JP2001147838A - Method for controlling open loop and closed loop of process - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for controlling the open loop/closed loop of a process for certainly reading a function program with prescribed frequency in an easy and simple method. SOLUTION: In this method for controlling the open loop and closed loop of a process using a control program divided into a plurality of function programs (E, F, G, and H) processed in a real time with prescribed frequency, at least one counter (ZE, ZF, ZG, and ZH) counts after the processing of the function programs (E, F, G, and H), and increases the count value only the one. In this case, the count value is searched at regular intervals.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for controlling an open loop / closed loop of a process, and more particularly, to a method divided into a plurality of function programs which are processed in real time and are each processed at a predetermined frequency. The present invention relates to a method and an apparatus for controlling the open / closed loop of a process using a control program.

[0002]

2. Description of the Related Art A conventional open-loop / closed-loop control method and apparatus for a process are disclosed, for example, in German Offenlegungsschrift
It is known from E195500957A1. The above publication discloses a fuel injection control device for an internal combustion engine in which a control program is executed in real time. This control program is divided into a plurality of functional programs (tasks) with priorities.
It is read at a predetermined interval and at a predetermined frequency. The control device is a microcomputer, a write / read memory (R
AM), a fixed value memory (EPROM), and a nonvolatile write / read memory (EEPROM).

The control program controls the giving of the calculation time of the processor, adjusts all execution function programs, and permits quasi-parallel processing of a plurality of function programs (multitasking). In this way, the control program is designed so that, for example, a program being processed (during calculation) can be interrupted at any time and a functional program for performing more important (higher priority) process processing can be started. At this time, the interrupted function program is continued from the point where it was interrupted by the control program after the high-priority function program ends.

Such a processing method is described in “Preemptive
Scheduling (Preemptive Sched
uling) or "Preemptive Multitasking"
ng) ".

As described above, the method of controlling the open / closed loop of the process by the control program can quickly respond to a predetermined phenomenon, and is particularly suitable for a real-time system (that is, a predetermined control within a predetermined time limit). Control system that executes the process).

[0006]

However, in the open-loop control / closed-loop control method of the above process, there is a problem that the function program is not always read out at a predetermined frequency.

Accordingly, an object of the present invention is to provide a new and improved open-loop control / closed-loop control method of a process and an apparatus thereof, which enable a function program to be reliably read out at a predetermined frequency by a simple and easy method. Is to do.

[0008]

In order to solve the above-mentioned problems, the invention according to claim 1 uses a control program which is processed in real time and is divided into a plurality of function programs which are each processed at a predetermined frequency. And controlling the process in an open-loop / closed-loop manner, wherein at least one counter counts after processing the function program and increments the count value by one, and the count value is checked at predetermined intervals. , An open loop control / closed loop control method of a process is provided.

In the present invention, one or more counters newly count only when the function program has been completely processed. This counter may be provided with a common counter for one or more functional programs. This count value is determined at regular intervals, and when it is determined that the count value is different from the target value by comparing with a preset target value, one or more function programs corresponding to the counter are requested. It can be estimated that they were not read out at the specified frequency. If the count value is different from the target value, it is possible to take a measure according to the count value. That is, when the function program is not processed with sufficient frequency, the function program can be processed with higher frequency by setting a higher priority to the function program, for example. After examining each count value, the counter may continue counting, or the count value may be reset.

According to a second aspect of the present invention, the counter is provided for each function program, and the counter counts after processing of a dependent function program. Since a dedicated counter is provided for each function program,
The frequency read for each functional program can be known. As a result, the actual frequency at which each function program of the control program is processed can be monitored accurately and reliably.

According to another aspect of the present invention, the monitoring function program (monitoring task) is read by monitoring the count value by a monitoring function program read at a predetermined frequency. In this case, the other function program being executed is interrupted, and is continued after the monitoring function program has been completely processed. This ensures that the monitoring function program is actually processed at a predetermined frequency. At this time, it is preferable that the highest priority is set for the monitoring function program.

Further, if the actual processing frequency of the monitoring function program is monitored by a watchdog, the control program permits “preemptive multitasking”. If not, it can be monitored whether or not the monitoring function program is actually being processed at a predetermined frequency. That is,
After processing of the monitoring function program, the monitoring function program generates a quitting signal. The watchdog can monitor that the quitting signal has not been generated without the monitoring function program being read (or processed). The watchdog is formed as a timed device, and notifies the sequence control of the control program that a quitting signal is not generated within a predetermined time by, for example, an interrupt signal.

According to a fifth aspect of the present invention, a drive system is used for sequence-controlling the control program, and the watchdog is executed independently of the sequence control of the drive system. With such a configuration, the watchdog is not affected by a malfunction or failure of the drive system, so that the monitoring function program can be reliably monitored under any circumstances.

It is preferable that the monitoring function program is configured to monitor whether the count value is within at least one predetermined frequency window.

It is preferable that the frequency window is provided in the control sequence program. further,
Since the upper threshold value and the lower threshold value of the frequency window are individually determined for each control sequence program, it is possible to set a threshold value according to each control program.

According to the present invention, the upper threshold value and the lower threshold value of the frequency window are determined by the sequence control of the control program. Since the threshold value changes in accordance with the driving state of the open / closed loop controlled process, the threshold value for the driving state of the open / closed loop controlled process can be adaptively adapted. Also, the upper threshold and / or lower threshold of the frequency window can be turned off as needed. During this threshold off period, the count value can exceed the threshold value and deviate from the frequency window, so that no error report or interruption signal is provided.

In order to solve the above-mentioned problem, an open loop of a process using a control program which is executed in real time and divided into function programs which are each processed at a predetermined frequency is provided. A control / closed loop control device, wherein the control device is a control / closed loop control device.
An open-loop / closed-loop control of a process is provided, comprising means for performing the method according to any one of the preceding claims.

According to the present invention, an open-loop control / closed-loop control device for a process for executing the method according to any one of claims 1 to 8 can be provided.

[0019]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
In the following description and the accompanying drawings, components having the same functions and configurations are denoted by the same reference numerals, and redundant description will be omitted.

(First Embodiment) Hereinafter, FIGS. 1 and 2
The first embodiment will be described based on FIG. FIG. 1 is a block diagram illustrating a configuration of a control device according to the present embodiment.

First, as shown in FIG. 1, a fuel injection control device 10 for an internal combustion engine includes a microcomputer 11, a write / read memory (RAM) 12, and a fixed value memory (EP).
ROM) 13, nonvolatile write / read memory (EEP)
(ROM) 22, an input / output unit 14, a time pulse counter 23, and the like.

The controller 10 is connected to an engine temperature sensor 15, an intake air temperature sensor 16, a throttle valve potentiometer 17, an oxygen sensor 18, and an electromagnetic injection valve 21. A signal input 19 is supplied from the ignition control device to the fuel injection control device 10, and the rotation speed and the crankshaft angle are calculated based on the signal. Another input 20 is coupled to the ignition lock.

The function of the fuel injection control device 10 will be described below. That is, the fuel injection controller 10 processes the applied input signal and calculates the injection time as a measure of the amount of injected fuel. Further, the control device 10 outputs an injection pulse for an injection time calculated in advance according to the rotation speed and the crankshaft angle. The exact functioning of such a fuel injection control device 10 is described in the book "Electric Vehicle Equipment for Otto Engines /
Auto Electronics (Auto Elektrik)
/ Autoelektronik am Ottom
otor) ", VDI Publishing, 1987, No. 258-2.
Known as described on page 68.

In order to realize the fuel injection control device 10, a complicated control program divided into a series of a plurality of function programs (tasks) is required. Such a functional program is divided and formed so as to include the program part of the control program according to the purpose. Alternatively, it can be divided into functional programs from the viewpoint of the sequence. That is, if there is a program part that must be processed inside the fixed time raster, a plurality of different time rasters are used.

Further, there is a program part which must be processed in a predetermined driving state or in response to an external or internal phenomenon such as program start, program end, full load drive, idling drive, warm-up operation, etc. I do.

Furthermore, the predetermined program part is processed inside a fixed angle raster according to the crankshaft angle.
Normally, all program parts processed within the same time / angle raster are combined into one functional program. For example, an interrupt generated periodically by hardware, for example, every millisecond.
The time pulse counter 23, which is incremented in the service routine, can read out the function program in a fixed time raster. In the interrupt service routine, the actual count value of the time pulse counter checks whether a new function program is activated.

By associating each function program with a priority indicating the importance of the processing of the function program, the reading of the function program can be effectively adjusted. A drive system is used to control the sequence of the control program (that is, to manage the processing of each function program). Such a drive system uses the corresponding program to determine which function program is to be processed by the microcomputer at a preset time.

As shown in FIG. 2, the control device 10
It has counters ZE, ZF, ZG, ZH corresponding to the function programs E, F, G, H of each control device 10. The counters ZE, ZF, ZG, ZH are incremented after the processing of the attached function programs E, F, G, H, and the count values are monitored at regular intervals. Thus, the function programs E, F, G, and H, which are always read at a predetermined frequency, can be reliably read at a predetermined frequency.

A part of the program sequence of the control program corresponds to, for example, four different function programs E, F, G and H as shown in FIG. The function program E having the lower priority 0 is a fixed time raster, and is processed only when the urgent function program is not processed. The function program F of the priority 1 is processed every 100 milliseconds. The control program G of priority 2 is processed inside a fixed angle raster with a crankshaft angle of 180 °. The highest priority 3 function program H is processed every 10 milliseconds on a fixed time raster.

In the program sequence shown in FIG. 2, in order to control the sequence, a drive system is used in which individual function programs can be interrupted at any arbitrary point in time in response to a processing request of a high-priority function program. Is done. Such sequence control is referred to as “preemptive
Multitasking ". For example, at time t1, the function program E is interrupted, and the processing of the function program H is started. At time t2, the processing of the function program H ends.

Next, the processing of the function program E is continued from the place where it was interrupted. The locations where each function program is interrupted are as shown in FIG. All function programs are further interrupted by interrupt requests generated by interrupt service routines (not shown).

At time t0, the count value is read, and
Set to 0. After the processing of the function program H, the counter ZH is incremented by 1, for example, at times t2, t6, t9 and t12. Similarly, for example, the counter ZE is incremented by one at time t13. At regular intervals, the values of the counters ZE, ZF, ZG, ZH are checked by the monitoring function program. In the example shown in FIG. 2, the count value is checked, for example, at time points 10 and t14. Next, the counter is set to 0, and counting is started again.

The monitoring sequence program checks whether or not the values of the counters ZE, ZF, ZG, ZH are inside the frequency windows respectively corresponding to the sequence programs E, F, G, H. The upper threshold value and the lower threshold value of the frequency window are set in advance in each function program as unique values through sequence control of a control program. The upper and lower thresholds of the frequency window can be changed according to the operating state of the internal combustion engine. In the operating state of the processing of the internal combustion engine, the upper threshold or the lower threshold of the frequency window can be turned off as required.

Whether or not the monitoring function program is actually processed at a set frequency is checked by using a watchdog. Since the watchdog is executed separately from the sequence control of the drive system, it is operated independently of the malfunction or failure of the drive system.

While the preferred embodiment according to the present invention has been described above, the present invention is not limited to such a configuration.
Those skilled in the art can envisage various modified examples and modified examples within the scope of the technical idea described in the claims, and those modified examples and modified examples are also included in the technical scope of the present invention. It is understood to be included in.

[0036]

One or more counters will only count further if the functional program has been completely processed. This count value is determined at regular intervals, and when it is determined that the count value is different from the target value by comparing with a preset target value, one or more function programs corresponding to the counter are requested. It can be estimated that they were not read out at the specified frequency.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of a control device according to a first embodiment.

FIG. 2 is a flowchart illustrating a control sequence according to the first embodiment.

[Explanation of symbols]

 Reference Signs List 10 fuel injection control device 11 microcomputer 12 write / read memory (RAM) 13 fixed value memory (EPROM) 14 input / output unit 15 engine temperature sensor 16 intake temperature sensor 17 throttle valve potentiometer 18 oxygen sensor 19 signal input 21 electromagnetic injection valve 22 Non-volatile write / read memory (EEPROM) 23 Time pulse counter

Claims (9)

[Claims] 1. A method for performing open-loop control / closed-loop control of a process using a control program that is processed in real time and is divided into a plurality of function programs that are each processed at a predetermined frequency, wherein at least one counter Counting after the processing of the function program, incrementing the count value by one, and checking the count value at a predetermined interval. 2. The apparatus according to claim 1, wherein said counter is provided for each function program, and said counter counts after processing of a dependent function program.
4. The open-loop control / closed-loop control method of the process according to 1. 3. The method according to claim 1, wherein the count value is monitored by a monitoring function program read at a predetermined frequency. 4. The method according to claim 3, wherein an actual processing frequency of the monitoring function program is monitored by a watchdog. 5. The system according to claim 4, wherein a drive system is used to sequence the control program, and the watchdog is executed independently of the sequence control of the drive system. 4. The open-loop control / closed-loop control method of the process according to 1. 6. The monitoring function program according to claim 3, wherein said monitoring function program monitors whether said count value is within at least one predetermined frequency window. An open-loop control / closed-loop control method of the process described in the paragraph. 7. The method according to claim 6, wherein the frequency window is provided in the control sequence program. 8. The method according to claim 6, wherein an upper threshold value and a lower threshold value of the frequency window are determined by sequence control of the control program. 9. An open-loop control / closed-loop control device for a process using a control program which is executed in real time and is divided into function programs which are each processed at a predetermined frequency, wherein the control device comprises: An open-loop / closed-loop control device for a process, characterized in that it comprises means for performing the method according to any one of claims 1 to 8.