required electrical quantity in the required thermoelectric ratio;

Acquiring the actual heat generation amount of the fuel cell unit;

comparing the actual heat generation amount with the required heat;

and controlling the operation states of the heat storage unit, the auxiliary heat unit and the heat dissipation cooling unit based on the comparison result.

8. The integrated control method of a fuel cell cogeneration system according to claim 7, wherein the step of controlling the operating state of the fuel cell unit based on the required electric quantity in the required thermoelectric ratio further comprises:

comparing the required electric quantity with the maximum output electric quantity of the fuel cell unit;

when the required electric quantity is larger than the maximum output electric quantity, controlling the fuel cell unit and the auxiliary electric unit to operate together so as to match the required electric quantity;

when the required electric quantity is smaller than or equal to the maximum output electric quantity, further comparing the required electric quantity with the minimum output electric quantity of the fuel cell unit;

when the required electric quantity is greater than or equal to the minimum output electric quantity, controlling the fuel cell unit to independently operate so as to match the required electric quantity;

and when the required electric quantity is smaller than the minimum output electric quantity, controlling the fuel cell unit to stop running, and controlling the auxiliary electric unit to start running so as to match the required electric quantity.

9. The integrated control method of a fuel cell cogeneration system according to claim 7, wherein the step of controlling the operation states of the heat storage unit, the auxiliary heat unit, and the heat radiation cooling unit based on the comparison result further comprises:

when the actual heat generation amount is larger than the required heat amount, controlling the heat storage unit to store heat or controlling the heat dissipation cooling unit to start running;

and when the actual heat generation amount is smaller than the required heat amount, controlling the auxiliary heat unit to start heating.

10. The integrated control method of a fuel cell cogeneration system according to claim 9, wherein the step of controlling the heat storage unit to store heat or controlling the heat radiation cooling unit to start operation further comprises:

acquiring the actual temperature of the heat storage unit;

comparing the actual temperature with a set temperature;

if the actual temperature is greater than or equal to the set temperature, controlling the heat dissipation cooling unit to start running;

and if the actual temperature is smaller than the set temperature, controlling the heat storage unit to store heat.

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