KR101567237B1 - Apparatus and method for detecting lack of cooling water in the thermal management system for fuel cell - Google Patents

Abstract

The present invention relates to an apparatus and method to detect a lack of cooling water of a fuel cell vehicle and, more specifically, relates to an apparatus and a method to detect a lack of cooling water of a fuel cell vehicle; and moreover, accurately detecting a state where cooling water is lacking when driving on a regular road and on an irregular road, distinguished from each other. The apparatus to detect the lack of cooling water of the fuel cell vehicle comprises: a first pressure sensor; a water level sensor or a second pressure sensor; and a controller. The first pressure sensor is installed in a cooling water circulation line positioned between a fuel cell stack and a radiator to detect a pressure of flowing cooling water. The water level sensor detects the water level of the cooling water in a reservoir connected to the radiator to supplement cooling water. The second pressure sensor detects the pressure of the cooling water. The controller determines the state where the vehicle is driven on the rough road when the water level of the cooling water in the reservoir, which is detected by the water level sensor, and the pressure of the cooling water, which is detected by the second pressure sensor, is repeatedly increased to be a preset reference value or more. The controller distinguishes the drive on the irregular road and a drive on a flat road, and determines whether a lack of cooling water is based on the pressure of the flowing cooling water which is detected by the first pressure sensor in accordance with each set′s detection logic.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an apparatus and a method for detecting a shortage of cooling water in a fuel cell vehicle,

The present invention relates to an apparatus and method for detecting a shortage of coolant in a fuel cell vehicle, and more particularly, to an apparatus and method for detecting a shortage of coolant in a fuel cell vehicle, .

As is known, a fuel cell system mounted in a fuel cell vehicle includes a fuel cell stack for generating electrical energy from an electrochemical reaction of a reactive gas, a hydrogen supply device for supplying hydrogen as fuel to the fuel cell stack, And a heat and water management system for discharging heat of the fuel cell stack to the outside to optimally control the operating temperature and to perform a water management function.

In a conventional vehicle fuel cell system, a hydrogen supply device supplies high-pressure hydrogen stored in a hydrogen tank to a fuel cell stack by regulating pressure through a regulator. The air supply device humidifies air supplied by an air blower through a humidifier, To the battery stack.

The fuel cell vehicle also has an inverter that uses an electric motor as a driving source for running and converts the direct current voltage of the fuel cell stack or the battery into an alternating current voltage to drive the electric motor.

In addition, the fuel cell stack discharges heat and water as reaction byproducts during the electrochemical reaction of hydrogen and oxygen, which are reactors. In order to achieve optimal output performance of the stack, it is necessary to control the temperature of the stack during start- And the discharge of water (stack generated water) generated inside the stack should be smooth.

Therefore, it is essential to use a heat and water management system to rapidly raise the stack temperature at start-up, to maintain the stack temperature at the optimum temperature during operation, and to discharge the stack generated water to the outside.

1, a radiator 11 and a radiator fan 12 for discharging the heat of the cooling water to the outside are installed in the heat and water management system to maintain the temperature of the fuel cell stack at an appropriate temperature. A cooling water circulation line 13 connected between the fuel cell stack 10 and the radiator 11 so as to circulate the cooling water therethrough and a bypass line 14 for selectively bypassing the cooling water so as not to pass through the radiator 11 And a three-way valve 15, and a water pump 16 for pumping and circulating cooling water.

In such a fuel cell cooling apparatus, the water pump 16 is driven to circulate the cooling water along the cooling water circulation line 13 between the fuel cell stack 10 and the radiator 11 and the three-way valve 15, And radiates heat generated in the radiator 11 through the radiator 11 to the outside.

The radiator fan 12 is driven while the cooling water is circulated for cooling the fuel cell stack 10 in the water-cooled cooling apparatus described above, and the outside air or the air flowing in by the radiator fan 12 from the radiator 11 And the heat of the cooling water is discharged to the outside through the heat exchange with the wind.

In this process, the controller (not shown) inputs the stack temperature detected by the sensor, and controls the water pump 16, the radiator fan 12, the three-way valve (15) and so on to perform stack cooling through the cooling water.

The cooling water circulation line 13 is provided with a heater 17 for rapidly heating the temperature of the fuel cell stack 10 to an appropriate operating temperature and for heating the cooling water flowing into the fuel cell stack.

When the temperature of the fuel cell stack 10 is in a low temperature state, the opening direction of the 3-way valve 15 is controlled to block the cooling water discharged from the radiator outlet, and the water pump 16 is connected to the bypass line 14 The cooling water is sucked, pumped, circulated, and the heater 17 is operated to heat the cooling water flowing into the fuel cell stack, thereby rapidly warming up the fuel cell stack.

The cooling water replenishing line 19 is connected to the upper end of the radiator through the pressure cap 18 and the reservoir 20 and the reservoir 20 for storing the cooling water is provided in the air opening type structure, (21) is mounted.

In this configuration, when the cooling water in the stack cooling loop is lost, negative pressure is applied to the front end line of the water pump 16, and cooling water in the reservoir 20 flows through the cooling water supplement line 19 and the pressure cap 18 to the radiator 11 ) To replenish the lost cooling water.

On the other hand, when the cooling water in the reservoir 20 is rapidly discharged, there is a problem that the water level sensor 21 for detecting the cooling water level in the reservoir malfunctions due to repeated circulation such as generation of a large amount of bubbles and water swirling.

In order to solve these problems, the prior art document of Patent Publication No. 10-2013-0124789 (Nov. 13, 2013) includes a pressure sensor installed in the cooling water circulation line, and based on the variation of the pressure sensor signal and the number of tilt changes A technique for judging the shortage of cooling water is disclosed.

Further, in the above prior art document, a cooling water replenishing line is connected to the upper end of the radiator, and a pressure cap to be opened by a certain pressure is mounted on a radiator connecting portion to which a cooling water replenishing line is connected.

Thus, the stack cooling system of the fuel cell vehicle is composed of an air atmosphere system including a closed system of a stack cooling loop (pressurized loop), a cooling water replenishment line and a reservoir (atmospheric pressure loop) based on the pressure cap of the radiator.

In this configuration, the cooling water in the reservoir enters the cooling water circulation line through the pressure cap at the time of the cooling water replenishment, and the water vapor enters the reservoir at the high temperature of the cooling water, thereby minimizing the cooling water flow noise and the cooling water evaporation amount.

However, in the technology using the signal of the pressure sensor installed in the cooling water circulation line as in the prior art document, the signal of the pressure sensor is shaken due to the severe vibration of the vehicle during the rough driving, .

In order to solve the diagnosis of the lack of cooling water at the time of running on such an obstacle, the sensing sensitivity of the logic for sensing the lack of cooling water can be mitigated and applied as suggested in the above prior art documents.

That is, it is possible to obtain a shortage of cooling water from the number of sign changes of the pressure sensor signal and the slope value by applying a large reference value (a reference number for comparing the number of sign changes of the slope value and a reference pressure value for comparing the pressure difference of the front and rear data) Thereby slowing the detection sensitivity.

However, applying the relaxed sensing sensitivity has a problem that the lack of cooling water can not be diagnosed even when a small amount of cooling water is actually insufficient.

Korean Patent Publication No. 10-2013-0124789 (November 13, 2013)

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide an apparatus and method for detecting a shortage of coolant in a fuel cell vehicle, There is a purpose.

According to an aspect of the present invention, there is provided a fuel cell system comprising: a first pressure sensor installed in a cooling water circulation line between a fuel cell stack and a radiator to detect a cooling water flow pressure; A water level sensor for sensing the level of the cooling water in the reservoir connected to the radiator for replenishing the cooling water or a second pressure sensor for detecting the cooling water pressure; And a controller for determining that the vehicle is in a rough running state when the water level of the cooling water in the reservoir detected by the water level sensor or the cooling water pressure detected by the second pressure sensor is repeatedly increased or decreased by a predetermined reference level or more Wherein the controller determines whether the cooling water is insufficient from the cooling water flow pressure detected through the first pressure sensor in accordance with the detection logic that is set for each of the running route and the flat running mode. to provide.

According to another aspect of the present invention, there is provided a method for controlling a fuel cell stack, comprising: detecting a coolant flow pressure through a first pressure sensor installed in a coolant circulation line between a fuel cell stack and a radiator; Detecting a coolant water level in the reservoir or detecting a coolant pressure through a level sensor or a second pressure sensor provided in a reservoir connected to the radiator for replenishing the coolant; Determining whether the vehicle is running on a rough road by confirming whether the cooling water level in the reservoir detected by the level sensor or the cooling water pressure detected by the second pressure sensor is repeatedly increased or decreased by a predetermined reference level or more; And determining whether the cooling water is insufficient from the cooling water flow pressure detected through the first pressure sensor by selectively using sensing logic that is divided into the rough road driving mode and the flat driving mode according to the determination result of the rough road running, Thereby providing a method for detecting the lack of coolant in the battery vehicle.

Accordingly, the apparatus and method for sensing the shortage of coolant in the fuel cell vehicle according to the present invention have the following effects.

In the conventional logic for insufficient cooling water determination, there is a problem of misdiagnosis which can not diagnose the lack of the actual amount of cooling water due to application of a single variable logic without distinguishing between the general road and the rough road driving. However, in the present invention, It is possible to solve the problem of misdiagnosis by selectively applying the logic according to the road driving condition after distinguishing the road from the rough road.

In particular, since the sensing sensitivity of the logic can be adjusted according to road driving conditions, it is possible to determine the insufficient cooling water for the leakage amount of the fine cooling water by improving sensitivity in the case of running on the general road. As a result, it is possible to prevent problems such as occurrence of hot spots in advance.

In addition, it is possible to set various levels of logic when tuning and setting the reference value (reference frequency and reference pressure value) of the logic according to the degree of roughness as well as whether it is running on the rough road. .

The present invention can be applied not only to a fuel cell vehicle but also to any vehicle to which a water-cooled cooling system is applied.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a view showing a configuration of a conventional thermal management system; FIG.
2 is a configuration diagram of a thermal management system to which a cooling water shortage sensing apparatus according to an embodiment of the present invention is applied.
FIG. 3 is a view for explaining a method for judging whether or not an obstacle is running on the basis of a sensor signal in the present invention.
FIG. 4 is a graph illustrating the comparison of sensor signals when traveling on an ordinary road and on an off-road in the present invention.
5 is a configuration diagram of a thermal management system to which a cooling water shortage sensing apparatus according to another embodiment of the present invention is applied.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains.

2 is a block diagram of a thermal management system using a cooling water shortage sensing apparatus according to an embodiment of the present invention. As shown in FIG. 2, a cooling water shortage sensing apparatus according to an embodiment includes a cooling water circulation line 13, And a first pressure sensor 22 for detecting pressure along the flow.

In the present invention, the controller determines the state of insufficient cooling water from the signal of the first pressure sensor (22). More specifically, the controller notifies the controller of the change of the pressure detection signal input from the first pressure sensor (22) The number of changes is analyzed to detect the shortage of cooling water.

In addition, the cooling water shortage sensing apparatus according to the embodiment includes water level sensors 23 and 24 mounted at the upper and lower positions of the reservoir 20, and the water level sensors 23 and 24 are water- And outputs electrical signals, that is, a dry signal and a water sensing signal, which are distinguished according to the state (absence of water).

Hereinafter, the water level sensor 23 provided at the upper position of the reservoir 20 will be referred to as an upper water level sensor, and the water level sensor 24 provided at the lower side will be referred to as a lower water level sensor.

An optical water level sensor may be used as the two water level sensors 23 and 24, and the optical water level sensor operates using the principle of refraction of light. The optical level sensor includes a light emitting part inserted into the reservoir 20 and emitting light to the cooling water, And a prism structure having a light receiving portion for receiving the light and allowing light to be refracted from the light emitting portion to the light receiving portion as in a normal optical water level sensor.

The optical water level sensor outputs an electrical signal indicative of the presence or absence of cooling water in the reservoir 20 by distinguishing the difference in luminous intensity between the presence of cooling water and the absence of cooling water (dry state) And the water sensing signal is received by the controller.

The controller is driving the vehicle from the signal of the two water level sensors 23 and 24, that is, the signals of the upper water level sensor 23 and the lower water level sensor 24, in order to detect the cooling water shortage state, It is judged whether or not the vehicle is in a running state or in a rough road.

3, when the upper water level sensor 23 and the lower water level sensor 24 are installed in the open reservoir 20, the upper water level sensor 23 and the lower water level sensor 24 are disposed at the upper water level A dry signal for the sensor 23, and a water sensing signal for the lower level sensor 24.

On the other hand, since the water level fluctuation lines ('a' and 'b') of FIG. 3 cause a severe fluctuation of the water level due to the swinging of the cooling water in the reservoir 20, both of the water level sensors 23 and 24, And outputs the detection signal repeatedly.

Therefore, when the level of the cooling water in the reservoir 20 is repeatedly increased or decreased from the signal of the water level sensors 23 and 24 to a predetermined reference level or higher, it can be determined that the controller is driving the vehicle on the rough road.

Therefore, in the present invention, when the controller senses a state in which there is little fluctuation in the water level change through the water level sensors 23 and 24, more specifically, when the dry signal is detected from the upper water level sensor 23, When the signal is continuously inputted, it is set so as to judge that the vehicle is traveling on a general road.

When the controller senses a state in which the coolant water level is repeatedly increased or decreased to a predetermined reference level or higher through the water level sensors 23 and 24, When the detection signal is repeatedly input, it is set so as to judge that the vehicle is at the time of rough driving.

The upper level sensor 23 and the lower level sensor 24 are provided on the opposite sides of the reservoir 20 in order to judge whether the vehicle is running on the rough road from the above-described level fluctuation state sensed by the level sensors 23, As shown in FIG.

When the dry level signal from the upper level sensor 23 and the water level signal from the lower level sensor 24 are continuously inputted, the upper level sensor 23 determines that the dry signal and the water level signal It may be set to judge that the vehicle is running on rough roads.

4 (a), the upper level sensor 23 and the lower level sensor 24 are driven by a dry signal ('dry') and a lower level sensor 24, respectively, when the vehicle is traveling on an ordinary road. ('Wet'). However, as shown in (b), both of the water level sensors 23 and 24 repeatedly output a dry signal and a water sensing signal at the time of rough driving.

5 is a block diagram of a thermal management system to which a cooling water shortage sensing device according to another embodiment of the present invention is applied. In this embodiment, a pressure sensor 25 is used instead of a water level sensor in the reservoir 20 .

A second pressure sensor 25 for detecting the pressure applied by the cooling water is provided at the position of the lower end of the reservoir 20 and the controller discriminates from the signal of the second pressure sensor 25 .

At this time, the controller determines that the pressure value (the cooling water pressure in the reservoir) detected by the second pressure sensor 25 is in a state of repeatedly increasing or decreasing to a predetermined reference level or higher,

More specifically, at the time of traveling on a general road, the cooling water in the reservoir 20 scarcely rises and there is no serious fluctuation of the water level, so that the signal value of the second pressure sensor 25 becomes almost constant without fluctuation or fluctuation.

On the other hand, at the time of running on the rough road, since the cooling water in the reservoir 20 slips and shakes, the level of the water level fluctuates severely, so that the signal of the second pressure sensor 25 is shaken more than the reference level.

Therefore, in the case of using the pressure sensor (second pressure sensor), the controller determines that the number of sign changes and the variation width (pressure difference in the front and rear data) of the slope value of the continuous pressure data change monitored through the second pressure sensor 25 are If the reference number is equal to or greater than the reference pressure value, it is determined that the vehicle is traveling on an ordinary road.

Meanwhile, in the present invention, differentiated logic is selectively applied according to whether the vehicle is traveling on a rough road to detect a shortage of cooling water.

That is, by controlling the sensing sensitivity of the logic to detect the shortage of cooling water depending on whether or not the vehicle is running on the rough road, in the case of judging the shortage of the cooling water, the controller uses the logic that mitigates the sensibility of sensing, If the vehicle is traveling on a public road again, it recognizes it and uses the logic to improve the detection sensitivity again.

First, the pressure of the cooling water flow in the first pressure sensor 22 is detected, and the pressure detection signal of the first pressure sensor 22 is input to the controller.

The controller determines that the coolant is insufficient when the pressure value (the coolant flow pressure of the coolant circulation line) detected by the first pressure sensor 22 is repeatedly increased or decreased by a predetermined reference level or higher.

More specifically, when the cooling water is buffered in the stack cooling loop, as shown in FIG. 6, the cooling water flow pressure detected by the first pressure sensor 22 also increases when the pump rotation speed RPM increases, It is judged that the cooling water is insufficient because there is almost no fluctuation of the pressure.

On the other hand, when the cooling water is insufficient due to evaporation or leakage of the cooling water in the stack cooling loop, a change in the cooling water flow pressure detected by the first pressure sensor 22 occurs significantly as shown in Fig. 7, Increase or decrease occurs.

That is, the slope value sign of the cooling water pressure change detected by the first pressure sensor 22 frequently changes, and the variation width of the pressure is excessively generated.

Therefore, the controller receiving the detection data of the first pressure sensor 22 can determine whether the cooling water is insufficient by using the slope value and the variation width of the pressure change of the detected data.

In the embodiment, the controller diagnoses whether or not the cooling water is insufficient by using the sign change of the slope value of the continuous pressure data change monitored in real time through the first pressure sensor 22 and the pressure difference (change width) of the front and rear data.

More specifically, when the controller determines that the vehicle is traveling on an ordinary road, the sensed sensitivity enhancement logic is applied so that the detected data value of the first pressure sensor 22 received by the controller for 5 seconds is X _n to X _{n + 9} Quot; and " abs (X _{n +1} -X _n )> the first reference pressure value is equal to or greater than the second reference number of times] "if" [the sign of X _{n +1} -X _n is changed more than the first reference number] The controller makes a primary determination that the coolant is low and lights the cluster warning light to warn the driver.

In the sensing sensitivity enhancement logic, the first reference number, the second reference number, and the first reference pressure value are set to a third reference number, a fourth reference number, and a second reference pressure value, respectively, of the sensing sensitivity relaxation logic .

For example, when the first reference number is 3, the third reference number is 5, when the second reference number is 2, the fourth reference number is 4, and when the first reference pressure value is 0.02 bar, The value can be set to 0.03 bar respectively.

Next, after the above-described driver warning step, if it is determined that the cooling water continues to be insufficient, the step of limiting the output of the fuel cell stack 10 proceeds.

In the embodiment, when the number of the first determination that the cooling water is insufficient is greater than or equal to the threshold number, the controller proceeds to logic for limiting the output of the fuel cell stack 10.

For example, if it is determined that the cooling water is insufficient six times out of the total of ten times of the first judgment that the cooling water is insufficient, and the warning lamp is turned on, the controller proceeds to logic for limiting the output of the fuel cell stack 10.

Alternatively, as another embodiment, if the average pressure of five or more continuous pressure data detected in real time by the first pressure sensor 22 is at the normal pressure (1 bar) and at the same time, the rotation speed RPM of the water pump 16 is equal to or higher than the reference value , The controller proceeds to logic that limits the output of the fuel cell stack 10.

That is, when the pressure data value of the first pressure sensor 22 received by the controller is X _n to X _{n + 9} , "[avg (X _{n +5} to X _{n +9} ) Pump rotational speed> 1600 (rpm)], the controller proceeds to logic for limiting the output of the fuel cell stack 10.

More specifically, the average pressure (bar) of the five consecutive data (X _{n +5} to X _{n +9} ) selected from among the continuous pressure data X _n to X _{n +9} detected in real time in the first pressure sensor 22 is (Rpm) of the water pump 16 is equal to or higher than the reference value (1,600 rpm), the secondary determination is made that the cooling water continues to be insufficient and the output of the fuel cell stack 10 is limited The logic proceeds.

At this time, the mean pressure of the continuous data (X _{n +5} to X _{n +9} ) means 1 because it is in a state where the cooling water flow pressure can not be detected due to insufficient cooling water.

On the other hand, when the controller judges at the time of running on the rough road, when the sensed sensitivity relaxation logic is applied and the detected data value of the first pressure sensor 22 received by the controller for 5 seconds is X _n to X _{n + 9} , _{n + 1} -X _n is changed more than the third reference number] and [abs (X _{n +1} -X _n )> second reference pressure value occurs more than the fourth reference number]], And makes the warning light of the cluster light for driver warning.

Next, after the above-described driver warning step, if it is determined that the cooling water continues to be insufficient, the step of limiting the output of the fuel cell stack 10 proceeds.

In the embodiment, if the number of the first determination that the coolant is insufficient is greater than or equal to the threshold number, the controller proceeds to logic for limiting the output of the fuel cell stack 10, which is the same logic as that for running on a general road.

That is, when it is determined that the cooling water is insufficient six times out of the total of ten times of the first judgment that the cooling water is insufficient, and the warning lamp is turned on, the controller proceeds to logic for limiting the output of the fuel cell stack 10.

Alternatively, as another embodiment, if the average pressure of five or more continuous pressure data detected in real time by the first pressure sensor 22 is at the normal pressure (1 bar) and at the same time, the rotation speed RPM of the water pump 16 is equal to or higher than the reference value , The controller proceeds to logic that limits the output of the fuel cell stack 10.

That is, when the pressure data value of the first pressure sensor 22 received by the controller is X _n to X _{n + 9} , "[avg (X _{n +5} to X _{n +9} ) Pump rotational speed> 1600 (rpm)], the controller proceeds to logic for limiting the output of the fuel cell stack 10.

More specifically, the average pressure (bar) of the five consecutive data (X _{n +5} to X _{n +9} ) selected from among the continuous pressure data X _n to X _{n +9} detected in real time in the first pressure sensor 22 is (Rpm) of the water pump 16 is equal to or higher than the reference value (1,600 rpm), the secondary determination is made that the cooling water continues to be insufficient and the output of the fuel cell stack 10 is limited The logic proceeds.

Thus, in the conventional logic for insufficient cooling water determination, there is a problem of misdiagnosis which can not diagnose the lack of the actual amount of cooling water due to application of a single variable logic without distinguishing between the general road and the rough road. However, , The problem of misdiagnosis can be solved by selectively applying the logic according to road driving conditions after distinguishing between the general road and the rough road driving.

In particular, since the sensing sensitivity of the logic can be adjusted according to road driving conditions, it is possible to determine the insufficient cooling water for the leakage amount of the fine cooling water by improving sensitivity in the case of running on the general road. As a result, it is possible to prevent problems such as occurrence of hot spots in advance.

In addition, it is possible to set various levels of logic when tuning and setting the reference value (reference frequency and reference pressure value) of the logic according to the degree of roughness as well as whether it is running on the rough road. .

The present invention can be applied not only to a fuel cell vehicle but also to any vehicle to which a water-cooled cooling system is applied.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the scope of the present invention is not limited to the disclosed exemplary embodiments. Forms are also included within the scope of the present invention.

10: Fuel cell stack 11: Radiator
12: radiator fan 13: cooling water circulation line
14: bypass line 15: 3-way valve
16: water pump 17: heater
18a: pressure cap 19: cooling water replenishment line
20: reservoir 22: first pressure sensor
23: upper level sensor 24: lower level sensor
25: second pressure sensor

Claims (20)

delete A first pressure sensor installed in the cooling water circulation line between the fuel cell stack and the radiator to detect the cooling water flow pressure;
A water level sensor for sensing the level of the cooling water in the reservoir connected to the radiator for replenishing the cooling water or a second pressure sensor for detecting the cooling water pressure;
And a controller for determining that the vehicle is in a rough running state when the water level of the cooling water in the reservoir detected by the water level sensor or the cooling water pressure detected by the second pressure sensor is repeatedly increased or decreased by a predetermined reference level or more ,
The controller discriminates whether the cooling water is insufficient from the cooling water flow pressure detected through the first pressure sensor in accordance with the sensing logic set for each of the running route and the flat traveling mode,
And an upper level sensor and a lower level sensor provided at the upper position and the lower position of the reservoir as the level sensor,
Wherein the controller determines that the vehicle is in the rough driving state when both the upper level sensor and the lower level sensor input the dry signal and the water sensing signal repeatedly.
The method of claim 2,
Wherein the controller determines that the vehicle is in a running state in a flat state when a dry signal is input from an upper level sensor and a water detection signal is input from a lower level sensor.
A first pressure sensor installed in the cooling water circulation line between the fuel cell stack and the radiator to detect the cooling water flow pressure;
A water level sensor for sensing the level of the cooling water in the reservoir connected to the radiator for replenishing the cooling water or a second pressure sensor for detecting the cooling water pressure;
And a controller for determining that the vehicle is in a rough running state when the water level of the cooling water in the reservoir detected by the water level sensor or the cooling water pressure detected by the second pressure sensor is repeatedly increased or decreased by a predetermined reference level or more ,
The controller discriminates whether the cooling water is insufficient from the cooling water flow pressure detected through the first pressure sensor in accordance with the sensing logic set for each of the running route and the flat traveling mode,
And an upper level sensor and a lower level sensor provided at the upper position and the lower position of the reservoir as the level sensor,
The controller determines that the vehicle is in a flat running state when a dry signal is input from the upper level sensor and a water detection signal is input from the lower level sensor and when the dry signal and the water detection signal are repeatedly inputted from the upper level sensor, And determines that the vehicle is running on the rough road.
The method according to claim 2 or 4,
The controller comprising:
When the number of sign changes of the slope value of the continuous pressure data changes monitored through the second pressure sensor is equal to or greater than a predetermined reference number and the pressure difference between the front and rear data is equal to or greater than the reference pressure value, And determines that the vehicle is running on the rough road.
The method of claim 5,
The controller comprising:
Wherein the controller determines that the fuel cell vehicle is in a flat running state when the number of sign changes of the slope value of the pressure data change and the pressure difference between the front and rear data are less than the reference number and the reference pressure value, respectively.
The method according to claim 2 or 4,
Wherein the sensing logic is set to determine whether the cooling water is insufficient by using the slope value and the variation width of the continuous pressure data change monitored through the first pressure sensor.
The method of claim 7,
The controller comprising:
If it is determined that the vehicle is in a flat running state,
Wherein the number of times that the sign change of the slope value of the continuous pressure data change monitored through the first pressure sensor is equal to or greater than a first reference number and the number of times the pressure difference of the front and rear data is equal to or greater than the first reference pressure value, And determines that the cooling water is in a state of insufficient cooling water if the number of times of the cooling water is more than the predetermined number.
The method of claim 8,
The controller comprising:
If it is determined that the vehicle is in the rough driving state,
Wherein the number of times the sign change of the slope value of the continuous pressure data change monitored through the first pressure sensor is equal to or greater than a third reference number and the number of times that the pressure difference of the front and rear data is equal to or greater than the second reference pressure value, And determines that the cooling water is in a state of insufficient cooling water if the number of times of the cooling water is more than the predetermined number.
The method of claim 9,
Wherein the first reference number is less than a third reference number, the second reference number is less than a fourth reference number, and the first reference pressure value is set to a value smaller than the second reference pressure value. Coolant shortage detection device.
delete Detecting a coolant flow pressure through a first pressure sensor installed in a coolant circulation line between the fuel cell stack and the radiator;
Detecting a coolant water level in the reservoir or detecting a coolant pressure through a level sensor or a second pressure sensor provided in a reservoir connected to the radiator for replenishing the coolant;
Determining whether the vehicle is running on a rough road by confirming whether the cooling water level in the reservoir detected by the level sensor or the cooling water pressure detected by the second pressure sensor is repeatedly increased or decreased by a predetermined reference level or more;
Determining whether the cooling water is insufficient from the cooling water flow pressure detected through the first pressure sensor by selecting the sensed logic by dividing the traveling route between the running route and the flat traveling according to the determination result of whether or not to travel on the rough route;
/ RTI >
An upper water level sensor and a lower water level sensor provided at the upper and lower positions of the reservoir are used as the water level sensor,
Wherein when the dry signal and the water detection signal are repeatedly inputted to both the upper level sensor and the lower level sensor, it is determined that the vehicle is in a rough driving state.
The method of claim 12,
Wherein the control unit determines that the vehicle is in a flat running state when a dry signal is input from the upper level sensor and a water detection signal is input from the lower level sensor.
Detecting a coolant flow pressure through a first pressure sensor installed in a coolant circulation line between the fuel cell stack and the radiator;
Detecting a coolant water level in the reservoir or detecting a coolant pressure through a level sensor or a second pressure sensor provided in a reservoir connected to the radiator for replenishing the coolant;
Determining whether the vehicle is running on a rough road by confirming whether the cooling water level in the reservoir detected by the level sensor or the cooling water pressure detected by the second pressure sensor is repeatedly increased or decreased by a predetermined reference level or more;
Determining whether the cooling water is insufficient from the cooling water flow pressure detected through the first pressure sensor by selecting the sensed logic by dividing the traveling route between the running route and the flat traveling according to the determination result of whether or not to travel on the rough route;
/ RTI >
An upper water level sensor and a lower water level sensor provided at the upper and lower positions of the reservoir are used as the water level sensor,
If the dry signal is input from the upper level sensor and the water sensing signal is input from the lower level sensor, the vehicle is in a flat running state, and if the upper level sensor repeatedly inputs the dry signal and the water sensing signal, And determining that the fuel cell vehicle is in a running state.
The method according to claim 12 or 14,
When the number of sign changes of the slope value of the continuous pressure data changes monitored through the second pressure sensor is equal to or greater than a predetermined reference number and the pressure difference between the front and rear data is equal to or greater than the reference pressure value, And determining that the fuel cell vehicle is in a rough running state.
16. The method of claim 15,
Wherein when the number of times of sign change of the slope value of the pressure data change and the pressure difference of the front and rear data are less than the reference number and the reference pressure value, it is determined that the vehicle is in a flat running state.
The method according to claim 12 or 14,
Wherein the sensing logic is configured to determine whether the cooling water is insufficient by using the slope value and the variation width of the continuous pressure data change monitored through the first pressure sensor.
18. The method of claim 17,
If it is determined that the vehicle is in a flat running state,
Wherein the number of times that the sign change of the slope value of the continuous pressure data change monitored through the first pressure sensor is equal to or greater than a first reference number and the number of times the pressure difference of the front and rear data is equal to or greater than the first reference pressure value, And judging that the cooling water is in a state of insufficient cooling water if the number of times of cooling water is more than the predetermined number.
19. The method of claim 18,
If it is determined that the vehicle is in the rough driving state,
Wherein the number of times the sign change of the slope value of the continuous pressure data change monitored through the first pressure sensor is equal to or greater than a third reference number and the number of times that the pressure difference of the front and rear data is equal to or greater than the second reference pressure value, And judging that the cooling water is in a state of insufficient cooling water if the number of times of cooling water is more than the predetermined number.
The method of claim 19,
Wherein the first reference number is less than a third reference number, the second reference number is less than a fourth reference number, and the first reference pressure value is set to a value smaller than the second reference pressure value. Cooling water shortage detection method.

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