JP2020105926A - Fuel residual amount calculation device of vehicle - Google Patents

Abstract

To calculate a fuel residual amount which is high in accuracy, in a fuel residual amount calculation device of a vehicle.SOLUTION: Consumed fuel acquired from an injector valve-opening time is subtracted from a fuel amount at fuel supply, and a final fuel residual amount is calculated by using a calculated fuel residual amount (B) and a fuel residual amount (A) which is calculated on the basis of an input from a fuel sender for detecting a level height of a fuel tank. At this time, when a difference between a short-time average value (A) of a sender value and the fuel residual amount (A) is equal to a prescribed value (L1) or larger, and this state continues for a prescribed time (T4) or longer, it is determined that the fuel residual amount (A) is deviated, the deviation is counted as a deviation time (T5) up until a magnitude relationship between the short-time average value (A) and the fuel residual amount (A) is inverted, a time which is substantially the same as the deviation time (T5) is set as a correction prohibition time (T6), and by prohibiting a correction for making the fuel residual amount (B) approximate the fuel residual amount (A) during the setting while avoiding an erroneous correction as much as possible, an accurate calculation of the fuel residual amount is thereby performed.SELECTED DRAWING: Figure 5

Description

The present invention relates to a remaining fuel amount calculating device for a vehicle.

When displaying the remaining fuel level of an automobile, the fuel consumption is calculated from the sender method (1), which detects the liquid level by a float fuel sender installed in the fuel tank, and the fuel injection device (injector) valve open time. An injector method (2) is known in which the consumed fuel is subtracted from the current fuel to calculate the remaining fuel amount.

FIG. 7 is a diagram showing the remaining fuel amount calculated by the calculation based on the sender value by the sender method (1). As shown in the figure, the remaining fuel amount A is calculated as follows based on the short-time average value A calculated from the sender value (for example, the average value of about 3 seconds).
That is, when the remaining fuel amount A>the short-time average value A, the predetermined amount Ka is subtracted from the previous remaining fuel amount A to calculate the present remaining fuel amount A.
Remaining fuel amount A(n) = Remaining fuel amount A(n-1)-Ka... (1)
When the remaining fuel amount A<the short-time average value A, the remaining fuel amount A is calculated by adding a predetermined amount Ka to the remaining fuel amount A. Ka may be a value proportional to the difference between the remaining fuel amount A and the short-term average value A.
Remaining fuel amount A(n)=remaining fuel amount A(n-1)+Ka...(2)

The fuel remaining amount A calculated by this sender method (1) uses the fuel sender input, so when the vehicle approaches an inclination, the actual fuel remaining amount A ( There is a drawback that it will be greatly different from the actual remaining amount).

FIG. 8 is a diagram showing the remaining fuel amount based on the fuel consumption amount calculated from the valve opening time of the injector by the injector system (2). In this injector system (2), the remaining fuel amount is calculated as follows.
Remaining fuel amount B(n) = Remaining fuel amount B(n-1)-Fuel consumption integrated value (3)
However, the remaining fuel amount B calculated by the injector method (2) uses the fuel consumption amount, so that it is not affected by the slope as in the sender method (1) shown in FIG. The deviation of the initial value of the amount and the accumulated error may be accumulated, and the deviation from the actual remaining amount may occur.

Therefore, the following correction method (4), in which the injector method (2) is further modified so as to gradually approach the remaining fuel amount A based on the sender value, is also conceivable.
Remaining fuel amount B(n)=remaining fuel amount B(n-1)-integrated fuel consumption value+K (K: correction value) (4)
In the correction method (4), the correction value K is set according to the difference between the remaining fuel amount B and the remaining fuel amount A calculated from the sender value. When the remaining fuel amount B is larger than the remaining fuel amount A, K<0 is subtracted. When the remaining fuel amount B is smaller than the remaining fuel amount A, K>0 is added. In FIG. 8, the remaining fuel amount B with correction shown by the thick solid line is obtained. However, in this case, as in the case of the sender method (1) in FIG. 7, it is affected by the slope.

In Patent Document 1, as in the injector system (2) shown in FIG. 8, the fuel consumption is calculated from the valve opening time of the injector, the fuel consumption is subtracted from the fuel amount at the time of refueling, and the fuel remaining amount is displayed. A remaining amount calculation device is disclosed. In this patent document 1, in consideration of the fact that the remaining amount becomes inaccurate due to the manufacturing error of the fuel injection device, the correction of the remaining amount display when the liquid level of the fuel tank becomes a preset liquid level height I'm trying to do.

JP-A-58-122433

However, in the technique of Patent Document 1, the correction is performed only at the preset liquid level height, and in other states, the error from the actual remaining amount may be large. Further, when the vehicle travels on a sloped road or a curve, the fuel liquid level changes, and the short-time average value A calculated based on the sender value immediately reflects the change. If the situation continues, the remaining fuel amount A obtained by filtering the sender value gradually follows the short-term average value A and deviates from the actual remaining amount.

Therefore, when a correction condition is set so that the remaining fuel amount can be corrected while the vehicle is traveling, and it is determined that the correction condition is satisfied and the liquid level in the fuel tank is stable, the remaining fuel amount B is set to the remaining fuel amount A. It is only necessary to make a correction so that the liquid level is close to each other, but even if the above-mentioned correction condition is satisfied, the liquid surface is not always stable, and the judgment becomes very difficult.

In particular, in the process in which the vehicle returns from the sloping road to the flat road and the remaining fuel amount A follows the short-term average value A (=actual remaining amount), the difference between the remaining fuel amount A and the short-term average value A is a predetermined value. Although there is a section as below, at this time, there is a possibility that the fuel remaining amount A may be erroneously corrected on the assumption that the correction condition is satisfied even though the remaining fuel amount A has not returned to the actual remaining amount.

In view of the above, the present invention is based on the remaining fuel amount calculated from the consumed fuel, and when the remaining fuel amount detected from the liquid level height of the fuel tank is appropriate, the fuel remaining amount detected from the liquid level height is used. It is an object of the present invention to provide a vehicle fuel remaining amount calculation apparatus capable of performing correction to bring the correction closer to each other and setting a correction prohibition condition for prohibiting such correction, and calculating (displaying) the fuel remaining amount with high accuracy.

In order to achieve the above object, in a preferred embodiment of the present invention, the fuel remaining amount B calculated by subtracting the consumed fuel calculated from the injector valve opening time from the fuel amount at the time of refueling, and the liquid in the fuel tank. In a fuel remaining amount calculation device for a vehicle having a control unit for calculating a final fuel remaining amount using a fuel remaining amount A smoothed by a filter calculation based on an input from a fuel sender for detecting a surface height. The controller controls the first predetermined time T1 (e.g. If it continues for more than a minute), it is determined that there is a deviation in the remaining fuel amount B and correction is necessary, and the correction is performed to bring the remaining fuel amount B closer to the remaining fuel amount A.

However, the control unit determines that the difference between the short-term average value A of the fuel sender input and the fuel remaining amount A is a second predetermined value L1 (for example, 1 liter (L)) or more, and the state is the second. When it continues for a predetermined time T4 (for example, 120 seconds) or more, it is determined as the deviation of the remaining fuel amount A, the deviation time T5 is continuously counted including the second predetermined time T4, and the short-time average value A is obtained. When the magnitude relationship with the remaining fuel amount A is reversed, or during the counting, the short-time average value A and the remaining fuel amount A are below a third predetermined value L2 (for example, 0.5 liter (L)). At this time, the counting of the deviation time T5 is stopped, and the remaining fuel amount B is set to the correction prohibition time T6 which is equal to or longer than the deviation time T5 by a predetermined time α (for example, 60 seconds). Prohibition of correction to approach the remaining fuel amount A.

According to the present invention, based on the remaining fuel amount B calculated from the consumed fuel, only when the remaining fuel amount detected from the liquid level of the fuel tank is appropriate, the remaining fuel amount calculated from the consumed fuel is set to the liquid level height. The correction is performed to bring the detected fuel remaining amount closer to the detected fuel remaining amount. At this time, the difference between the short-time average value A and the fuel remaining amount A is the second predetermined value L1 or more, and the state is the second predetermined time T4 or more. When it continues, it is determined that there is a deviation of the remaining fuel amount A, and the deviation time T5 is continuously counted, and the magnitude relationship between the short-term average value A and the remaining fuel amount A is reversed (reversed) or more than a predetermined value. When it is small, the counting of the deviation time T5 is stopped, and the correction prohibiting time T6 is set to be substantially the same time as the deviation time T5, so that the correction of bringing the remaining fuel amount B close to the remaining fuel amount A is prohibited. It is possible to avoid the correction as much as possible and calculate the remaining fuel amount with high accuracy.

FIG. 3 is a control block diagram of a vehicle fuel remaining amount calculation apparatus that is an embodiment of the present invention. It is a figure showing the fuel residual quantity at the time of calculating a fuel residual quantity similarly using the fuel residual quantity calculation device of this embodiment. It is a figure which shows the remaining fuel amount which changes with time, and its correction|amendment prohibition condition. It is a figure showing the calculation state of the amount of remaining fuel at the time of high speed running of a vehicle over time. It is a figure which extracts and expands and represents a one part area of FIG. It is a calculation flowchart of the remaining fuel amount. It is a figure which shows the fuel residual amount calculated by the calculation based on the conventional fuel sender input value. It is a figure which shows the fuel residual amount calculated by the calculation of the conventional fuel consumption amount base.

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a vehicle fuel remaining amount calculation apparatus 1 according to the present embodiment includes a vehicle speed sensor 3 on the input side of an electronic control unit (ECU) of a vehicle, which is a control unit 2, and a vehicle speed sensor 3 for detecting the vehicle speed. A float-type fuel sender 4 that detects the remaining amount of fuel from the liquid level in the fuel tank, and a fuel consumption amount detection unit 5 that outputs the fuel consumption amount obtained from the valve opening time of the injector (fuel injection device) are provided. It is connected.

In the control unit 2, the fuel remaining amount B calculated by subtracting the consumed fuel obtained from the injector opening time from the fuel amount at the time of refueling, and the fuel remaining amount calculated by the fuel sender 4 from the liquid level of the fuel tank. The final remaining fuel amount is calculated using A and. In the control unit 2, the remaining fuel amount detected from the liquid level of the fuel sender 4 is input to the remaining fuel amount calculation unit 8 via the short-time average value 7, and the consumed fuel amount obtained from the valve opening time of the injector is input. The amount is integrated by the integration unit 9, and the remaining fuel amount calculation unit 8 calculates as follows.

That is, in the fuel remaining amount calculation unit 8 of the control unit 2, the difference between the fuel remaining amount B calculated from the consumed fuel and the fuel remaining amount A calculated from the fuel sender input is the first predetermined value C1 (for example, 3L) or more. When the above state continues for the first predetermined time T1 (for example, 5 minutes) or more, it is determined that there is a deviation in the remaining fuel amount B calculated from the consumed fuel and correction is necessary.

However, the control unit 2 determines that the difference between the short-term average value A based on the sender value and the remaining fuel amount A is the second predetermined value L1 (for example, ±3 liters) or more, and the state is the second predetermined time T4. When the above is continued, it is determined that the difference in the remaining fuel amount A, the counting of the difference time T5 including the second predetermined time T4 is continued, and the magnitude relationship between the short time average value A and the remaining fuel amount A is determined. Is reversed, or when the short-time average value A and the remaining fuel amount A become equal to or less than a third predetermined value (for example, 0.5 liter) during the counting, the counting of the deviation time T5 is stopped, and A correction prohibiting time T6 is equal to or longer than the deviation time T5 or a predetermined time α (for example, 60 seconds) longer than the deviation time T5, and the correction of bringing the remaining fuel amount B close to the remaining fuel amount A is prohibited.

The control unit 2 also sets the following correction conditions in addition to the correction prohibition conditions. That is, the control unit 2 determines that the difference between the average value A of the fuel sender input for a short time (for example, 3 seconds) and the remaining fuel amount A calculated from the fuel sender input is a predetermined value C2 (for example, 1 L) or less, and the state is predetermined. When it continues for time T2 or more (for example, 12 seconds or more), it is determined that the liquid level in the fuel tank is stable, the fuel remaining amount A calculated from the fuel sender input is correct, and the fuel consumption is calculated. The correction is performed to bring the remaining fuel amount B closer to the remaining fuel amount A calculated from the fuel sender input.

Further, in the control unit 2, when the vehicle speed input from the vehicle speed sensor 3 is a predetermined value V1 (for example, 20 km/h) or more, the fuel remaining amount B calculated from the consumed fuel is changed to the fuel remaining amount calculated from the fuel sender input. A correction is made to bring it closer to A. This takes into consideration that the short-term average value A and the remaining fuel amount A coincide with each other over time when the vehicle speed decreases on a long uphill road or a curve.

When all the conditions such as the above-described correction prohibition condition are satisfied, the control unit 2 corrects the remaining fuel amount B calculated from the consumed fuel to approach the remaining fuel amount A calculated from the fuel sender input.

However, in the control unit 2, the fuel remaining amount A calculated from the fuel sender input is a predetermined value C0 or less (for example, 10 liters or less), and the fuel remaining amount B calculated from the consumed fuel is the fuel calculated from the fuel sender input. If the remaining amount A is larger than the remaining amount A, there is a risk of running out of fuel (gas shortage). Therefore, regardless of the vehicle speed, a correction is made to bring the remaining fuel amount B calculated from the consumed fuel closer to the remaining fuel amount A calculated from the fuel sender input. I am trying to do it.

Then, on the output side of the control unit 2, the remaining fuel amount value calculated by the remaining fuel amount calculation unit 8 is displayed on the remaining fuel amount display unit 6 such as a liquid crystal display provided on the instrument panel in the vehicle compartment. It is connected.

FIG. 2 is a graph showing the remaining amount of fuel in the fuel tank in this embodiment on the time axis (horizontal axis). The short-time average value (for example, about 3 seconds) calculated from the fuel sender input value is defined as the short-time average value A, and the remaining fuel amount filtered so as to be sufficiently smooth is referred to as "remaining fuel amount A". .. The remaining fuel amount calculated based on the integrated fuel consumption value is referred to as "remaining fuel amount B".
Remaining fuel amount B(n) = Remaining fuel amount B(n-1)-Fuel consumption integrated value + K (K: correction value) ··· (4)

FIG. 2 is a diagram showing the state of calculation when calculating the remaining fuel amount with time. In FIG. 2, a fine dotted line B-2 shows the uncorrected fuel remaining amount B, and a solid line B-1 shows the corrected remaining fuel amount B, respectively. Further, the rough dotted line A-2 indicates the remaining fuel amount A calculated from the fuel sender input, and the stepwise thin line A-1 indicates the short-time average value A (the short-time average value from the fuel sender input value: for example, about 3 seconds). The average value) is shown.

At the time of M1 in FIG. 2, there is a difference between the remaining fuel amount A and the remaining fuel amount B-1, and there is no difference between the short-time average value A and the remaining fuel amount A. At the time of M1, it is assumed that the liquid level in the fuel tank is stable, and the remaining fuel amount B-1 is corrected toward the remaining fuel amount A-2. In short, the fuel sender value detected from the liquid level in the fuel tank is corrected.

At M2 in FIG. 2, if there is a large difference between the short-term average value A and the remaining fuel amount A, the remaining fuel amount B-1 is not corrected. That is, the sender value detected from the liquid level in the fuel tank cannot be trusted. Further, at M3 in FIG. 2, the difference between the remaining fuel amount B-1 and the remaining fuel amount A is small. In this case also, there is no need for correction, so no correction is made.

FIG. 3 is a diagram conceptually showing the short-term average value A and the remaining fuel amount A that change depending on the traveling environment of the vehicle (whether traveling on a slope or on a flat surface). Section I shows traveling on a flat road. In this section I, the remaining fuel amount A gradually converges to the short-term average value A. Section II shows driving on a slope. In this section II, the short-term average value A changes greatly with the inclination. The remaining fuel amount A calculated from the sender value follows the short-term average value A and deviates from the actual remaining amount. Section III shows running back on a flat road. In this section III, the short-time average value A returns to the original remaining amount. The remaining fuel amount A also follows the short-term average value A and returns to the actual remaining amount.

In FIG. 3, at point X, the short-time average value A and the remaining fuel amount A continue to deviate in the same direction, and the liquid surface inclination determination is established. At point Y, the relationship between the short-term average value A and the remaining fuel amount A is reversed (the sign of the deviation is reversed), and the liquid surface inclination determination is completed. In the present embodiment, when the difference between the short-time average value A and the remaining fuel amount A is a predetermined value L1 (for example, ±3 liters) or more and the state continues for a predetermined time T4 (for example, 120 seconds) or more, the fuel is It is determined that the remaining amount A deviates, and the deviation time T5 is continuously counted including the predetermined time T4. When the short-time average value A and the remaining fuel amount A are reversed (reversed), the deviation time T5 is stopped, and then the correction prohibition time T6 is set.

The correction inhibition time T6 can be set by T6=deviation time T5+predetermined time α. The predetermined time α is, eg, 60 seconds. That is, the correction inhibition time T6 is set to be substantially the same as the deviation time T5. At point Z, the difference between the short-term average value A and the remaining fuel amount A becomes small, and it is erroneously established that the liquid surface is stable. For example, this is a situation where the correction condition C shown in FIG. 6 is satisfied (S11:Y).

In the present embodiment, the correction of the remaining amount of fuel is prohibited because it is within the correction prohibited time even in the situation of the point Z. Here, the correction prohibition time T6 is based on the idea that the stability of the liquid surface is established by ensuring a correction prohibition time that is substantially equal to the deviation time T5.

FIG. 4 is a diagram showing the calculation state of the remaining fuel amount over time when the vehicle is traveling at high speed (around 100 km/h). FIG. 5 is a diagram in which a part of the section of FIG. 4 is extracted and enlarged. In FIG. 4, the vehicle speed S, the uncorrected remaining amount B-2, the corrected remaining amount B-1, the short-time average value A, and the correction flag F are illustrated. The reference numerals in FIG. 4 are the same as those in FIG. The correction flag F is equal to or higher than a predetermined speed, and the deviation determination between the corrected remaining amount B-1 and the remaining fuel amount A is established, and the remaining fuel amount A and the short-term average value A based on the sender calculation values are equal to predetermined values (for example, It turns on when it is within 1 liter), and turns off otherwise. In short, it is turned on when the correction conditions A to C described later are satisfied.

In FIG. 4, when the difference between the remaining fuel amount A and the short-term average value A is a predetermined value L1 (for example, ±3 liters (L)) or more and the state continues for a predetermined time T4 (for example, 120 seconds), It is determined that there is a deviation in the remaining fuel amount A, and the deviation time T5 including the predetermined time T4 is continuously counted until the magnitude relationship between the short-term average value A and the remaining fuel amount A is reversed (from 1600 seconds in FIG. 4). Keep counting). When the magnitude relation between the short-term average value A and the remaining fuel amount A is reversed (at 1900 seconds in FIG. 4), the counting of the deviation time T5 is stopped, and the correction prohibition time T6 is set to be substantially the same as the deviation time T5. Therefore, the correction of bringing the remaining fuel amount B close to the remaining fuel amount A is prohibited.

In this case, an upper limit can be set for the count of the deviation time T5. For example, 600 seconds is set as the upper limit of the deviation time T5. Further, the correction prohibition time T6 is prohibited for a predetermined time (T6=T5+α, α is, for example, 60 seconds) after the magnitude relationship between the short-time average value A and the remaining fuel amount A is reversed. This eliminates unnecessary correction and improves the residual fuel calculation accuracy.

More specifically, in FIG. 5, the correction is prohibited even if the correction flag F is turned on during the counting of the deviation time T5 and the correction prohibition time T6. The correction flag F is turned on when the difference between the short-term average value A and the remaining fuel amount A becomes small (for example, 1 liter). Even when such a correction flag F is set, it is determined that the liquid surface is not stable until a time substantially equal to the deviation time T5 (correction prohibition time T6) elapses, and the correction is prohibited.

FIG. 6 is a flowchart relating to the normal correction of the remaining fuel amount. In this flowchart, two types of filter values having different responsiveness (remaining fuel amount A and short-term average value A) are compared, and when they match for a predetermined time or more, the liquid level in the fuel tank is stable. It is determined that there is a fuel remaining amount, and the remaining fuel amount is corrected (normal correction). First, five correction conditions A to E are defined. If all of these correction conditions A to E (AND conditions) are cleared, the remaining fuel amount B is corrected.

The correction condition A is a case where there is a difference between the fuel sender-based remaining fuel amount A and the consumption-based remaining fuel amount B. If there is a deviation, the correction condition A will be cleared. The correction condition B is a case where the vehicle speed is equal to or higher than a predetermined value (the vehicle has not stayed on the slope for a long time). The correction condition C is when the difference between the two sender-based filter values (fuel remaining amount A and short-term average value A) is small, that is, when the liquid surface is stable. The correction condition D is a case where the correction conditions A to C are satisfied for a first predetermined time T1 (for example, 5 minutes) or more. The correction condition E is neither the deviation time T5 nor the correction prohibition time T6, that is, the correction prohibition condition is not satisfied.

First, when the remaining fuel amount calculation is started (S1), a short-time average value A (for example, a short-time 3 second average value) input from the fuel sender 4 is calculated (S2). The remaining fuel amount A of the sender base is calculated based on this calculated value (S3). For example, the remaining fuel amount A is calculated based on the following equation.
Remaining fuel amount A(n)=remaining fuel amount A(n-1)−Ka (short-time average value A<remaining fuel amount A) (5)
Remaining fuel amount A(n)=remaining fuel amount A(n-1)+Ka (short-time average value A>remaining fuel amount A) (6)

Next, the fuel consumption for each calculation cycle is integrated to integrate the consumed fuel (S4), and the remaining fuel amount B is calculated (S5). This is the remaining fuel amount calculation based on the fuel consumption amount. For example,
Remaining fuel amount B(n) = Remaining fuel amount B(n-1)-Fuel consumption amount (integrated value) (3)

Next, it is determined whether or not the remaining fuel amount A has no margin (S6). That is, it is determined whether the remaining fuel amount is equal to or less than a predetermined value C0 (for example, 10 liters), and if the remaining fuel amount A has a margin (when the remaining fuel amount is larger than the predetermined value C0), the correction conditions A to D are set. Set the correction threshold applied to the following. That is, the correction threshold C1 in the correction condition A=large, the correction threshold C2 in the correction condition C=small, the correction threshold V1 in the correction condition B=large, and the correction threshold T2 in the correction condition D=large. To do. However, the correction threshold value is set as described above only when the difference between the sender-based fuel remaining amount A and the consumption-based fuel remaining amount B is large. For example, C1=3 liters (L), C2=1 liter (L), V1=20 km/h, and T2=12 seconds.

When the remaining fuel amount A has no margin, that is, when the remaining fuel amount is equal to or less than the predetermined value Co, the correction threshold value C1 in the correction condition A=small, the correction threshold value C2 in the correction condition C=large, the correction condition B. The correction threshold value V1 is small and the correction threshold value T2 in the correction condition D is small. This correction threshold value is corrected even when the difference between the fuel amount A based on the sender and the fuel amount B based on the consumption amount is small, and corresponds to the fuel exhaustion. For example, C1=1 liter (L), C2=2 liter (L), V1=10 km/h, and T2=6 seconds.

Then, after measuring the remaining fuel amount A (S6), the difference between the remaining fuel amount B and the remaining fuel amount A is determined (S9). In this case, it branches into three routes. In the first route, when the difference between the two is extremely large and is larger than a predetermined value C3 (for example, 10 liters (L)), the forced correction is performed. That is, when the difference (absolute value) between the remaining fuel amount B and the remaining fuel amount A exceeds a predetermined value (for example, 10 liters (L)), the difference between the two is unconditionally corrected by the correction threshold C1 of the correction condition A. Correct until it becomes below.

In the second route, when the difference between the remaining fuel amount B and the remaining fuel amount A exceeds the correction threshold value C1 (the difference from the sender value is large), it is determined that there is a difference between them, and the correction condition A is satisfied. If the third route is equal to or lower than the correction threshold value C1 (there is no difference from the sender value), it is determined that there is no difference between the two and ends without correction (S14).

If the correction condition A is satisfied (S9:Y), then the own vehicle speed is determined (S10). When the vehicle speed is equal to or higher than the correction threshold V1 (predetermined speed) (S10:Y), it is determined that the vehicle is unlikely to be affected by the inclination or the curve, and the correction condition B is satisfied. If the vehicle speed is lower than the correction threshold value V1 (S10:N), it is determined that the vehicle is easily affected by the inclination or the curve, and the process ends without correction (S14).

If the correction condition B is also satisfied (S10: Y), then it is determined whether or not the absolute value of the short-term average value A-the remaining fuel amount A is equal to or smaller than the correction threshold value C2 (small filter deviation) (S11). ). The “filter” referred to herein as “small filter deviation” or “large filter deviation” means two types of fuel remaining amount A and short-time average value A, and when the difference is large, it is called “large filter deviation”. When the difference is small, it is called “small filter deviation”. When the absolute value of the short-time average value A-the remaining fuel amount A is equal to or less than the correction threshold value C2 (S11: Y), it is determined that there is no difference between the two sender-based filters (fuel remaining amount A and short-time average value A). Then, the correction condition C is satisfied. When the absolute value of the short-time average value A−the remaining fuel amount A is larger than the correction threshold value C2 (S11:N), the difference between the two sender-based filters (the remaining fuel amount A and the short-time average value A) is large. It is judged that the liquid surface is largely unstable, and the process ends without correction (S14).

If the correction condition C is also satisfied, then each condition satisfaction time is determined (S12). This is the case where the correction condition A is satisfied for the first predetermined time T1 (for example, 5 minutes) or more and the correction condition C is satisfied for the predetermined time T2 (for example, 12 seconds) or more (S12:Y). If each condition is satisfied for less than the predetermined time T1, or if the correction condition C is satisfied for less than the predetermined time T2, it is determined that the liquid surface is unstable, and the process ends (S14).

Furthermore, if each condition satisfaction time of the correction condition D is satisfied (S12:Y), then it is determined whether the correction prohibition condition is satisfied (S15). The correction prohibition condition determines whether or not the deviation time T5 and the correction prohibition time T6 are being counted. When the deviation time T5 is being counted and when the correction inhibition time T6 is being counted (S15:Y), the process ends without correction (S14).

If it is not the correction prohibition condition (S15: N), all the conditions of the correction conditions AE are cleared, so the correction is made to bring the remaining fuel amount B close to the remaining fuel amount A. The correction to bring the remaining fuel amount B closer to the remaining fuel amount A is performed by the following formula.
Remaining fuel amount B (n) = Remaining fuel amount (n) + Kb
(Kb is a fixed value or a value proportional to (remaining fuel amount A-remaining fuel amount B)) (7)

As described above, in the present embodiment, by taking advantage of the sender system (1) and the injector system (2), correction is performed when the liquid level is stable, and a more accurate fuel remaining amount is calculated. That is, in consideration of the vehicle speed as well, it is a predetermined state that the liquid level is stable at a predetermined speed or more (for example, 20 km/h or more) and the difference between the short-time average value A and the remaining fuel amount A is a predetermined value or less. When it continues for a time or more (for example, 10 seconds), the remaining fuel amount B is corrected so as to approach the remaining fuel amount A. On the contrary, when the difference between the short-term average value A and the remaining fuel amount A exceeds the predetermined value, it is determined that the liquid level is not stable, the remaining fuel amount B is not corrected, and the fuel consumption amount is directly subtracted. By doing so, unnecessary correction is suppressed.

In particular, when the difference between the short-term average value A and the remaining fuel amount A is a predetermined value L1 or more and the state continues for a predetermined time T4 or more, it is determined that there is a difference in the remaining fuel amount A, and the difference including the predetermined time T4 is included. The time T5 is continuously counted, and when the magnitude relationship between the short-term average value A and the remaining fuel amount A is reversed, the counting of the deviation time T5 is stopped, and the difference time T5 is the same as the deviation time T5 or a predetermined time period ( A long time (for example, 60 seconds) is set as the correction prohibition time T6, and the correction prohibition time T6 prohibits correction in which the remaining fuel amount B approaches the remaining fuel amount A.

As a result, the correction prohibition time T6 that is almost equal to the deviation time T5 is set, and the correction is prohibited during the deviation time T5 and the correction prohibition time T6. It is possible to calculate (display) the remaining fuel amount.

It should be noted that the present invention is not limited to the above embodiment, and many modifications and changes can be made within the scope of the present invention. For example, in the above embodiment, the correction prohibition condition E is set, and when the condition is not satisfied and all of the other correction conditions A to D are satisfied, the correction of bringing the remaining fuel amount B close to the remaining fuel amount A can be performed. However, the present invention is not limited to this, and when the correction prohibition condition is not satisfied and at least one of the correction conditions A to D is satisfied, the correction of bringing the remaining fuel amount B close to the remaining fuel amount A can be performed. You may

1 Fuel Remaining Amount Calculator 2 Control Unit 3 Vehicle Speed Sensor 4 Fuel Sender 5 Fuel Consumption Amount Detection Unit 6 Fuel Remaining Amount Display 7 Short Time Average 8 Fuel Remaining Amount Calculation Unit 9 Integration Unit

Claims (1)

Based on the remaining fuel amount (B) calculated by subtracting the fuel consumption calculated from the injector valve opening time from the fuel amount at the time of refueling, and the input from the fuel sender that detects the liquid level of the fuel tank, In a fuel remaining amount calculation device for a vehicle having a control unit for calculating a final fuel remaining amount using the fuel remaining amount (A) smoothed by calculation,
When the difference between the remaining fuel amount (B) and the remaining fuel amount (A) is equal to or greater than a first predetermined value (C1) for a first predetermined time (T1) or more, the control unit , It is determined that there is a deviation in the remaining fuel amount (B) and correction is necessary, and correction is performed to bring the remaining fuel amount (B) closer to the remaining fuel amount (A),
However, the control unit determines that the difference between the short-term average value (A) of the fuel sender input and the fuel remaining amount (A) is a second predetermined value (L1) or more, and the state is the second predetermined time ( When it continues for T4) or more, it is determined as the deviation of the remaining fuel amount (A), the deviation time (T5) is continuously counted including the second predetermined time, and the short-time average value (A) and the fuel When the magnitude relationship with the remaining amount (A) is reversed, or when the short-time average value (A) and the remaining fuel amount (A) become the third predetermined value (L2) or less during the counting, the deviation The counting of the time (T5) is stopped, and the remaining fuel amount (B) is set to the correction prohibition time (T6) which is equal to or longer than the deviation time (T5) by a predetermined time (α). A remaining fuel amount calculating device, which prohibits correction to approach the remaining fuel amount (A).

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