JPH09120302A - Pid control unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the unit which can conduct a PID control test without waiting for a user program and/or an external device to be completed. SOLUTION: This unit is equipped with an input part 2 which inputs an input signal from the external device 1, a memory which stores a set parameter and PID data, an arithmetic processing part 4 which performs arithmetic operation on the basis of feedback data controlling the external device 1 and the parameter and PID data and outputs an arithmetic signal, and an output part 5 which inputs the arithmetic signal and outputs an output signal to the external device 1, and is connected to a programmable controller 6, thereby performing feedback control over the external device 1 by a user program 61. In this case, the parameter is provided with a flag for selecting the execution or stop of the PID control test.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a PID control unit for feedback controlling an external device.

[0002]

2. Description of the Related Art An external device is provided with a PID (Proportional Integrated) based on information from a sensor for detecting pressure, temperature, flow rate, etc. provided in the external device.
There is a PID control unit as a device for performing feedback control by and differential control. This PID control unit is used integrally with a programmable controller.

As a conventional PID control unit of this type, there is one having a structure shown in FIG. This includes an input unit 2 that receives an input signal from the external device 1, a memory 3 that stores parameters having setting values and PID data, and feedback data of a signal from the input unit 2 that controls the external device 1. An arithmetic processing unit 4 that performs arithmetic operation based on the parameters and PID data and outputs an arithmetic signal, and an output unit 5 that takes in the arithmetic signal and outputs the output signal to the external device 1.
And are connected to the programmable controller 6. However, this can be changed by the user program 61 provided in the programmable controller 6.
The external device 1 is feedback-controlled.

[0004]

[Problems to be Solved by the Invention] The above-mentioned conventional PI
In the D control unit, a signal from a sensor that detects pressure, temperature, flow rate, etc. provided in the external device 1 is input to the input unit 2, and the feedback data of the signal from the input unit 2 and the memory 3 are stored. The external device 1 can be normally feedback-controlled based on the parameters and the PID data.

However, the PID control test could not be executed until the user program 61 for operating the PID control unit and the external device 1 as the PID controlled device were completed.

The present invention has been made in view of the above circumstances, and its object is to provide a user program and / or
Another object is to provide a PID control unit that can execute a PID control test without waiting for completion of an external device.

[0007]

In order to solve the above-mentioned problems, according to a first aspect of the present invention, an input section for receiving an input signal from an external device, a parameter having a set value and PID data are stored. A memory, an arithmetic processing unit that arithmetically operates based on feedback data for controlling an external device, a parameter, and PID data and outputs an arithmetic signal, and an output unit that receives the arithmetic signal and outputs the output signal to the external device. In a PID control unit that is connected to a programmable controller and feedback-controls an external device according to a user program, the parameter is provided with a flag for selectively operating or stopping a PID control test.

According to a second aspect of the present invention, in the first aspect, an area for storing the feedback data and the operation data of the operation signal is provided in the memory.

According to a third aspect of the present invention, in the first aspect, the parameter switches the input means of the PID data to an external input from the user program or a personal computer after the operation of executing the flag. It is configured to have one set value.

According to a fourth aspect of the present invention, in the first aspect, the parameter is set such that, after the flag is executed, the input mode of the feedback data is an actual input from the external device or a device other than the external device. The configuration has a second setting value for switching to virtual input.

According to a fifth aspect, in the fourth aspect, the parameter has a third set value for switching the input means of the virtual input to an external input from the user program or the personal computer. I am doing it.

According to a sixth aspect of the present invention, in the first aspect, the data transfer means for outputting the data in the memory to the programmable controller is provided.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. The members having basically the same functions are designated by the same reference numerals as those in the conventional example.

Reference numeral 1 denotes an external device, which is feedback-controlled by PID control in a machine tool, robot, or the like, and is provided with a sensor for detecting pressure, temperature, flow rate, etc., which is a feedback signal from the sensor and is an analog signal. It is outputting an input signal that is a signal.

Reference numeral 2 denotes an input section, which is composed of an A / D converter or the like, which takes in an analog signal from the external device 1 as an input signal, converts it into a digital signal, and outputs the first feedback data 36a.

Reference numeral 3 denotes a memory, which is a parameter 31 provided with a flag for selecting whether to execute or stop the test of the PID operation, and first to third parameters having first to third set values of 1 or 0, respectively. 32, 33, and 34. Further, an area 35 for storing PID data 35a composed of a proportional constant, a derivative time, an integration time, etc., an area 36 for storing the first feedback data 36a or the second feedback data 36b which is virtual data, and an arithmetic processing unit described later. 4 and an area 37 for storing the calculation data 37a of the calculation signal output from No. 4 of FIG.

Reference numeral 4 denotes an arithmetic processing unit, which comprises a microcomputer or the like, and the first feedback data 36a from the input unit 2 or the second feedback data 36 stored in the memory 3.
b and the PID data 35a stored in the memory 3 to perform an operation and output an operation signal to the output unit 5 described later, and output operation data 37a of the operation signal to the memory 3.

An output unit 5 is composed of a D / A converter or the like, takes in the operation signal from the operation processing unit 4, converts the digital signal into an analog signal, and outputs the output signal to the external device 1.

Reference numeral 7 is a data transfer means, which takes in the PID data 35a, the first or second feedback data 36a, 36b, and the operation data 37a stored in the memory 3, and transfers the data to the programmable controller 6.

The programmable controller 6 having the user program 61 is connected to the data transfer means 7 and the personal computer 8 having the display screen 81 by the I / O bus. The operation of this is shown in the flowchart of FIG. It will be described based on. Initially, the flag of the parameter 31 is in a stopped state. In this state, the external device 1 can be feedback-controlled with the same function as the conventional one.

In step # 1, either execution or stop of the flag-provided parameter 31 is selected. At this time, the test of the PID operation is executed when it is executed, and similarly, the first to third parameters are executed. 32, 33, 3
One of the first to third setting values of 4 or 1 is selected and input from the personal computer 8.

When the first set value of the parameter 32 is 1 in step # 2, the process proceeds to step # 3, and the PID operation such as proportional constant, differential time, integration time, etc. is controlled in the area 35 of the memory 3 for storing the PID data. PID data 3
5a is input from the personal computer 8 via the programmable controller 6 and the data transfer means 7 so that the PID data 35a can be shared. Also,
When the first set value is 0, the process proceeds to step # 4, and the PID data 35a is input to the area 35 of the memory 3 from the user program 61 provided in the programmable controller 6 via the data transfer means 7.

In step # 5, when the second set value of the parameter 33 is 0, the process proceeds to step # 6, in which the input mode of the feedback data required for PID control actually operates the external device 1. It becomes the actual input. The external device 1 is operated by using the forced output function for forcibly operating the external device 1 provided in the programmable controller 6, and the external device 1 is operated by the input unit 2
The first feedback data 36 a is transmitted via the calculation processing unit 4 and the feedback data storage area 36 of the memory 3.
Is input to

When the second set value of the parameter 33 is 1, the feedback data input mode is the external device 1
It becomes a virtual input that is input without operating. At this time, P
Feedback data for ID control becomes virtual data, and the second feedback data 36b indicates a value that is virtually set over time. And
Go to next step # 7.

In step # 7, when the third set value of the parameter 34 is 1, the process proceeds to step # 8, and the second feedback data 36b which is virtual data is sent from the personal computer 8 to the feedback data storage area 3
Enter in 6. Further, the third set value of the parameter 33 is 0
If so, proceed to step # 9. The second feedback data 36b, which is virtual data, is input from the user program 61 provided in the programmable controller 6 to the feedback data storage area 36 via the data transfer means 7 by executing the user program 61 only once. To do.

In step # 10, the parameter 31
If the flag of No. is execution, the arithmetic processing unit 4 controls the PID operation stored in the memory 3 to the PID data 35a.
Similarly, the second data stored in the memory 3 and virtually input
The calculation is started based on the feedback data 36b or the first feedback data 36a input by the actual input, and the PID operation test is executed. If the flag of the parameter 31 is stopped, the state returns to the initial state.

In step # 11, the personal computer 8 stores the PID data 35 stored in the memory 3.
a, the first feedback data 36a or the second feedback data 36b, and the calculation data 37a are fetched and displayed graphically on the display screen 81.

In such a PID control unit, since the parameter 31 in the memory 3 is provided with the flag as described above, when the flag selects the PID control test execution operation, the external device 1 Operation and /
Alternatively, without executing the user program 61, the arithmetic processing unit 4 performs an arithmetic operation based on the first feedback data 36a or the second feedback data 36b and the PID data, outputs the arithmetic result as arithmetic data, and performs feedback control. An efficient PID control test can be executed without waiting for completion of the external device 1 and its related device and / or the user program 61.

Since the areas 36 and 37 for storing the first feedback data 36a or the second feedback data 36b and the operation data 37a are provided in the memory 3, the memory 3 can also be used as the memory 3 storing the PID data 35a. Since it is not necessary to install, the cost is low.

Further, after the flag execution operation, the input means of the PID data 35a can be switched and selected by the first set value of the parameter 32, so the user program 61
User program 61 with high accuracy when
Even if the user program 61 is not completed, the PID can be obtained by external input from the personal computer 8.
The data 35a can be input.

After the flag execution operation, the input mode is switched according to the second set value of the parameter 33 to change the first mode.
Alternatively, since the second feedback data 36a and 36b can be selected, when the external device 1 is completed, the first feedback data 3 can be input by the highly accurate actual input from the external device 1.
The second feedback data 36b can be input to the memory 3 by the virtual input 6a to the arithmetic processing unit 4 and the memory 3 even when the external device 1 is not completed.

Since the input means of virtual input can be switched and selected by the third set value of the parameter 34,
The second feedback data 36b can be input to the memory 3 by the highly accurate user program 61 when the user program 61 is completed, and by external input from the personal computer 8 even when the user program 61 is not completed.

Since the data transfer means 7 for outputting the data in the memory 3 to the programmable controller 6 is provided, the PID data 35a stored in the memory 3 and
The first or second feedback data 36a, 36b,
The calculation data 37a is read out and displayed on the display screen 81.
Therefore, it can be displayed graphically and monitored and evaluated on a personal computer.

In this embodiment, the data transfer means 7
However, when the programmable controller is provided with a data transfer function, it may not be provided and is not limited.

[0035]

According to the first aspect of the present invention, the parameter in the memory is provided with the flag. Therefore, when the flag selects the execution operation of the PID control test, the operation of the external device and / or the user program is executed. Without executing the above, the arithmetic processing unit performs an arithmetic operation based on the feedback data and the PID data, outputs the arithmetic result as arithmetic data, and does not wait for the completion of the external device for feedback control and / or the user program. Efficient PID
Can perform control tests.

In addition to the effect of the first aspect, the second aspect provides the area for storing the feedback data and the operation data in the memory, so that it can be used also as the memory for storing the PID data, and a new memory is provided. Since it is not necessary to install, the cost is low.

According to the third aspect, in addition to the effect of the first aspect, the user program can be selected by switching the input means of the PID data according to the first setting value of the parameter after the flag execution operation. When completed, it is a highly accurate user program, and even when the user program is not completed, PID data can be input to the memory by external input from a personal computer.

According to the fourth aspect, in addition to the effect of the first aspect, since the input mode can be switched and the feedback data can be selected by the second set value of the parameter after the flag execution operation, the external device can When it is completed, feedback data can be input to the arithmetic processing unit and the memory by highly accurate actual input from an external device, and even when the external device is not completed, virtual data can be input to the memory as virtual input.

According to the fifth aspect, in addition to the effect of the fourth aspect, the third set value of the parameter allows
Since the input means of virtual input can be switched and selected, a highly accurate user program can be used when the user program is completed, and feedback data can be stored in the memory by external input from the personal computer even when the user program is not completed. You can enter.

According to the sixth aspect, in addition to the effect of the first aspect, the data transfer means for outputting the data in the memory to the programmable controller is provided.
The PID data, the feedback data, and the operation data stored in the memory can be read out and displayed graphically on a display screen, and can be monitored and evaluated by a personal computer.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a configuration diagram of a memory of the above.

FIG. 3 is a flowchart of the same operation as above.

FIG. 4 is a configuration diagram showing a conventional example.

[Explanation of symbols]

 1 External Device 2 Input Unit 3 Memory 31 Parameter with Flag 32 Parameter with First Setting Value 33 Parameter with Second Setting Value 34 Parameter with Third Setting Value 35 PID Data Storage Area 35a PID Data 36 Feedback data storage area 36a First feedback data 36b Second feedback data 37 Data storage area for operation signal 37a Operation data 4 Operation processing section 5 Output section 6 Programmable controller 61 User program 7 Data transfer means

Claims (6)

[Claims] 1. An input unit for receiving an input signal from an external device, a memory storing a parameter having a set value and PID data, a feedback data for controlling the external device, and an operation based on the parameter and the PID data. A PID control unit that includes an arithmetic processing unit that outputs an arithmetic signal and an output unit that takes in the arithmetic signal and outputs the output signal to an external device, is connected to a programmable controller, and feedback-controls the external device by a user program, The PID control unit, wherein the parameter is provided with a flag for selectively performing execution or stop of the PID control test. 2. The PID control unit according to claim 1, wherein an area for storing the feedback data and the operation data of the operation signal is provided in the memory. 3. The parameter has a first set value for switching the input means of the PID data to an external input from the user program or a personal computer after the flag execution operation.
The PID control unit described. 4. The parameter has a second set value for switching the input mode of the feedback data to an actual input from the external device or a virtual input from a device other than the external device after the operation of executing the flag. The PID control unit according to claim 1. 5. The PID control unit according to claim 4, wherein the parameter has a third set value for switching the input means of the virtual input to an external input from the user program or the personal computer. 6. The PID control unit according to claim 1, further comprising data transfer means for outputting data in the memory to the programmable controller.