JP6922116B1 - Airflow sensor characteristic information generation system and engine control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air flow sensor characteristic information generation system for improving the responsiveness of an air flow sensor. SOLUTION: A pressure step response device Z that changes the pressure of air flowing in a pipe of a pipe 20 in steps, an air flow sensor 1 and a high response flow meter 10 for measuring the flow rate of air flowing in the pipe of a pipe 20, and an air flow sensor. An airflow sensor characteristic information generation system W1 including a measuring device 110 for calculating characteristic information, in which the measuring device 110 airflows while the pressure step response device Z changes the pressure of the pipe 20 in a stepped manner. The data acquisition unit 110 that acquires the first air flow rate measured by the sensor 1 and the second air flow meter measured by the high response flow meter, the second air flow rate is used as the reference flow rate, and the reference flow rate and the first air flow rate are used. It also has an airflow sensor characteristic information calculation unit 113 that calculates the regression transfer function of the airflow sensor 1 as the aerosensor characteristic information. [Selection diagram] Fig. 1

Description

The present invention relates to an air flow sensor characteristic information generation system and an engine control system.

Conventionally, an engine control unit (ECU (Electronic Control Unit)) mounted on an automobile or the like has been an engine using an air flow sensor provided in an intake passage of an engine and detection values detected by various other sensors. Is controlled to operate optimally. Among various sensors, the air flow rate (intake air amount) that flows into the engine detected by the airflow sensor is an important factor for controlling the engine to operate optimally. ..

Further, in order to detect the amount of intake air to the engine, a heat ray type (heat type) air flow sensor is generally used. The heat ray type air flow sensor is equipped with a heating element (white wire), supplies power to the heating element to generate heat, and measures the air flow rate by utilizing the fact that the amount of heat transferred to the air depends on the air flow velocity. It has become like.
As described above, the heat ray type airflow sensor used for controlling the engine of an automobile is disclosed in, for example, Patent Document 1.

Japanese Unexamined Patent Publication No. 10-306740

By the way, the heat ray type airflow sensor of the prior art has a technical problem that it does not have a responsiveness capable of detecting a steep flow rate change. Therefore, the conventional heat ray type air flow sensor can measure an accurate value when used in an environment where the flow rate may change sharply, for example, the flow rate of air flowing into an automobile engine (intake air amount). There wasn't. As a result, even if the ECU (Electronic Control Unit) controls the engine using the intake air amount (measured value) of the engine measured by the heat ray type air flow sensor, there is a risk that the engine cannot be controlled so as to perform the optimum operation. was there. As an automobile engine, a heat ray type airflow sensor (general-purpose heat ray type airflow sensor) that does not have a responsiveness that can detect a steep flow rate change is generally used.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an air flow sensor characteristic information generation system for improving the responsiveness of an air flow sensor. Another object of the present invention is to provide an engine control system that controls an engine by using the airflow sensor characteristic information generated by the airflow sensor characteristic information generation system.

The first aspect of the present invention for solving the above problems is connected to an air flow sensor installed in an intake pipe of an engine installed in an engine test device and measuring the flow rate of air flowing into the engine, and the intake pipe. An airflow sensor characteristic information generation system including a high response flow meter for measuring the flow rate of air flowing into the engine and a measuring device for calculating air flow sensor characteristic information. The high response flow meter is the air flow sensor. It is a flow meter that is more responsive to fluctuations in the flow rate of air than the above, and in the measuring device, the engine test device drives the engine to cause a steep change in the flow rate of air flowing into the engine. During the process, the data acquisition unit that acquires the first air flow rate measured by the air flow sensor and the second air flow rate measured by the high response flow meter, and the acquired second air flow rate are used as reference flow rates. and having a flow sensor characteristic information calculation unit for calculating a regression transfer function of the airflow sensor as the d Afro sensor characteristic information by using the reference flow rate and the first air flow rate the acquired.

According to a first aspect of the present invention, the air flow sensor characteristics information showing characteristics of d Afro sensor (regression transfer functions) are obtained. Therefore, by using the airflow sensor characteristic information (return transfer function) to correct the measured value measured by the airflow sensor, it is almost the same as the one measured by the "high response flow meter", which has higher responsiveness than the airflow sensor. The air flow rate can be obtained (the accurate air flow rate can be obtained).
That is, according to the present invention, a commonly used "air flow sensor" can be upgraded to the same level of responsiveness as a "high response flow meter" having higher responsiveness than an air flow sensor.

Further, it is desirable that the air flow sensor is a hot wire type air flow sensor and the high response flow meter is an ultrasonic flow meter or a lamina flow meter.

Further, the airflow sensor characteristic information calculation unit uses the reference flow rate as an input value, uses the first air flow rate measured by the airflow sensor corresponding to the reference flow rate as an output value, performs a Fourier analysis calculation, and transmits the airflow sensor. It is desirable that the characteristics are calculated, the transfer function is calculated from the calculated transfer characteristics, and the regression transfer function is calculated from the transfer function.

A second aspect of the present invention is an engine control system including an engine control device that stores the regression transfer function generated by the airflow sensor characteristic information generation system and an engine provided with the airflow sensor. The air flow sensor is installed in the intake pipe of the engine, measures the air flow rate flowing into the engine, and transmits the measured air flow rate to the engine control device. The air flow rate measured by the air flow sensor is acquired, a corrected air flow rate obtained by correcting the acquired air flow rate is calculated using the stored regression transfer function, and the engine is controlled using the corrected air flow rate. It is characterized in that it is designed to perform.

According to the second aspect of the present invention, in an engine control system that controls an engine equipped with an airflow sensor that does not have a responsiveness that can detect a steep flow rate change, air flowing into the engine measured by the airflow sensor. The operation of the engine can be controlled after correcting the flow rate to an accurate value. Therefore, according to the engine control device of the present invention, highly accurate engine control is realized.

According to the present invention, it is possible to provide an airflow sensor characteristic information generation system for improving the responsiveness of an airflow sensor. Further, according to the present invention, it is possible to provide an engine control system that controls an engine by using the airflow sensor characteristic information generated by the airflow sensor characteristic information generation system.

It is a schematic diagram which showed the structure of the air flow sensor characteristic information generation system of 1st Embodiment of this invention. It is a flowchart which showed the procedure of the airflow sensor characteristic information generation processing performed by the airflow sensor characteristic information generation system of 1st Embodiment of this invention. It is a schematic diagram which showed the input / output relationship of the transmission characteristic of the airflow sensor calculated by the airflow sensor characteristic information generation system of 1st Embodiment of this invention. It is a schematic diagram for demonstrating the process of fitting and identifying the transfer function to the transmission characteristic of the airflow sensor calculated by the airflow sensor characteristic information generation system of 1st Embodiment of this invention. It is a schematic diagram which showed the structure of the air flow sensor characteristic information generation system of 2nd Embodiment of this invention. It is a flowchart which showed the procedure of the airflow sensor characteristic information generation processing performed by the airflow sensor characteristic information generation system of the 2nd Embodiment of this invention. It is a schematic diagram for demonstrating the utilization example of the airflow sensor characteristic information generated by the airflow sensor characteristic information generation system of the 1st and 2nd embodiments of this invention, and is the engine control device which stores the airflow sensor characteristic information. The engine control system to have is shown. A regression value obtained by reverting the measured value of the air flow sensor using the air flow sensor characteristic information calculated by the air flow sensor characteristic information generation system of the first embodiment of the present invention, the measured value of the air flow sensor, and the measured value of the high response flow meter. It is a graph which showed the relationship with the reference flow rate which is.

Hereinafter, the airflow sensor characteristic information generation system of the embodiment (first embodiment, second embodiment) of the present invention will be described with reference to the drawings.

<< First Embodiment >>
First, the configuration of the airflow sensor characteristic information generation system according to the first embodiment of the present invention will be described with reference to FIG.

Here, FIG. 1 is a schematic diagram showing the configuration of the airflow sensor characteristic information generation system of the first embodiment.

As shown in FIG. 1, the airflow sensor characteristic information generation system W1 of the first embodiment includes a pipe 20 in which a first valve 21 and a second valve 22 are installed, supplies pressurized air to the pipe 20, and has a first degree. A pressure step response device Z that controls the opening and closing operations of the first and second valves 21 and 22 to change the pressure of the air in the pipe 20 in steps, and a heat ray type air flow sensor that measures the flow rate of air flowing through the pipe 20. (Hereinafter, simply referred to as "airflow sensor") 1, a high response flow meter 10 for measuring the air flow rate flowing through the pipe 20, and airflow sensor characteristic information (transmission function, regression transmission function) indicating the characteristics of the airflow sensor 1 are calculated. It has a measuring device 110.

The high response flow meter 10 is an air flow meter having a higher (faster) response to fluctuations in the air flow rate than the air flow sensor 1. For example, an ultrasonic flow meter or a laminar flow meter (laminar flow meter) can be used for the high response flow meter 10. In the illustrated example, the case where the high response flow meter 10 is a laminar flow meter is shown.
Further, as the air flow sensor 1 of the present embodiment, one having no responsiveness capable of detecting a steep flow rate change is used (a general-purpose air flow sensor is used).

Further, the pressure step response device Z includes a pipe (circular pipe) 20 penetrating both ends, a pressurized air supply device 30 for supplying pressurized air to the pipe 20, and one end side (pressurized air) of the pipe 20. The first valve 21 installed in the pipe on the inlet side of the pipe 20 and the second valve 22 installed in the pipe on the other end side (outlet side of the pressurized air) of the pipe 20 and each valve (first valve). , The valve operating device 40 that controls the opening / closing operation of the second valves 21 and 22) is provided.

Further, the pressurized air supply device 30 is connected to one end of the pipe 20, and pressurized air of a predetermined pressure flows into the pipe of the pipe 20 from one end of the pipe 20.
Further, the pipe 20 has a first straight pipe portion 20a and a first straight pipe portion 20a which are connected to the pressurized air supply device 30 and extend in the first direction (Y direction in the drawing) as well as penetrating both ends. It is formed in a substantially L shape including a second straight pipe portion 20b that bends at a substantially right angle from the pipe and extends in a second direction (X direction in the drawing). A high response flow meter 10 is attached to the free end (right end in the drawing) of the second straight pipe portion 20b.

Further, the valve operating device 40 transmits an opening / closing control signal to the two valves (first and second valves 21 and 22) to control the opening / closing state of the two valves (first and second valves 21 and 22). By doing so, the pressurized air supplied from the pressurized air supply device 30 is confined between the two valves (first and second valves 21, 22), and then the open / closed state of the second valve 22 is controlled. The pressure of the pressurized air (fluid) in the pipe 20 is changed in steps. With this configuration, a high-speed change in flow rate can be generated inside the pipe 20.

The air flow sensor 1 is attached to the other end side (right end side in the drawing) of the second straight pipe portion 20b of the pipe 20 with respect to the second valve 22, and the inside of the pipe 20 of the pipe 20 is installed. , The flow rate of air flowing in the direction from one end to the other end (X1 direction shown in FIG. 1) is measured, and the measured measured value (first air flow rate) is transmitted to the measuring device 110.
Further, the high response flow meter 10 is attached by being connected to the free end (the right end when facing in the drawing) of the second straight pipe portion 20b, and the inside of the pipe 20 is directed from one end to the other end (the direction (). The flow rate of the air flowing in the X1 direction shown in FIG. 1) and flowing out from the other end is measured, and the measured measured value (second air flow rate) is transmitted to the measuring device 110.

The measuring device 110 includes the measured value (first air flow rate) measured by the air flow sensor 1 while the pressure step response device Z is changing the pressure of the pressurized air (fluid) of the pipe 20 in a stepped manner. The measured value (second air flow rate) measured by the high response flow meter 10 is acquired.
Further, the measuring device 110 uses the measured value (second air flow rate) measured by the high response flow meter 10 as the reference flow rate, and uses the reference flow rate and the first air flow rate measured by the air flow sensor 1 to provide air flow sensor characteristics. Calculate information (transfer function, regression transfer function).

Next, the functional configuration of the measuring device 110 constituting the airflow sensor characteristic information generation system W1 of the first embodiment will be described.
The measuring device 110 includes a control unit 111, a data acquisition unit 112, and an air flow sensor characteristic information calculation unit 113.

The hardware configuration of the measuring device 110 is not particularly limited, but the measuring device 110 is, for example, a computer (one or a plurality of computers) having a CPU, an auxiliary storage device, a main storage device, a network interface, and an input / output interface. Can be configured by In this case, the air flow sensor 1 and the high response flow meter 10 are connected to the input / output interface. Further, the auxiliary storage device stores a program for realizing the functions of the "control unit 111, the data acquisition unit 112, and the airflow sensor characteristic information calculation unit 113". The functions of the "control unit 111, the data acquisition unit 112, and the airflow sensor characteristic information calculation unit 113" are realized by the CPU loading the program into the main storage device and executing the program.

Further, the control unit 111 controls the overall operation of the measuring device 110, receives various settings and inputs from the user, and receives an operation request for the air flow sensor meter characteristic information generation system W1.
The data acquisition unit 112 acquires the measured values (first air flow rate, second air flow rate) measured by each sensor (air flow sensor 1 and high response flow meter 10) at a predetermined measurement timing.

Further, the air flow sensor meter characteristic information calculation unit 113 uses the "second air flow rate" measured by the high response flow meter 10 as the reference flow rate, and uses the reference flow rate and the "first air flow rate" measured by the air flow sensor 1. The transmission function (Gx (s)) of the air flow sensor 1 is calculated. Further, the airflow sensor characteristic information calculation unit 113 generates and stores a regression transfer function (Gy (s)) from the transfer function (Gx (s)).

Next, the procedure of the airflow sensor characteristic information generation process performed by the airflow sensor characteristic information generation system W1 of the first embodiment will be described with reference to FIGS. 1 and 2 to 4 described above.
Here, FIG. 2 is a flowchart showing a procedure of airflow sensor characteristic information generation processing performed by the airflow sensor characteristic information generation system of the first embodiment. FIG. 3 is a schematic diagram showing the input / output relationship of the transmission characteristics of the airflow sensor calculated by the airflow sensor characteristic information generation system of the first embodiment. FIG. 4 is a schematic diagram for explaining a process of fitting and identifying a transfer function to the transmission characteristics of the airflow sensor calculated by the airflow sensor characteristic information generation system of the first embodiment.

As shown in FIG. 2, first, the airflow sensor characteristic information generation system W1 performs the data measurement process (S1).

In this data measurement process (S1), the pressure step response device Z is driven to change the pressure of the pressurized air (fluid) in the pipe 20 in a stepped manner. Specifically, the valve operating device 40 of the pressure step response device Z drives the pressurized air supply device 30 with the first valve 21 "open" and the second valve 22 "closed". The pressurized air is allowed to flow into the pipe 20 for a predetermined time. Further, the valve operating device 40 closes the first valve 21 after a lapse of a predetermined time, and supplies the fluid from the pressurized air supply device 30 between the two valves (first and second valves 21, 22). Confine the pressurized air (fluid). After that, the valve operating device 40 controls the "open / close" state of the second valve 22 to change the pressure of the pressurized air (fluid) in the pipe 20 in a stepwise manner. For example, when the second valve is "open" while the pressurized air is trapped between the two valves (first and second valves 21, 22) of the pipe 20, the downstream side (1st and 2nd valves 21 and 22) of the second valve 22 ( A rapid high-speed air flow occurs in the region (to the right of the direction shown in FIG. 1).

Further, the data acquisition unit 112 of the measuring device 110 is changing the pressure of the pressurized air (fluid) of the pipe 20 in a stepped manner, and the air flow rate in the pipe 20 measured by the air flow sensor 1 (No. 1). 1 air flow rate) and the air flow rate (second air flow rate) in the pipe 20 measured by the high response flow meter 10 are acquired.
The data acquisition unit 112 stores the acquired measurement values (first air flow rate, second air flow rate) in association with each other for each measurement time (for example, a memory (not shown) (auxiliary storage device of the measurement device 110 and main). Storage device).

Next, the airflow sensor characteristic information generation system W1 performs a transfer function calculation process (S2).
In the calculation process (S2) of this transfer function, first, the air flow sensor characteristic information calculation unit 113 of the measuring device 110 uses the air flow rate (second air flow rate) in the pipe 20 measured by the high response flow meter 10 as a reference flow rate. And.
Further, in S2, as shown in FIG. 3, the air flow sensor characteristic information calculation unit 113 uses the reference flow rate (second air flow rate (Q)) as an input value, and the measurement time corresponding to the reference flow rate (second air flow rate). Using the air flow rate (first air flow rate (Q')) measured by the air flow sensor 1 as an output value, a Fourier analysis calculation is performed to calculate the transmission characteristic (Gx'(s)) of the air flow sensor.
In the gain diagram of FIG. 4, an example of the transfer characteristic (Gx'(s)) obtained by the above Fourier analysis calculation is shown.
Further, in S2, the airflow sensor characteristic information calculation unit 112 fits the calculated transfer characteristic (Gx'(s)) with an arbitrary transfer function (Gx (s)), and "Gx'(s) = Gx". (S) ”, the parameters (α, β) of the transfer function (Gx (s)) are identified (see FIG. 4).

なお、エアフロセンサ特性情報算出部１１３は、図示しないメモリ（計測装置１１０の補助記憶装置及び主記憶装置）に、Ｓ２で算出した「伝達特性（Ｇｘ’（ｓ））、伝達関数（Ｇｘ（ｓ））」と、Ｓ３で算出した回帰伝達関数（Ｇｙ（ｓ））に記憶させる。Next, the airflow sensor characteristic information generation system W1 performs a calculation process of the regression transfer function (S3).
In the calculation process (S3) of this regression transfer function, the airflow sensor characteristic information calculation unit 113 of the measuring device 110 uses the transfer function (Gx (s)) calculated in S2 to perform the regression shown in the following (Equation 1). The transfer function (Gy (s)) is calculated.
The "Lowpass filter" has a characteristic that does not interfere with Gx (s) by using a filter with a cutoff set at a higher frequency than the Gx (s) band.

In addition, the airflow sensor characteristic information calculation unit 113 puts the “transmission characteristic (Gx'(s)) and the transfer function (Gx (s)) calculated in S2 into a memory (auxiliary storage device and main storage device of the measuring device 110) (not shown). )) ”, Stored in the regression transfer function (Gy (s)) calculated in S3.

As described above, in the air flow sensor characteristic information generation system W1 of the first embodiment, the pressure step response device Z creates a state in which the flow rate of air (fluid) flowing in the pipe 20 of the pipe 20 changes rapidly. Further, under that state, the flow rate of air flowing through the pipe 20 is measured by each of the "general-purpose air flow sensor 1" and the "high response flow meter 10 having higher responsiveness than the air flow sensor 1". Then, the measuring device 110 uses the air flow rate (second air flow rate) measured by the "high response flow meter 10" as a reference flow rate, and this reference flow rate and the air flow rate measured by the "air flow sensor 1" (first). The regression transfer function of the air flow sensor 1 is calculated using the air flow rate).
Then, by correcting the measured value measured by the air flow sensor 1 using the calculated air flow sensor characteristic information (return transfer function), the air flow rate is substantially the same as that measured by the high response flow meter 10. The value will be obtained (accurate air flow rate can be obtained).
That is, according to the first embodiment, the generally used general-purpose "air flow sensor 1" has the same response as the "high response flow meter 10" such as an ultrasonic flow meter or a lamina flow meter. It can be upgraded to performance (the responsiveness of the airflow sensor 1 can be improved).

<< Second Embodiment >>
Next, the configuration of the airflow sensor characteristic information generation system according to the second embodiment of the present invention will be described with reference to FIGS. 5 to 7.

Here, FIG. 5 is a schematic view showing the configuration of the airflow sensor characteristic information generation system of the second embodiment. Further, FIG. 6 is a flowchart showing a procedure of airflow sensor characteristic information generation processing of the airflow sensor characteristic information generation system of the second embodiment.
Of the configurations of the second embodiment, the same configurations (or equivalent configurations) as those of the first embodiment are designated by the same reference numerals to simplify or omit the description, and are mainly referred to as the first embodiment. Explain the different contents.

As shown in FIG. 5, the airflow sensor characteristic information generation system W2 of the second embodiment is an airflow sensor that measures the flow rate of air flowing into the engine cylinder 11 of the engine E installed on the engine bench (engine test device) B. 1. A high response flow meter 10 that measures the flow rate of air flowing into the engine cylinder 11, and a measuring device 110 that calculates air flow sensor characteristic information (transmission function, regression transmission function) indicating the characteristics of the air flow sensor 1. doing.
In the process of measuring the measured values for calculating the airflow sensor characteristic information (transfer function, regression transfer function) of the engine bench B by each sensor (airflow sensor 1, high response flow meter 10), the throttle response changes. , The air flow rate flowing into the engine cylinder 11 is suddenly changed.

Further, the air flow sensor 1 is installed in the intake pipe (intake pipe) 5 connected to the intake manifold 3 that sends air to the engine cylinder 11, and the air flow rate of the air flowing into the engine E (first air). The flow rate) is measured, and the measured air flow rate (first air flow rate) is transmitted to the measuring device 110.
Further, the high response flow meter 10 is connected to one end of an intake pipe (intake pipe) 5 connected to an intake manifold 3 that sends air to the engine cylinder 11, and the air flow rate of the air flowing into the engine E ( The second air flow rate) is measured, and the measured air flow rate (second air flow rate) is transmitted to the measuring device 110.
In the figure, reference numeral 7 indicates a throttle valve, and reference numeral 9 indicates an exhaust pipe for discharging air from the engine E.

The measuring device 110 receives the measured values (first air flow rate, second air flow rate) transmitted from each sensor (air flow sensor 1, high response flow meter 10), respectively. Further, the control device 110 uses the measured value (second air flow rate) sent from the high response flow meter 10 as the reference flow rate among the received measured values.

Further, the measuring device 110 uses the above reference flow rate (second air flow rate) and the measured value (first air flow rate) acquired from the air flow sensor 1 to obtain a transfer function (Gx (s)) of the air flow sensor 1. Is calculated, and a regression transfer function (Gy (s)) is generated from the transfer function (Gx (s)) and stored. The process of calculating the transfer function (Gx (s)) and the regression transfer function (Gy (s)) is the same as that of the first embodiment described above.

Further, the engine bench B controls the operation of the dynamometer 50 that applies a load to the engine E to be tested, the shaft 53 that connects the rotation shaft of the dynamometer 50 and the rotation shaft of the engine E, and the operation of the dynamometer 50. It includes a dynamo control device 51 and an engine control device 60 that controls the operation of the engine E. The engine control device 60 gives control parameters such as a throttle opening degree and an ignition advance angle to the engine E, controls the open / closed state of the throttle valve 7, and controls the drive of the engine E.
Since the engine bench B uses a well-known technique, detailed description thereof will be omitted. Further, since the engine E to be tested has a well-known configuration, only the part directly related to the airflow sensor characteristic information generation system W2 of the second embodiment is shown in the figure.

Next, the functional configuration of the measuring device 110 constituting the airflow sensor characteristic information generation system W2 of the second embodiment will be described.
The measuring device 110 includes a control unit 111, a data acquisition unit 112, and an air flow sensor characteristic information calculation unit 113.

The control unit 111 controls the overall operation of the measuring device 110 as in the first embodiment described above.

The data acquisition unit 112 drives the engine bench B and causes a steep change in the air flow rate flowing into the engine cylinder 11 due to a change in the throttle response of the engine E. In this state, each sensor (air flow sensor 1, The measured values (first air flow rate, second air flow rate) measured by the high response flow meter 10) are acquired.

The airflow sensor characteristic information calculation unit 113 performs an airflow sensor characteristic information (transfer function (Gx (s)) and a regression transfer function (Gy (s)) indicating the characteristics of the airflow sensor 1 by a calculation procedure substantially the same as that of the first embodiment. )) Is calculated and stored.

Next, the procedure of the airflow sensor characteristic information generation process performed by the airflow sensor characteristic information generation system W2 of the second embodiment will be described with reference to FIGS. 5 and 6.

As shown in FIG. 6, first, the airflow sensor characteristic information generation system W2 performs the data measurement process (S11).
In this data measurement process (S11), the engine cylinder 11 is driven to control the throttle opening of the engine E installed on the engine bench B or the intake valve angle to make a sharp change. The flow rate of air flowing into the engine is changed sharply. Further, the measuring device 110 measures the "air flow rate flowing into the engine E (first air flow rate)" measured by the air flow sensor 1 while the air flow rate flowing into the engine cylinder 11 is suddenly changed. And the "air flow rate flowing into the engine E (second air flow rate)" measured by the high response flow meter 10.
Further, the data acquisition unit 112 stores the acquired measurement values (first air flow rate, second air flow rate) in association with each other for each measurement time (for example, a memory (not shown) (auxiliary storage device of the measurement device 110 and main). Storage device).

Next, the airflow sensor characteristic information generation system W2 performs a transfer function calculation process (S12).
In the calculation process (S12) of this transmission function, the airflow sensor characteristic information calculation unit 113 of the measuring device 110 constituting the airflow sensor characteristic information generation system W2 determines the “air flowing into the engine E” measured by the high response flow meter 10. Air flow rate (second air flow rate) ”is used as the reference flow rate.
Further, in S2, the airflow sensor characteristic information calculation unit 113 uses the reference flow rate (second air flow rate (Q)) as an input value, and the airflow sensor 1 measures the measurement time corresponding to the reference flow rate (second air flow rate). Using the "air flow rate of the air flowing into the engine E (first air flow rate (Q'))" as an output value, a Fourier analysis calculation is performed to calculate the transmission characteristics (Gx'(s)) of the air flow sensor (FIG. 3).
Further, in S12, as in the first embodiment described above, the airflow sensor characteristic information calculation unit 112 fits the calculated transfer characteristic (Gx'(s)) with an arbitrary transfer function (Gx (s)). , The parameters (α, β) of the transfer function (Gx (s)) are identified so that “Gx ′ (s) = Gx (s)”.
The procedure for calculating the transfer function of S12 is the same as that of the first embodiment described above.

Next, the airflow sensor characteristic information generation system W2 performs a calculation process of the regression transfer function (S13).
In the calculation process (S13) of the regression transfer function, the airflow sensor characteristic information calculation unit 113 performs the same process as the first embodiment described above to calculate the regression transfer function (Gy (s)) (described above ((s)). See equation 1)). Further, the airflow sensor characteristic information calculation unit 113 stores the “transmission characteristic (Gx'(s))” calculated in S12 and the transfer function (Gx (s)) in a memory (auxiliary storage device and main storage device of the measuring device 110) (not shown). )) ”, Stored in the regression transfer function (Gy (s)) calculated in S13.

As described above, in the air flow sensor characteristic information generation system W2 of the second embodiment, the engine test device B in which the engine E is installed creates a state in which the flow rate of the air (fluid) flowing into the engine E changes rapidly. ing. In that state, the "high response flow meter (air flow meter such as ultrasonic flow meter, lamina flow meter) 10" has higher responsiveness than the general-purpose products "air flow sensor 1" and "air flow sensor 1". Each of them measures the flow rate of the air (fluid) flowing into the engine E. Then, the measuring device 110 uses the air flow rate (second air flow rate) measured by the "high response flow meter 10" as a reference flow rate, and this reference flow rate and the air flow rate measured by the "air flow sensor 1" (first air flow rate). ) To calculate the regression transfer function of the air flow sensor 1.
Then, by correcting the measured value measured by the air flow sensor 1 using the calculated air flow sensor characteristic information (return transfer function), an air flow rate substantially similar to that measured by the high response flow meter 10 can be obtained. It will be obtained (accurate air flow rate can be obtained).
That is, in the second embodiment as well, as in the first embodiment, the general-purpose "air flow sensor 1" generally used for the engine of an automobile is used as a "high" such as an ultrasonic flow meter or a lamina flow meter. The response performance can be upgraded to the same level as that of the response flow meter 10 ”, and the responsiveness of the air flow sensor 1 can be improved.

<< Engine control system of utilization examples of the first and second embodiments >>
Next, an example of utilizing the airflow sensor characteristic information generated by the airflow sensor characteristic information generation systems W1 and 2 of the first and second embodiments of the present invention will be described with reference to FIG. 7.
Here, FIG. 7 is a schematic diagram for explaining an example of utilization of the airflow sensor characteristic information generated by the airflow sensor characteristic information generation system of the first and second embodiments, and stores the airflow sensor characteristic information. An engine control system having an engine control device is shown.

The illustrated engine control system includes an engine E provided with an airflow sensor 1 and an engine control device (hereinafter referred to as "ECU") 200 for controlling the operation of the engine E, and is mounted on an automobile and used. ..

The ECU 200 controls the operation of the engine E mounted on the automobile, and the engine control unit 201 that controls the operation of the engine E and the airflow sensor characteristic information generation systems W1 and 2 of the first and second embodiments described above are used. It includes a storage unit 203 that stores the generated "airflow sensor characteristic information (return transfer function (Gy (s))) of the airflow sensor 1.

The air flow sensor 1 is installed in the intake pipe (intake pipe) 5 connected to the intake manifold 3 that sends air to the engine cylinder 11, measures the air flow rate of the air flowing into the engine E, and causes the ECU 200 to measure the air flow rate. Send the measured air flow rate.

Further, when the engine control unit 201 of the ECU 200 receives the “air flow rate of the air flowing into the engine E” measured by the air flow sensor 1, the “regression transmission function (Gy (s))” stored in the storage unit 203. By applying the read "return transfer function (Gy (s))" to the received "air flow rate", the "air flow rate of air flowing into the engine E" measured by the air flow sensor 1 is changed to "air flow rate". Corrected to "corrected air flow rate (air flow sensor regression value)".
After that, the engine control unit 201 controls the operation of the engine E by using the “corrected air amount (air flow sensor regression value)”.

The illustrated ECU 200 uses the airflow sensor characteristic information (return transfer function (Gy (s))) of the airflow sensor 1 generated by the airflow sensor characteristic information generation systems W1 and 2 of the first and second embodiments described above. , The air flow sensor 1 measures the air flow rate, and the corrected air flow rate is used to control the operation of the engine E. Is omitted.

In this way, the airflow sensor characteristic information generation systems W1 and 2 of the first and second embodiments of the present invention generate airflow sensor characteristic information indicating the characteristics of the airflow sensor 1, and store the airflow sensor characteristic information in the ECU 200 to respond. The engine can be controlled by the measured value (corrected air flow rate) of the air flow sensor 1 with improved performance.
Therefore, even in an automobile equipped with an engine E equipped with a heat ray type airflow sensor 1, the engine E can be controlled to the optimum operation by configuring the ECU 200 as described above.

Note that FIG. 7 described above illustrates an engine control system that controls an engine E mounted on an automobile, but the present invention is not particularly limited to this. For example, the above-mentioned airflow sensor characteristic information (regression transfer function (Gy (s))) may be used in an engine test apparatus for testing an engine E provided with a heat ray type airflow sensor 1. In this case, the engine control device that controls the drive of the engine E stores the "return transfer function (Gy (s))", and the engine control device uses the regression transfer function (Gy (s)) to airflow. The air flow rate measured by the sensor 1 may be corrected, and the corrected air flow rate obtained may be used to control the operation of the engine E to perform various tests of the engine.

Further, in the above-described embodiments (first and second embodiments), an ultrasonic flow meter or a lamina flow meter is shown as an example of the high response flow meter 10, but the response to fluctuations in the air flow rate is higher than that of the air flow sensor 1. If the value is high (fast), it is applied to the present invention.

For example, the flow rate measuring system described in Japanese Patent Application Laid-Open No. 2020-1134243 (Patent Document 2) filed by the applicant of the present application can also be used for the high response flow meter 10. In this flow rate measurement system, the characteristics (differential pressure sensor characteristic information) of the differential pressure sensor mounted on the laminar flow meter (laminar flow meter) are calculated in advance, and the measured values measured by the laminar flow meter ( The air flow rate (differential pressure measured by the differential pressure sensor) is corrected by the differential pressure sensor characteristic information, and the corrected value is taken as the air flow rate.

Specifically, the laminar flow meter of the flow rate measuring system described in Patent Document 2 described above includes a main body provided with a laminar flow element, a static pressure in an upstream portion of the laminar flow element, and a downstream portion of the laminar flow element. A differential pressure sensor that measures and outputs the differential pressure from the static pressure of the unit is provided.
Further, the differential pressure sensor includes a first connecting pipe that acquires the static pressure in the upstream portion of the laminar flow element, a second connecting pipe that acquires the static pressure in the downstream portion of the laminar flow element, and the first and second connecting pipes. Each is connected and has a sensor unit that measures the differential pressure between the static pressure in the upstream portion and the static pressure in the downstream portion.

Then, the above differential pressure sensor characteristic information is obtained by removing the differential pressure sensor from the lamina flow meter and connecting the air inflow path to the first connecting pipe of the removed differential pressure sensor in the stage before the process of calculating the intake flow rate of the engine. One end of the second connecting pipe of the connected and removed differential pressure sensor is opened to the atmosphere. Further, in the above state, air is allowed to flow into the differential pressure sensor through the air inflow path, the pressure in the air inflow path near the first connecting pipe is measured as the first pressure, and the first is applied to the differential pressure sensor unit. The differential pressure between the pressure of the connecting pipe and the pressure of the second connecting pipe is measured as the second pressure, and the relationship between the first pressure and the second pressure is converted into frequency characteristic information indicated by gain and phase for each frequency. The frequency characteristic information is shown by the transfer function.

Then, when the high response device 10 of the airflow sensor characteristic information generation system W1 and 2 of the present invention is applied to the flow rate measurement system described in Patent Document 2, the differential pressure sensor characteristic calculated in advance is applied to the measurement device 110. Remember the information. Further, a laminar flow meter is used for the high response device 10 of the air flow sensor characteristic information generation systems W1 and 2. Then, when the data acquisition unit 112 acquires the measured value (second air flow rate) measured by the lamina flow meter, the data acquisition unit 112 corrects and obtains the second air flow rate using the stored differential pressure sensor characteristic information. The corrected second air flow rate is used as the reference flow rate. Then, the air flow sensor characteristic information (transfer function (Gx (s), regression transfer function (Gy (s)))) is calculated using the reference flow rate and the first air flow rate measured by the air flow sensor 1.

In the above-described embodiment (first and second embodiments), the heat ray type airflow sensor is used for the airflow sensor 1, but the present invention is not particularly limited to this. A non-heat ray type may be used for the air flow sensor 1. That is, in the air flow sensor characteristic information generation systems W1 and W2 of the present embodiment, those other than the heat ray type can be used as long as they do not have the responsiveness to detect a steep flow rate change.

Next, the measured value of the airflow sensor 1 was actually corrected by using the airflow sensor characteristic information (regression transmission function (Gy (s)) calculated by the airflow sensor characteristic information generation system W1 of the first embodiment of the present invention. The relationship between the regression result (air flow sensor regression value), the value measured by the air flow sensor 1, and the value measured by the high response flow meter 10 will be described with reference to FIG.

Here, FIG. 8 shows a regression value obtained by returning the measured value of the airflow sensor using the airflow sensor characteristic information calculated by the airflow sensor characteristic information generation system of the first embodiment of the present invention, a measured value of the airflow sensor, and a measured value of the airflow sensor. It is a graph which showed the relationship with the reference flow rate which is the measured value of a high response air flow meter.
Note that FIG. 8A is a graph showing the measured values and the regression results of the air flow meter (air flow sensor 1, high response flow meter 10) in the predetermined measurement time zone (0.4 seconds to 2 seconds). FIG. 8B is an enlarged graph showing the measured values and the regression results of a part of the measurement time zones (1.3 seconds to 1.6 seconds) from the graph of FIG. 8A. ..

As shown in the graph of FIG. 8, the airflow sensor regression value obtained by correcting the measured value of the airflow sensor 1 using the airflow sensor characteristic information (return transfer function (Gy (s))) is the measured value of the high response flow meter 10. It can be seen that the value is almost the same as that of a certain reference (reference flow rate).
In this way, by calculating the airflow sensor characteristic information (return transfer function (Gy (s))) of the airflow sensor 1 according to the present embodiment, the general-purpose "airflow sensor 1" can be used as an air flow meter or an ultrasonic flow meter. It was confirmed that the response performance can be upgraded to the same level as that of the "high response flow meter 10" such as the lamina flow meter, and the responsiveness of the air flow sensor 1 can be improved.

W1, W2 ... Airflow sensor characteristic information generation system

1 ... Air flow sensor 10 ... High response flow meter

Z ... Pressure step response device 20 ... Piping 20a ... 1st straight pipe section 20b ... 2nd straight pipe section 21 ... 1st valve 22 ... 2nd valve 30 ... Pressurized air supply device 40 ... Valve operating device

110 ... Measuring device 111 ... Control unit 112 ... Data acquisition unit 113 ... Airflow sensor characteristic information calculation unit

B ... Engine bench 50 ... Dynamometer 51 ... Dynamo control device 53 ... Shaft 60 ... Engine control device

E ... Engine 3 ... Intake manifold 5 ... Intake pipe (intake pipe)
7 ... Throttle valve 9 ... Discharge pipe 11 ... Engine cylinder

Claims (4)

An air flow sensor installed in the intake pipe of an engine installed in an engine test device to measure the flow rate of air flowing into the engine, and a high-response flow meter connected to the intake pipe to measure the flow rate of air flowing into the engine. An airflow sensor characteristic information generation system equipped with a measuring device for calculating airflow sensor characteristic information.
The high response flow meter is a flow meter having a higher response to fluctuations in the air flow rate than the air flow sensor.
The measuring device is the first air flow rate measured by the air flow sensor while the engine test device drives the engine to cause a steep change in the flow rate of the air flowing into the engine. , A data acquisition unit that acquires the second air flow rate measured by the high response flow meter,
A second air flow rate the acquired as a reference flow rate, the air flow sensor characteristics information calculating unit that calculates a regression transfer function of the airflow sensor as the d Afro sensor characteristic information by using the reference flow rate and the first air flow rate the acquired An air flow sensor characteristic information generation system characterized by having. The air flow sensor is a heat ray type air flow sensor.
The high response flowmeter Eafurosen service characteristic information generation system according to claim 1, characterized in that the ultrasonic flowmeter or lamina flow meter. The airflow sensor characteristic information calculation unit uses the reference flow rate as an input value, uses the first air flow rate measured by the airflow sensor corresponding to the reference flow rate as an output value, performs a Fourier analysis calculation, and obtains the transfer characteristics of the airflow sensor. calculated, to calculate a transfer function from the transfer characteristics thus calculated, generated Eafurosen service characteristic information according to claim 1 or 2, characterized in that it consists transfer function to calculate the regression transfer functions system. An engine control system having an engine control device that stores the regression transfer function generated by the airflow sensor characteristic information generation system according to any one of claims 1 to 3 and an engine provided with the airflow sensor. And
The air flow sensor is installed in the intake pipe of the engine, measures the air flow rate flowing into the engine, and transmits the measured air flow rate to the engine control device.
The engine control device acquires the air flow rate measured by the air flow sensor, calculates a corrected air flow rate that corrects the acquired air flow rate by using the stored regression transfer function, and calculates the corrected air flow rate. An engine control system characterized in that the engine is controlled by using the engine.

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