Description:Complete specification: The following specification particularly describes the invention and the manner in which it is to be performed.

Field of the invention:
[0001] The present disclosure relates to an electronic control unit (ECU), and particularly to an ECU to detect an anomaly in a coolant system of a vehicle.

Background of the invention:
[0002] The coolant system of an automobile/vehicle manages the engine temperature and makes sure the engine does not overheat during its operation. The coolant system to maintain the engine temperature at an optimal level majorly makes use of a coolant, a coolant circuit, a radiator, and a radiator fan. The coolant flows through the coolant circuit and takes away the heat from the engine. This coolant then flows through the radiator where it loses the heat and returns to a cooler temperature. The radiator fan pulls the cooling air into the radiator enhancing the cooling of the coolant. The coolant system also makes use of a coolant level sensor to detect presence/absence of the coolant. The coolant level sensor helps ensuring the proper operation of the coolant system.

[0003] The coolant system at time runs into an anomaly. Some of the common anomalies are low coolant level and blockage in the coolant circuit. The detection of these anomalies requires sensors and specifically the coolant level sensor. However, there doesn’t exist any reliable mechanism to detect these anomalies without the use of the coolant level sensor.

[0004] US2016186650 AA discloses a methods and systems for improving engine coolant level estimation to reduce engine overheating. The level of fluid in a coolant overflow reservoir is inferred based on the fluid level in a hollow vertical standpipe fluidically coupled to the reservoir at top and bottom locations, while the fluid level in the standpipe is estimated based on output from an ultrasonic signal transmitted by a sensor positioned in a recess at the bottom of the vertical standpipe. Sensor power usage is optimized based on the ratio of first order and higher order harmonic echo times in the raw data set generated by the sensor.

[0005] The present invention solves all the above-mentioned problems in a manner as described in the claims.

Brief description of the accompanying drawings:
[0006] An embodiment of the disclosure is described with reference to the following accompanying drawings.
[0007] Fig. 1 illustrates block diagram of a vehicle with an electronic control unit (ECU) to detect an anomaly in a coolant system, according to an embodiment of the present invention;
[0008] Fig. 2 illustrates pictorial representation of difference between the expected waveform and the actual waveform of a radiator fan operation during the anomaly, according to an embodiment of the present invention; and
[0009] Fig. 3 illustrates flow diagram of a method for detecting the anomaly in the coolant system of the vehicle, according to the present invention.

Detailed description of the embodiments:
[0010] Fig. 1 illustrates block diagram of a vehicle with an electronic control unit (ECU) to detect an anomaly in a coolant system, according to an embodiment of the present invention. The coolant system 104 comprises a radiator fan 108. The ECU 102 is configured to, characterized in that, calculate at least one of an operation duration of the radiator fan 108 and an operation frequency of the radiator fan 108, receive vehicle parameters from respective sensors 106 within the vehicle 100, and detect the anomaly based on the vehicle parameters and at least one of the operation duration of the radiator fan 108 and the operation frequency of the radiator fan 108. The detected anomaly is at least one of low coolant level and blockage in a coolant circuit of the coolant system 104. The detection of the mentioned anomaly is done without making use of a coolant level sensor in the automobile/vehicle 100.

[0011] The ECU 102 controls the radiator fan 108 operation for cooling a coolant, of the coolant system 104, flowing through an engine of the automobile/vehicle 100. The ECU 102 switches ON the radiator fan 108 whenever the coolant temperature rises above a predetermined temperature. The ECU 102 fetches details of the radiator fan 108 operation to calculate at least one of the operation duration of the radiator fan 108 and the operation frequency of the radiator fan 108.

[0012] In an embodiment of the present invention, the vehicle parameters is selected from a group comprising vehicle speed, engine temperature, ambient temperature and operating load of the engine of the vehicle 100. The vehicle parameters are received from the respective sensors 106 present within the vehicle 100. The respective sensors 106 are not listed out due to being known in the art, however the same must not be understood in a limiting manner. The ECU 102 calculates an expected duration of the radiator fan 108 operation for a single fan cycle using the vehicle parameters. The single fan cycle is the period for which the radiator fan 108 is switched ON for enhanced cooling of the coolant. The ECU 102 also calculates an expected frequency of the radiator fan 108 operation for a predetermined period using the vehicle parameters. The predetermined period for which the expected frequency of the radiator fan 108 operation is calculated is selected based on the vehicle 100 operating conditions and other conditions. In an embodiment of the present invention, the predetermined period is five minutes.

[0013] In an embodiment of the present invention, the ECU 102 detects anomaly based on at least one of the operation duration of the radiator fan 108 and the operation frequency of the radiator fan 108 and at least one of the expected duration of the radiator fan 108 operation for the single fan cycle and the expected frequency of the radiator fan 108 operation for the predetermined period. In another embodiment of the present invention, the ECU 102 compares at least one of the operation duration of the radiator fan 108 with the expected duration of the radiator fan 108 operation and the operation frequency of the radiator fan 108 with the expected frequency of the radiator fan 108 operation to detect anomaly. The ECU 102 detects anomaly if the operation duration of the radiator fan 108 is greater than or equal to three times of the expected duration of the radiator fan 108 operation. The ECU 102 detects anomaly if the operation frequency of the radiator fan 108 is greater than three times of the expected frequency of the radiator fan 108 operation.

[0014] The ECU 102 after detecting the anomaly, raises an alarm/light/symbol on the Human machine interface (HMI) of the automobile/vehicle 100. In an embodiment of the present invention, the vehicle 100 is selected from a group comprising a two-wheeler, a three-wheeler, a four-wheeler, and a multi-wheel vehicle comprising the radiator fan 108 in the coolant system 104. Whenever the driver becomes aware of the detected anomaly, he can either physically inspect for the low coolant level or take the vehicle 100 for inspection to a service center.

[0015] The ECU 102 calculates the expected duration of the radiator fan 108 operation and the expected frequency of the radiator fan 108 operation using the vehicle parameters. The expected duration of the radiator fan 108 operation is a function of vehicle speed, engine temperature, ambient temperature and operating load of the engine of the vehicle 100. Similarly, the expected frequency of the radiator fan 108 operation is a function of vehicle speed, engine temperature, ambient temperature and operating load of the engine of the vehicle 100.

C = f (v, e, a, l) = f(v1*e1*a1*l1)
D = f (v, e, a, l) = f(v1*e1*a1*l1)
C- The expected duration of the radiator fan 108 operation for the single fan cycle
D- The expected frequency of the radiator fan 108 operation for the predetermined period
v- vehicle speed
e- engine temperature
a- ambient temperature
l- operating load of the engine of the vehicle 100
v1- factor1*v
e1- factor2*e
a1- factor3*a
l1- factor4*l
*- multiplication

[0016] In an embodiment of the present invention, the factors: factor1, factor2, factor3, factor4 mentioned above are utilized to calculate C and D in real-time. The values of the factors: factor1, factor2, factor3, factor4 are selected based on the vehicle 100 operating conditions and other conditions. C represents the expected duration of the radiator fan 108 operation for the single fan cycle and D represents the expected frequency of the radiator fan 108 operation for the predetermined period. The v, e, a, l represent vehicle speed, engine temperature, ambient temperature and operating load of the engine of the vehicle 100 respectively. The v1, e1, a1, l1 are calculated by multiplying factor1 with v, factor2 with e, factor3 with a and factor4 with l respectively.

v(km/h) 10 30 50 70 90 110 130
v1 2.3 2.1 1.9 1.7 1.5 1.3 1
e(°C) 10 30 50 70 90 110 130
e1 1 1.3 1.5 1.7 1.9 2.1 2.3
a(°C) 10 30 50 70 90 110 130
a1 1 1.3 1.5 1.7 1.9 2.1 2.3
l(%) 10 20 30 50 70 80 100
l1 1 1.3 1.5 1.7 1.9 2.1 2.3
v1*e1*a1*l1 1 5 7 10 15 20 30
C (sec) 10 15 20 25 30 40 60
D 1 3 5 7 9 11 13

[0017] For an embodiment of the present invention, the above table represents the empirical values of v, e, a, l, v1, e1, a1, l1, C and D recorded during the vehicle 100 operation. It is observable from the table that the values of e1 and a1 increases with the increase in the values of engine temperature (e) and ambient temperature (a) respectively because of the enhanced cooling requirement due to higher temperatures. Similarly with increase in value of the operating load of the engine (l) the value of l1 increases because of the enhanced cooling requirement as more heat is being generated in the engine. Whereas the value of the v1 decreases with increase in the value of vehicle speed (v) because higher speeds ensure enhanced air flow of cooler air in the radiator and the surroundings of the engine of the vehicle 100.

[0018] Fig. 2 illustrates pictorial representation of difference between the expected waveform and the actual waveform of a radiator fan operation during the anomaly, according to an embodiment of the present invention. A waveform A represents the expected waveform of the radiator fan operation 108 calculated based on the vehicle parameters. The duration of each pulse in the waveform A represents the expected duration of the radiator fan 108 operation for the single fan cycle calculated by the ECU 102 using the vehicle parameters. The number of pulses in the waveform A represents the expected frequency of the radiator fan 108 operation for a predetermined period calculated by the ECU 102 using the vehicle parameters. A waveform B represents the waveform of the radiator fan 108 actual operation calculated by the ECU 102 for the same predetermined period.

[0019] The horizontal axis of the waveform A and the waveform B represent time. Whereas, the vertical axis of the waveform A and the waveform B represents the status, switched ON/OFF, of the radiator fan 108. Each pulse in the waveform A and the waveform B represents the frequency of the operation of the radiator fan 108 whereas the width of each pulse represents the duration of the radiator fan 108 operation for that single fan cycle. Both waveforms are calculated by the ECU 102 for the same predetermined period. It is evident from the Fig. 2 that the frequency and/or duration of the radiator fan 108 operation will increase whenever any anomaly occurs leading to improper engine cooling.

[0020] Fig. 3 illustrates flow diagram of a method for detecting the anomaly in the coolant system of the vehicle, according to the present invention. The coolant system 104 comprises the radiator fan 108. The method for detecting the anomaly in the coolant system 104 comprises a plurality of steps some of which are illustrated in Fig. 3 using blocks 302 to 306, according to the present invention. The step 302 comprises calculating at least one of the operation duration of the radiator fan 108 and the operation frequency of the radiator fan 108. The calculation of the operation duration and the operation frequency of the radiator fan 108 is done in real-time by the ECU 102.

[0021] A step 304 comprises receiving the vehicle parameters from the respective sensors 106 present within the vehicle 100. The step 306 comprises detecting the anomaly based on the vehicle parameters and at least one of the operation duration of the radiator fan 108 and the operation frequency of the radiator fan 108.

[0022] According to the method, for detecting the anomaly the method comprises calculating at least one of the expected duration of the radiator fan 108 operation for the single fan cycle and the expected frequency of the radiator fan 108 operation for the predetermined period using the vehicle parameters. The predetermined period for which the expected frequency of the radiator fan 108 operation is calculated is selected based on the vehicle 100 operating conditions and other conditions. In an embodiment of the present invention, the predetermined period is five minutes.

[0023] According to the method, the anomaly is detected by comparing at least one of the operation duration of the radiator fan 108 with the expected duration of the radiator fan 108 operation and the operation frequency of the radiator fan 108 with the expected frequency of the radiator fan 108 operation. The method detects the anomaly if the operation duration of the radiator fan 108 is greater than or equal to three times of the expected duration of the radiator fan 108 operation. The method detects the anomaly if the operation frequency of the radiator fan 108 is greater than three times of the expected frequency of the radiator fan 108 operation.

[0024] According to the present invention, the ECU 102 to detect the anomaly in the coolant system 104 of the vehicle 100 is disclosed. The present invention solves the problems discussed above. The present invention provides a reliable mechanism to detect the anomaly in the coolant system 104 without using the coolant level sensor. The present invention provides a cost benefit of being implemented in the automobile/vehicle 100 not having the coolant level sensor. Also, the present invention provides an additional means to detect the anomaly in the automobile/vehicle 100 where the coolant level sensor is present as a redundancy. The anomaly detection mechanism disclosed above can also be used when the coolant level sensor is not working properly.

[0025] It should be understood that the embodiments explained in the description above are only illustrative and do not limit the scope of this invention. Many such embodiments and other modification and changes in the embodiment explained in the description are envisaged. The scope of the invention is only limited by the scope of the claims.
, Claims:We claim:

1. An electronic control unit (ECU) (102) to detect an anomaly in a coolant system (104) of a vehicle (100), said coolant system (104) comprises a radiator fan (108), said ECU (102) configured to, characterized in that,
? Calculate at least one of an operation duration of said radiator fan (108) and an operation frequency of said radiator fan (108);
? Receive vehicle parameters from respective sensors (106) within said vehicle (100); and
? Detect said anomaly based on said vehicle parameters and at least one of said operation duration of said radiator fan (108) and said operation frequency of said radiator fan (108).

2. The ECU (102) as claimed in claim 1, wherein said anomaly is at least one of low coolant level and blockage in a coolant circuit of said coolant system (104).

3. The ECU (102) as claimed in claim 1, wherein said vehicle parameters is selected from a group comprising vehicle speed, engine temperature, ambient temperature and operating load of an engine of said vehicle (100).

4. The ECU (102) as claimed in claim 1, wherein said ECU (102) calculates an expected duration of said radiator fan (108) operation for a single fan cycle and an expected frequency of said radiator fan (108) operation for a predetermined period using said vehicle parameters.

5. The ECU (102) as claimed in claim 4, wherein said ECU (102) compares at least one of said operation duration of said radiator fan (108) with said expected duration of said radiator fan (108) operation and said operation frequency of said radiator fan (108) with said expected frequency of said radiator fan (108) operation to detect said anomaly.

6. The ECU (102) as claimed in claim 1, wherein said vehicle (100) is selected from a group comprising a two-wheeler, a three-wheeler, a four-wheeler, and a multi-wheel vehicle.

7. A method for detecting an anomaly in a coolant system (104) of a vehicle (100), said coolant system (104) comprises a radiator fan (108), characterized by, said method comprising the steps of,
? Calculating at least one of an operation duration of said radiator fan (108) and an operation frequency of said radiator fan (108);
? Receiving vehicle parameters from respective sensors (106) within said vehicle (100); and
? Detecting said anomaly based on said vehicle parameters and at least one of said operation duration of said radiator fan (108) and said operation frequency of said radiator fan (108).

8. The method as claimed in claim 7, wherein said method for detecting said anomaly comprises calculating at least one of said expected duration of said radiator fan (108) operation for said single fan cycle and said expected frequency of said radiator fan (108) operation for said predetermined period using said vehicle parameters.

9. The method as claimed in claim 8, wherein said anomaly is detected by comparing at least one of said operation duration of said radiator fan (108) with said expected duration of said radiator fan (108) operation and said operation frequency of said radiator fan (108) with said expected frequency of said radiator fan (108) operation.