Information processing device

Abstract

Improve the accuracy of fuel consumption calculations. [Solution] An information processing device (100) that calculates the fuel consumption of an internal combustion engine (1) using a calculation formula, comprising: an acquisition means for acquiring the actual change in energizing time due to a change in the fuel pressure of an injector (5) that injects fuel into the internal combustion engine (1); and a correction means for correcting the calculation formula based on the actual change in energizing time acquired by the acquisition means and the change in energizing time in the design characteristics.

Description

[Technical Field]

[0001] The present invention relates to an information processing device that calculates the fuel consumption of an internal combustion engine using a calculation formula. [Background technology]

[0002] In Europe and Japan, it is mandatory to install onboard fuel consumption measurement devices (OBFCMs) in automobiles. As a technology for calculating the fuel consumption of an internal combustion engine, Patent Document 1 discloses a fuel consumption measuring device for an internal combustion engine that calculates fuel consumption based on a detected intake air volume and a detected air-fuel ratio. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Utility Model Publication No. Showa 63-181924 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] The fuel consumption (L) of an internal combustion engine is calculated using the following formula (1), for example, the amount of air detected by a sensor (detected air amount) (L), air density (g / L), fuel density (g / L), and the controlled air-fuel ratio (controlled air-fuel ratio). Various correction amounts are coefficients that correct the detected air amount according to water temperature, transients, purging, etc. In addition, the fuel learning value is a coefficient that corrects the detected air amount to absorb characteristic deviations of the exhaust sensor, airflow sensor, etc. fuel consumption = (Detected air volume, various correction amounts, fuel learning value, air density) / controlled air-fuel ratio, fuel density ...(1)

[0005] At present, deviations in the flow rate characteristics of injectors due to aging deterioration or the like are not reflected, resulting in a discrepancy between the fuel amount that is actually injected and the fuel consumption amount calculated by Equation (1). In detail, when the injector is clogged due to aging deterioration or the like, the fuel flow rate (the amount of fuel per unit time) from the injector decreases, leading to an insufficient fuel amount, so control is performed to increase the fuel amount. In this case, the actually injected fuel amount remains the same as before the clogging, but the fuel consumption amount calculated by Equation (1) increases, degrading the calculation accuracy of the fuel consumption amount.

[0006] The present invention has been made in view of the above-described problems, and an object thereof is to improve the calculation accuracy of fuel consumption amount. [Means for Solving the Problems]

[0007] An information processing apparatus of the present invention is an information processing apparatus that calculates a fuel consumption amount of an internal combustion engine using an arithmetic expression, and is characterized by comprising: an acquisition unit that acquires a change in actual energization time accompanying a change in fuel pressure of an injector that injects fuel into the internal combustion engine; and a correction unit that corrects the arithmetic expression based on the change in the actual energization time acquired by the acquisition unit and a change in energization time in design characteristics. [Effects of the Invention]

[0008] According to the present invention, it is possible to improve the calculation accuracy of fuel consumption amount. [Brief Description of the Drawings]

[0009] [Figure 1] It is a diagram showing a schematic configuration of a main part of an automobile according to an embodiment. [Figure 2] It is a diagram showing a functional configuration of an ECM according to the embodiment. [Figure 3] It is a flowchart showing an example of processing executed by the ECM according to the embodiment. [Figure 4] It is a time chart of flow rate characteristic deviation detection processing executed by the ECM according to the embodiment. [Figure 5]This characteristic diagram shows an example of the relationship between the energizing time of the injector and the fuel flow rate during idling. [Modes for carrying out the invention]

[0010] An information processing device (100) according to one embodiment of the present invention is an information processing device (100) that calculates the fuel consumption of an internal combustion engine (1) using a calculation formula, and comprises an acquisition means for acquiring the actual change in energizing time due to a change in the fuel pressure of an injector (5) that injects fuel into the internal combustion engine (1), and a correction means for correcting the calculation formula based on the actual change in energizing time acquired by the acquisition means and the change in energizing time in the design characteristics. This makes it possible to calculate the fuel consumption while reflecting the deviation in the flow characteristics of the injector (5), and improves the accuracy of the fuel consumption calculation. [Examples]

[0011] Hereinafter, preferred embodiments of the present invention will be described with reference to the attached drawings. Figure 1 shows a schematic configuration of the main parts of an automobile according to an embodiment. The automobile is equipped with engine 1 as its power source. Engine 1 is an internal combustion engine with multiple cylinders, and is connected to an intake manifold 4 which forms the intake passage and an exhaust manifold 12 which forms the exhaust passage. On the intake side, the amount of air drawn in from the air cleaner 2 is adjusted by the throttle valve 3, and the intake air that has passed through the intake manifold 4 is mixed with the fuel injected from the injector 5. In engine 1, the intake valve 7 is opened to introduce the mixture into the combustion chamber, it is compressed by the piston 8, and ignited by the spark plug 9 to cause combustion. The burnt mixture expands, pushing down the piston 8 and rotating the crankshaft 10. On the exhaust side, when the exhaust valve 11 opens, the burnt mixture passes through the exhaust manifold 12, is purified by the three-way catalytic converter 13, and is then exhausted.

[0012] Although not shown in Figure 1, an ECM (Engine Control Module) 100 is installed in the automobile. The ECM 100 controls the engine, including fuel supply control and ignition timing control. The ECM 100 is composed of a computer unit that includes, for example, a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), flash memory for storing backup data, input ports, and output ports.

[0013] In this embodiment, the ECM100 functions as an information processing device to which the present invention is applied. The following description will focus on the functions of the information processing device to which the present invention is applied. Figure 2 shows the functional configuration of the ECM100. As shown in Figure 2, the ECM 100 includes a fuel consumption calculation unit 101, a fuel pressure setting unit 102, a flow characteristic deviation calculation unit 103, and a fuel learning value calculation unit 104.

[0014] The fuel consumption calculation unit 101 calculates the fuel consumption using the fuel learning value calculated by the fuel learning value calculation unit 104 according to the calculation formula (1) described above.

[0015] The fuel pressure setting unit 102 sets the fuel pressure, which is the pressure of the fuel supplied to the injector 5, by PWM control of the fuel pump (not shown) when it performs a flow characteristic deviation detection process to detect a deviation in the flow characteristics of the injector 5. The flow characteristic deviation detection process is performed when the operating state of the engine 1 is stable (when the operating state of the engine 1 is approximately constant), and in this embodiment, it is performed when the engine is idling. When the fuel pressure setting unit 102 performs the flow characteristic deviation detection process in the idling state, it sets the fuel pressure P during normal control in the idling state. Normal (Hereafter, P N (as written), fuel pressure P N A fuel pressure P smaller than Low (Hereafter, P L Set to (as indicated). Fuel pressure P LThe fuel pressure level to be set may be appropriately determined, for example, the fuel pressure P during normal control N is set to about 1 / 4 of that value.

[0016] The flow rate characteristic deviation calculation unit 103, when executing the flow rate characteristic deviation detection process, calculates the change T in the actual energization time accompanying the fuel pressure change (P N →P L ) of the injector 5 aging , and calculates the flow rate characteristic deviation based on this energization time change T aging and the energization time change T in the design central characteristic std . Figure 5 is a characteristic diagram showing an example of the relationship between the energization time (msec) of the injector 5 and the fuel flow rate (L / min) in an idling state. In the idling state, in order to keep the amount of fuel supplied from the injector 5 to the engine 1 substantially constant, it is necessary to operate the injector 5 so as to secure a fuel flow rate corresponding to the fuel pressure. For example, when the fuel pressure P during normal control N is reached, the fuel flow rate FL N is secured, and when the fuel pressure P L (<P N ) is reached, the fuel flow rate FL L (>FL N ) is secured. Here, in the design central characteristic of the injector 5, as shown by the characteristic line 501, when the fuel pressure P N is reached, the energization time T1' is required to secure the fuel flow rate FL N , and when the fuel pressure P L is reached, the energization time T2' is required to secure the fuel flow rate FL L . On the other hand, in the actual injector 5 (the injector 5 that has undergone aged deterioration or the like), as shown by the characteristic line 502, when the fuel pressure P N is reached, the energization time T1 is required to secure the fuel flow rate FL N , and when the fuel pressure P L is reached, the energization time T2 is required to secure the fuel flow rate FL L . The flow rate characteristic deviation of the injector 5 is defined as (T std =T2'-T1') / (T agingThis is expressed as =T2-T1). The greater the degree of injector 5's deterioration, the greater the change in the actual energizing time T due to the change in fuel pressure of injector 5. aging It will get bigger.

[0017] The fuel learning value calculation unit 104 calculates the fuel learning value included in the calculation formula of equation (1) based on the flow characteristic deviation calculated by the flow characteristic deviation calculation unit 103. The specific method of calculating the fuel learning value based on the flow characteristic deviation is not limited, and the explanation is omitted, but the change in energization time T in the design center characteristic is std The actual change in energizing time T aging The larger the deviation, i.e., the greater the flow characteristic deviation T. std / T aging The smaller the value, the lower the calculated fuel learning value will be, resulting in a lower calculated fuel consumption.

[0018] In this embodiment, the flow rate characteristic deviation calculation unit 103 and the fuel learning value calculation unit 104 function as acquisition means and correction means as defined in the present invention.

[0019] Figure 3 is a flowchart showing an example of the process performed by the ECM100. The flowchart in Figure 3 is executed when the engine 1 is in a stable operating state, which in this embodiment is when it is idling. Note that the flowchart in Figure 3 may be executed every time the engine is idling, or it may be executed when the engine is idling and a predetermined time has elapsed since the previous execution. Figure 4 is a time chart of the flow characteristic deviation detection process performed by the ECM100, showing the on / off states of the flow characteristic deviation detection process, the energizing time of the injector 5, and the changes in fuel pressure and air volume.

[0020] In step S1, the flow characteristic deviation calculation unit 103 calculates the fuel pressure P after the start of the flow characteristic deviation detection process (time t1 in Figure 4). N Furthermore, the system waits until a predetermined time T(S) has elapsed, and when that predetermined time T(S) has elapsed (time t2 in Figure 4), it proceeds to step S2. In step S2, the flow characteristic deviation calculation unit 103 calculates the fuel flow rate FL as explained in Figure 5.N The energizing time T1 is obtained to ensure the desired result. The energizing time T1 is calculated, for example, as the average value of the energizing time over a predetermined time T(S).

[0021] In step S3, the fuel pressure setting unit 102 sets the fuel pressure P N From fuel pressure P L Change to this (times t2-t3 in Figure 4). In step S4, the flow characteristic deviation calculation unit 103 calculates the fuel pressure P L After the change (time t3 in Figure 4), fuel pressure P L Then, the system waits until a predetermined time T(S)' has elapsed, and when that time has elapsed (time t4 in Figure 4), it proceeds to step S5. The predetermined time T(S)' in step S4 may be the same as or different from the predetermined time T(S) in step S1. In step S5, the flow characteristic deviation calculation unit 103 calculates the fuel flow rate FL as explained in Figure 5. L The energizing time T2 is obtained to ensure the desired result. The energizing time T2 is calculated, for example, as the average value of the energizing time over a predetermined time T(S)'.

[0022] In step S6, the flow characteristic deviation calculation unit 103 calculates the change in energization time T aging (=T2-T1) and the change in energizing time T at the design center characteristic. std Based on (=T2'-T1'), the flow characteristic shift T std / T aging Calculate. In step S7, the fuel learning value calculation unit 104 calculates the flow characteristic deviation T calculated in step S6. std / T aging Based on this, the fuel learning value included in the calculation formula of equation (1) is calculated. As described above, the change in energization time T in the design central characteristic std The actual change in energizing time T aging The larger the discrepancy, the lower the calculated fuel learning value will be in order to estimate fuel consumption.

[0023] In the example shown in Figure 3, after the start of the flow characteristic deviation detection process, the fuel pressure P during normal control in the idling state is... NThe system is designed to obtain the corresponding power-on time T1, but the power-on time T1 may be obtained in advance.

[0024] The above process makes it possible to calculate fuel consumption while reflecting the deviation in the flow characteristics of injector 5, thereby improving the accuracy of fuel consumption calculation. Specifically, when clogging occurs in the injector due to aging or other reasons, and the fuel flow rate decreases in response to the injection command to injector 5, the change in energization time T in the design center characteristic is calculated. std The actual change in energizing time T aging The larger the discrepancy, the more the fuel learning value is calculated to underestimate fuel consumption, thus preventing overestimation of fuel consumption.

[0025] Furthermore, since the flow characteristic deviation detection process is performed when the engine 1 is operating in a stable state, such as during idling, the impact on drivability caused by the execution of the flow characteristic deviation detection process can be reduced.

[0026] Although embodiments of the present invention have been described in detail above with reference to the drawings, each embodiment is merely a specific example of how the present invention can be implemented. The technical scope of the present invention is not limited to each embodiment. Various modifications of the present invention are possible without departing from its spirit, and these modifications are also included within the technical scope of the present invention. In this embodiment, the calculation formula is corrected by calculating a coefficient called the fuel learning value, but this is not the only example. For example, the calculation formula for calculating fuel consumption may include a coefficient corresponding to the deviation in the injector's flow characteristics, in addition to the fuel learning value. An information processing device to which the present invention is applied is composed of a computer device equipped with, for example, a CPU, ROM, RAM, etc., and the functions of each means are realized when the CPU executes a predetermined program stored in, for example, ROM. [Explanation of symbols]

[0027] 1: Engine, 5: Injector, 100: ECM, 101: Fuel consumption calculation unit, 102: Fuel pressure setting unit, 103: Flow characteristic deviation calculation unit, 104: Fuel learning value calculation unit

Claims

1. An information processing device that calculates the fuel consumption of an internal combustion engine using a calculation formula, An acquisition means for acquiring the actual change in energizing time due to changes in the fuel pressure of an injector that injects fuel into the internal combustion engine, An information processing apparatus characterized by comprising a correction means for correcting the calculation formula based on the change in the actual energizing time acquired by the acquisition means and the change in the energizing time in the design characteristics.

2. The information processing apparatus according to claim 1, characterized in that the correction means corrects the calculation formula so that the fuel consumption is calculated to be smaller the greater the discrepancy between the change in the current supply time in the design characteristics and the actual change in current supply time.

3. The information processing device according to claim 1 or 2, characterized in that the acquisition means acquires the change in the actual energization time when the operating state of the internal combustion engine is stable.

4. The information processing apparatus according to claim 1 or 2, characterized in that the correction means corrects the calculation formula by calculating the coefficients included in the calculation formula.

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