MONITORING SYSTEM FOR THE OPERATING STATUS OF A COOLING DEVICE FOR THE HEAT TRANSFER FLUID OF A COOLING CIRCUIT

Abstract

The invention relates to a system for monitoring the operating status of a cooling device for the heat transfer fluid of a cooling circuit of an electric, hybrid or fuel cell motor vehicle, said vehicle having a valve (V) capable of having a first position and a second position; said valve moving from the first position to the second position when the temperature of the battery measured by said thermal probe is above a predetermined threshold temperature, said supervisor being configured to compare the temperature values ​​from the first temperature sensor and the third temperature sensor to monitor the operating status of said cooling device.The invention also relates to a method for monitoring the operating status of a cooling device for the heat transfer fluid in a cooling circuit of an electric, hybrid or fuel cell motor vehicle. Figure 1.

Description

Title of the invention: MONITORING SYSTEM FOR THE OPERATING STATUS OF A COOLING DEVICE FOR THE HEAT TRANSFER FLUID OF A COOLING CIRCUIT

[0001] The invention relates to the cooling circuits of electric, hybrid or fuel cell motor vehicles.

[0002] Prior art patent application US2018006347 is known, which describes a control of the traction battery cooling circuit of a vehicle. The vehicle includes a refrigeration system comprising a compressor, a condenser, a cooler, and a cabin evaporator. The vehicle also includes a cooling system comprising a valve. The valve includes an inlet connected to said battery, a first outlet, and a second outlet such that the refrigerant flows into the first outlet or the second outlet depending on the position of the valve. In addition, the cooling system includes a cooler loop connected to the first outlet and a radiator loop connected to the second outlet. Temperature sensors are located upstream and downstream of the battery. The valve is actuated when the refrigerant temperature exceeds a target refrigerant temperature.However, one drawback remains. The invention does not allow for determining, in the event of a problem regulating the battery temperature, whether the fault originates from the battery or the cooler.

[0003] The objective of the present invention is to remedy these drawbacks and to enable the detection of a malfunction of the cooling device of a cooling circuit.

[0004] To achieve this objective, the invention proposes a system for monitoring the operating status of a cooling device for the heat transfer fluid in a cooling circuit of an electric, hybrid, or fuel cell motor vehicle, said vehicle comprising a powertrain including a traction battery and a supervisor, said traction battery including a temperature sensor, said supervisor including a management module, notable in that said management module includes a valve configured to interact with a degassing unit, a first circuit for regulating the passenger compartment temperature, a second circuit for cooling said powertrain, and a third circuit for regulating the temperature of said traction battery, said first circuit including the cooling device, a heating device, a air heater and a first temperature sensor, the second circuit comprising an electrical converter, an electrical machine, a radiator and a second temperature sensor, said third circuit comprising a third temperature sensor and said traction battery, said valve being configured to manage the connections between said first circuit, said second circuit, said third circuit and said degassing unit, said valve being capable of having two positions: - a first position in which the first circuit is independent of the second circuit, the third circuit and the degassing box, the second circuit being independent of the first circuit and the third circuit, said second circuit being connected to the degassing box via the radiator, the third circuit being independent of the first circuit, the second circuit and the degassing box, said cooling device being configured to cool the heat transfer fluid of the first circuit, said heating device being configured to heat the heat transfer fluid of the first circuit; - a second position in which the first circuit is connected to the third circuit, the degassing box being connected to the circuit formed by the first circuit and the third circuit, said cooling device being configured to cool the heat transfer fluid of the first circuit, the second circuit and the third circuit, said heating device being configured to heat the heat transfer fluid of the first circuit and the third circuit; said valve moving from the first position to the second position when the battery temperature measured by said thermal probe is above a predetermined threshold temperature, said supervisor being configured to measure a temperature difference between a temperature of the first circuit T1 from the first temperature sensor and a temperature of the third circuit T3 from the third temperature sensor and to calculate a cooling efficiency rate TER to monitor the operating status of said cooling device.

[0005] Thanks to the invention, when the cooling circuit is active, the position of the valve and the configuration of the circuits make it possible to monitor the operating state of the cooling device.

[0006] Preferably, in the first position, the first circuit comprises a first connection between said valve and said first temperature sensor and a second connection between said air heater and said valve, said second circuit comprising a third connection between said valve and said second temperature sensor, a fourth connection between the output of the electric machine and said valve and a fifth connection between said radiator and said valve, the third circuit comprising a sixth connection between said valve and said third temperature sensor and a seventh connection between said traction battery and the valve, said degassing box having an eighth connection between said degassing box and said valve, and, in the second position, the seventh connection being connected to the first connection, the second connection being connected to the sixth connection, the eighth connection being connected to the first connection, the fifth connection being connected to the third connection, said fourth connection being closed.

[0007] This configuration allows the different circuits to be modified by a simple change of position of the valve.

[0008] Furthermore, the invention relates to a method for monitoring the operating status of a cooling device for the heat transfer fluid of a cooling circuit of an electric, hybrid or fuel cell motor vehicle, by means of a system for monitoring the operating status of a cooling device previously described, said battery having a temperature above said predetermined threshold temperature, remarkable in that said method comprises the following steps: - a step of measuring the temperature of the first circuit Tl by the first temperature sensor and of measuring the temperature of the third circuit T3 by the third temperature sensor, said temperature of the first circuit Tl and said temperature of the third circuit T3 being transmitted to the powertrain supervisor; - a step of calculating the temperature difference ET between the temperature of the first circuit T1 and the temperature of the third circuit T3 using the following mathematical formula: ET = T1-T3; - a step of calculating the efficiency rate of the TER cooling by the cooling device using the following mathematical formula; - a step of detecting a fault in the cooling device by the powertrain supervisor when the TER cooling efficiency rate is below a predetermined threshold value for a period of time greater than a predetermined period of time.

[0009] Detecting the fault in the cooling device allows for the replacement of only this cooling device, rather than the complete replacement of the battery.

[0010] Preferably, said supervisor comprises a read-only memory, said vehicle comprising a warning means, said first circuit comprising a water pump located at the first connection, said water pump having a rotational speed, said method comprising a reconfiguration step during which the supervisor stores a fault code in said read-only memory, said warning means being activated so as to warn the driver of the fault in the cooling device, an increase in the rotation speed of the water pump controlled by said supervisor.

[0011] This alerts the user so they can promptly take the vehicle in for servicing. During servicing, the technician will be quickly informed of the cooling system fault and can replace it. Increasing the water pump speed optimizes cooling despite the cooling system malfunction.

[0012] Preferably, said method includes a recovery step during which the warning means switches off and the rotation speed of the water pump decreases when the TER cooling efficiency rate is greater than said predetermined threshold value, said recovery step being implemented after said reconfiguration step.

[0013] Thus, the vehicle owner is warned that the battery no longer presents a risk of thermal runaway.

[0014] Advantageously, said measurement step, said temperature difference calculation step and said TER cooling efficiency rate calculation step are repeated at a predefined time interval.

[0015] Advantageously, said predefined time interval is equal to 200 ms.

[0016] Advantageously, during said detection step, the predetermined time period is equal to 1 s.

[0017] Advantageously, during said detection step, the predetermined threshold value is equal to 15%.

[0018] This allows for regular monitoring to detect early the risk of thermal runaway of the battery.

[0019] The invention will be further detailed by describing non-limiting embodiments, and based on the accompanying figures illustrating variants of the invention, in which: - [Fig.l] schematically illustrates a system for monitoring the operating status of a cooling device for the heat transfer fluid of a cooling circuit in a motor vehicle when a valve is in a first position according to an embodiment of the invention; - [Fig.2] schematically illustrates the monitoring system shown in [Fig.1] when the valve is in a second position.

[0020] Figure 1 schematically illustrates a system for monitoring the operating status of a heat transfer fluid cooling device in a cooling circuit of an electric, hybrid, or fuel cell motor vehicle. The vehicle comprises a powertrain including a traction battery and a supervisor. The traction battery includes A temperature sensor. The battery can only operate within a specific temperature range, which is why monitoring its temperature using this temperature sensor is essential. The powertrain includes several control units coordinated by this supervisor, such as the battery management system, also known as the BMS (Battery Management System). The supervisor includes a management module with a valve V. This valve is configured to interact with a first circuit C1 to regulate the passenger compartment temperature, a second circuit C2 to cool the powertrain, and a third circuit C3 to regulate the temperature of the traction battery (TBM).The first circuit includes the heat transfer fluid cooling device, a heat transfer fluid heating device, an air heater, and a first temperature sensor CTL. The air heater is a heating device that operates using air as a heat transfer medium. The first temperature sensor CTI is positioned at the inlet of the first circuit C1, upstream of the cooling device, the heating device, and the air heater. The second circuit C2 includes a CVTS electrical converter, an ME electric machine, a RA radiator, and a second temperature sensor CT2 positioned at the inlet of the second circuit C2, i.e., upstream of the converter. Finally, the third circuit includes a third temperature sensor CT3 and the traction battery BDT, with the third temperature sensor CT3 positioned upstream of the traction battery BDT.Furthermore, said valve V is configured to interact with a degassing box BD. The degassing box is designed to vent gases, particularly air, that may accumulate in the cooling circuit. Valve V is configured to manage the connections between said first circuit Cl, said second circuit C2, said third circuit C3, and said degassing box BD. To this end, said valve V is capable of having a first position and a second position. The first position is characterized by the independence of the first circuit Cl from the other circuits and the degassing box BD. In other words, said first circuit Cl is connected only to said valve V and does not interact with any other component of the second circuit C2, the third circuit C3, or with said degassing box BD.In the first position, the cooling device is configured to cool only the heat transfer fluid of the first circuit C1, which is connected only to said first circuit C1. Similarly, the third circuit C3 is also independent, as it is connected only to said valve V. The second circuit C2 is independent of the first circuit C1 and the third circuit C3. However, said second circuit C2 is connected to the degassing unit via the radiator. In the first position, said heating device DC is capable of heating said heat transfer fluid of the first circuit. circuit Cl only, for the same reasons as said cooling device DR. Preferably, as illustrated in [Fig. 1], in said first position, the first circuit Cl includes a first connection C between said valve V and said first temperature sensor CTI. In addition, said first circuit Cl includes a second connection B1 between said air heater and said valve V. The second circuit C2 includes a third connection G between said valve V and said second temperature sensor CT2. Furthermore, the second circuit includes a fourth connection F between the output of the electric machine ME and said valve V and a fifth connection E between said radiator RA and said valve V. The third circuit C3 includes the sixth connection B2 between said valve V and said third temperature sensor CT3. The third circuit C3 includes a seventh connection A between said traction battery BDT and valve V.Finally, the degassing unit BD has an eighth connection D between the degassing unit and the valve V. The second position is characterized by a connection between the first circuit Cl and the third circuit C3, thus forming a circuit to which the degassing unit BD is connected. In the second position, the cooling device is therefore capable of cooling the heat transfer fluid of the first circuit Cl, the second circuit C2, and the third circuit C3. Similarly, in the second position, the heating device DC is capable of heating the heat transfer fluid of the first circuit Cl, the second circuit C2, and the third circuit C3. Preferably, as illustrated in [Fig. 2], in the second position, the seventh connection A is connected to the first connection C. The second connection B1 is connected to the sixth connection B2. The eighth connection D is connected to the first connection C.The fifth connection E is connected to the third connection G. Finally, the fourth connection F is closed. The valve V is configured to change position, moving from the first position to the second position, when the battery temperature measured by the thermal probe exceeds a predetermined threshold temperature. This is because the thermal probe is measuring a heating of the battery. Consequently, the cooling circuit is activated to attempt to lower the temperature and prevent thermal runaway of the battery. The supervisor is configured to measure the temperature difference between the temperature of the first circuit T1, measured by the first temperature sensor, and the temperature of the third circuit T3, measured by the third temperature sensor, and to calculate a cooling efficiency ratio TER to monitor the operating status of the cooling system.

[0021] Furthermore, the invention relates to a method for monitoring the operating status of the cooling device for the heat transfer fluid in the cooling circuit of said vehicle. The method is performed only when the battery The temperature of the first circuit (Tl) is higher than the predetermined threshold temperature, indicating that the cooling circuit is active. During a measurement step, the temperature of the first circuit (Tl) is measured by the first temperature sensor (CTI), and the temperature of the third circuit (T3) is measured by the third temperature sensor (CT3). The temperatures of the first circuit (Tl) and the third circuit (T3) are then transmitted to the powertrain supervisor for processing. Preferably, this measurement step is repeated at a predefined time interval, for example, 200 ms. During a temperature deviation calculation step (ET), the temperature deviation (ET) is calculated using the following mathematical formula: ET = Tl - T3.During a step in calculating the TER cooling efficiency ratio, the TER cooling efficiency ratio, which measures the performance of the DR cooling device, is calculated using the following mathematical formula: TfiR — . During a detection step, we . A fault in the DR cooling system is considered to be detected when the TER cooling efficiency rate is below a predetermined threshold value for a period exceeding a predetermined time period. Preferably, the predetermined time period is 1 second. Preferably, the predetermined threshold value is 15%. Optionally, the supervisor includes read-only memory, and the first circuit C1 includes a water pump with a rotational speed. The water pump is located at the first connection C. Furthermore, the vehicle includes a warning means. For example, a warning means is an indicator light on a dashboard or a buzzer. The method then includes an optional reconfiguration step.During the reconfiguration step, the supervisor stores a fault code in read-only memory (ROM) so that a technician can identify the fault as originating from the cooling system, thus avoiding a complete battery replacement. Additionally, a warning system is activated to inform the driver that the DR cooling system has a fault and that vehicle servicing is required. Finally, the water pump speed is increased to enhance battery cooling despite the DR cooling system fault. This increase in pump speed is controlled by the supervisor. Preferably, a recovery step is implemented following the reconfiguration step.The recovery stage is characterized by the extinction of the warning means and a decrease in the rotation speed of the water pump when the cooling efficiency rate TER is greater than said predetermined threshold value.

Claims

1. Demands A system for monitoring the operating status of a cooling device for the heat transfer fluid of a cooling circuit of an electric, hybrid or fuel cell motor vehicle, said vehicle comprising a powertrain including a traction battery (TB) and a supervisor, said traction battery comprising a thermal probe, said supervisor comprising a management module (MG), characterized in that said management module (MG) comprising a valve (V) configured to interact with a degassing box, a first circuit for regulating the temperature of the passenger compartment, a second circuit for cooling said powertrain and a third circuit for regulating the temperature of said traction battery (TB), said first circuit comprising the cooling device, a heating device, a heater and a first temperature sensor (CTI),the second circuit comprising an electrical converter (CVTS), an electric machine (ME), a radiator (RA) and a second temperature sensor (CT2), said third circuit comprising a third temperature sensor (CT3) and said traction battery (BDT), said valve (V) being configured to manage the connections between said first circuit, said second circuit, said third circuit and said degassing box, said valve (V) being capable of having two positions:, - a first position in which the first circuit is independent of the second circuit, the third circuit and the degassing box, the second circuit being independent of the first circuit and the third circuit, said second circuit being connected to the degassing box via the radiator (RA), the third circuit being independent of the first circuit, the second circuit and the degassing box, said cooling device being configured to cool the heat transfer fluid of the first circuit, said heating device being configured to heat the heat transfer fluid of the first circuit; - a second position in which the first circuit is connected to the third circuit, the degassing unit being connected to the circuit formed by the first and third circuits, said device cooling being configured to cool the heat transfer fluid of the first circuit, the second circuit and the third circuit, said heating device being configured to heat the heat transfer fluid of the first circuit and the third circuit; said valve moving from the first position to the second position when the temperature of the coil measured by said thermal probe is above a predetermined threshold temperature, said supervisor being configured to measure a temperature difference between a temperature of the first circuit T1 from the first temperature sensor and a temperature of the third circuit T3 from the third temperature sensor and to calculate a cooling efficiency ratio TER to monitor the operating status of said cooling device.

2. System according to claim 1 characterized in that, in the first position, the first circuit comprises a first connection (C) between said valve (V) and said first temperature sensor (CTI) and a second connection (B1) between said air heater and said valve (V), said second circuit comprising a third connection (G) between said valve (V) and said second temperature sensor (CT2), a fourth connection (F) between the output of the electric machine (ME) and said valve (V) and a fifth connection (E) between said radiator (RA) and said valve (V), the third circuit comprising a sixth connection (B2) between said valve (V) and said third temperature sensor (CT3) and a seventh connection (A) between said traction battery and the valve (V), said degassing box comprising an eighth connection (D) between said degassing box and said valve (V), and, in the second position,the seventh connection (A) being connected to the first connection (C), the second connection (B1) being connected to the sixth connection (B2), the eighth connection (D) being connected to the first connection (C), the fifth connection (E) being connected to the third connection (G), the said fourth connection (F) being closed.

3. Method for monitoring the operating status of a cooling device for the heat transfer fluid of a cooling circuit in an electric, hybrid, or fuel cell motor vehicle, by means of a system for monitoring the operating status of a cooling device according to the claim 1 or 2, said battery having a temperature above said predetermined threshold temperature, characterized in that said method comprises the following steps: - a step of measuring the temperature of the first circuit T1 by the first temperature sensor (CTI) and of measuring the temperature of the third circuit T3 by the third temperature sensor (CT3), said temperature of the first circuit T1 and said temperature of the third circuit T3 being transmitted to the powertrain supervisor; - a step of calculating the temperature difference ET between the temperature of the first circuit T1 and the temperature of the third circuit T3 by the following mathematical formula: ET = T1-T3; - a step of calculating the cooling efficiency rate TER by the cooling device by the following mathematical formula: TER —;- a step for the powertrain supervisor to detect a fault in the cooling system when the cooling efficiency ratio (TER) is below a predetermined threshold value for a period of time exceeding a predetermined period of time.

4. Method according to claim 3 characterized in that said supervisor comprises a read-only memory, said vehicle comprising a warning means, said first circuit comprising a water pump located at the first connection (C), said water pump having a rotation speed, said method comprising a reconfiguration step during which the supervisor stores a fault code in said read-only memory, said warning means is activated so as to warn the driver of the fault in the cooling device, an increase in the rotation speed of the water pump controlled by said supervisor.

5. A method according to claim 4 characterized in that said method comprises a recovery step during which the warning means switches off and the rotation speed of the water pump decreases when the cooling efficiency ratio TER is greater than said predetermined threshold value, said recovery step being implemented after said reconfiguration step.

6. A method according to any one of claims 3 to 5 characterized in that said measurement step, said temperature difference calculation step and said TER cooling efficiency rate calculation step are repeated at a predefined time interval.

7. Method according to claim 6 characterized in that said predefined time interval is equal to 200 ms.

8. A method according to any one of claims 3 to 7 characterized in that, during said detection step, the predetermined time period is equal to 1 s.

9. A method according to any one of claims 3 to 8 characterized in that, during said detection step, the predetermined threshold value is equal to 15%.