JPH0156401B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for controlling various processes such as air conditioners and production equipment.

[Prior art] When controlling various processes, various sensors detect control quantities such as flow rate, pressure, temperature, humidity, etc., and these detected quantities are sampled at regular intervals. Averaging a predetermined number of N pieces of data obtained by Control is becoming common.

[Problem that the invention seeks to solve]

However, because N pieces of data are always averaged and control is repeated according to the average value, sudden or temporary changes in the control amount are eliminated, and the control situation becomes stable. Fluctuations in the control amount in response to changes in the control amount are also averaged out, causing a problem in which control responsiveness is delayed and followability of the control situation is degraded.

[Means for solving problems]

In order to solve the above-mentioned problem, the present invention is constructed by the following means.

That is, in the above control method, the predetermined number N
Find the average value m from data from the present to the past for a plurality of n pieces smaller than n pieces, and k
The average value m ₂ of n pieces of data from the past to the past is calculated, and when the absolute value of the difference between these average values m ₁ and m ₂ is greater than a certain value, it is assumed that a sudden change has occurred and the transmission of the trigger pulse is stopped. , from this point on, when the current and previous data change direction is the same and the absolute value of the difference between these data is less than a predetermined value, or when the change direction of these data becomes opposite, this point The average value m ₃ of a plurality of pieces of data from 1 to the past is calculated, and a trigger pulse is sent out to instruct control based on this average value m ₃ .

[Effect]

Therefore, the average value m ₁ obtained by averaging the n pieces of data closest to the present, and the past data n
If the difference from the average value _m2 exceeds a certain value, it is determined that there is a sudden change in the control amount, and as a result, the sending of the trigger pulse is stopped, and from now on, The change state is stabilized when the current and previous data change direction is the same and the absolute value of the difference between them is less than a predetermined value, or when the change direction of each data becomes opposite. Then, average l data from this point to the past to find the average value m ₃ .
A trigger pulse is sent to command control based on this, and sudden or temporary changes are ignored, and once this change stabilizes, control based on the average value _m3 is immediately performed. , the responsiveness of control to fluctuations in the control amount is improved.

〔Example〕

Hereinafter, details of the present invention will be explained with reference to figures showing examples.

Figure 2 is a block diagram of the control device, which includes a processor such as a microprocessor (hereinafter referred to as CPU).
1, fixed memory (hereinafter referred to as ROM) 2,
Variable memory (hereinafter referred to as RAM) 3 and interfaces (hereinafter referred to as I/F) 4 ₁ to 4 ₄ are arranged around it, and these are connected by a bus bar, and I/F 4 ₁ receives detection signals from various sensors, etc. The output is given as input data D _i , and from the I/F 4 ₂ , a control signal for each device to be controlled, such as a refrigerator or a pump, is sent out as output data D ₀ .

In addition, a higher-level device such as a central control unit is connected to the I/F 4 ₃ via a transmission path 5, and data signals are sent and received via the I/F 4 ₃ , and basic control data given from the higher-level device is transmitted and received. At the same time, data indicating the control status is sent for monitoring purposes.The I/F _{4 4} is equipped with terminal equipment (hereinafter referred to as TE) 6 such as a display such as a cathode ray tube display and a keyboard. By operating the TE 6, data is stored and updated in the RAM 3, and the status of these and control status is displayed by the TE 6.

Here, the CPU 1 executes naming in the ROM 2, samples the input data D _i via the I/F 4 ₁ as a detection amount at a constant cycle, stores this data sequentially in the RAM 3, and stores it in a predetermined number N of data. A calculation is performed to find the average value, and upon completion of this, a trigger pulse is sent out, and this is used as an opportunity to perform a control calculation, and the resulting output data _D0 is sent out, and the control based on this is repeated. However, in addition to this, the calculations and controls shown in FIG. 3 are also performed, and when these are executed, the calculations and controls are performed while accessing the necessary data to the RAM 3.

That is, FIG. 3 shows a sampling situation and an average value calculation situation when, for example, pressure P is the detected quantity. Pressure P is sampled at a constant period _t0 , and normally the average value of a predetermined number of N pieces of data is calculated. When this is completed, a trigger pulse is sent out at time _t1 , but in addition, if _t2 is the current time, the relationship N>n is satisfied, and n pulses are sent from the present to the past. Average value based on data of
In addition to finding m ₁ , find the average value m ₂ of past n data from k past data from the present, and if the absolute value of the difference between each average value m ₁ and m ₂ is greater than a certain value C, there is a sudden change. It is determined that this has occurred, and subsequent trigger pulse transmission is stopped accordingly.

However, as well as continuing sampling, it is necessary to judge whether the current data has increased or decreased compared to the previous data, and to repeat calculations to find the difference between the current and previous data. When the direction of change of each data is the same and the absolute value of the difference between these data is less than the predetermined value d, or when the direction of change of each of these data is opposite, the transient change is stabilized. If this point is t ₃ , then l from point t ₃ to the past
The average value m ₃ of the data is determined and control is performed based on this, a trigger pulse is sent out at time t ₃ , and the control situation is determined by a control calculation based on the average value m ₃ .

FIG. 1 is a flowchart of the control situation mainly between time points t ₁ and _{t 3} in FIG. ?” 101 is (YES), “OND determination according to changes in the number of operating units and control amount” 102 is performed, and a standby time OND is determined to stop the next start and stop control until the control amount is stabilized. In addition, there is a “startup averaging prohibition flag set” 103 that prohibits average value calculation using sampling data while the control amount is changing.
Do this.

When step 101 is N (NO), step
In response to Y of 104 "OND progress?", "inhibition flag reset" 105 is performed in correspondence with step 103.

Next, by determining the number of operating units as described above, if there is an operating unit that is in operation and will stop, “ON→CFF?1”
11 becomes Y, and “according to changes in the number of operating units and control amount”
Waiting time for stopping the next start and stop control until the controlled variable is stabilized by OFD decision "112"
After determining the OFD, "stop averaging prohibition flag set" 113 is performed in the same manner as described above.

Also, if step 111 is N, step 114
In response to "Y of OFD progress?", "prohibition flag reset" 115 is performed in correspondence with step 113.

Next, depending on the flags in steps 103 and 113,
“Averaging prohibited? Check 121, this is N
If so, perform the input data “sampling D _i ” 123 according to the Y of the constant period “t ₀ elapsed?” 122, check the “changing?” 124 of the input data using the flag described later, Perform each average value "m ₁ , m ₂ operation" 131 in FIG. 3 according to N, and determine "|m ₁ - m ₂ | C?" 132,
If the absolute value of the difference between m ₁ and m ₂ is greater than or equal to the constant value C, the result will be Y, and a sudden change will occur. Therefore, "change flag set" 133 corresponding to step 124 is performed. After that, "change sign flag set" 134 is performed to indicate whether the sign of the difference between m ₁ and _{m 2} is positive or negative, and the value is set to RAM3.
"Data storage" 135 of the sampling data in step 123 is performed.

On the other hand, the flag in step 133 causes step 124 to be
If is Y, the current data D _i and the previous data
D _i-1 , calculate e _i =D _i −D _i-1 ”141, and calculate “e _i
Are the signs of +e _i-1 the same? ``142, and then determine whether e _i is less than or equal to the predetermined value d according to Y of this _.
|d? ” 143. If this is N, the process is still changing, and the process moves to step 135.

On the other hand, step 142 is N, and e _i and e _i-1
When the sign of the step becomes opposite or
When 143 becomes Y, the change has stabilized, so
After performing the average value "m ₃ calculation" 151 in FIG. 3, the "change flag reset" 152 is performed corresponding to step 133.

Furthermore, if step 132 is N, it is a stable state and the process moves to step 135 according to N in "Number of samples = N?" 161, whereas if this is Y, the maximum Specify whether or not to exclude values and minimum values.
MIN cut? ”162, it is judged according to the contents of RAM3, and if this is Y, “MAX・MIN
Step 162
In accordance with N, "N average value calculation" 164 is performed, and the average value obtained in steps 163, 164 or 151 is calculated by "average value → control calculation" 171.
Store it in RAM3 as data for control calculation,
“Send trigger pulse” 172 and press “EXIT”
The program then moves to a control calculation routine via these routines, and repeats step 101 and subsequent steps.

Therefore, sudden or temporary changes in the control amount are ignored for control purposes, but if a sudden change occurs and stabilizes, control according to the average value m ₃ is immediately performed, Realizes quick response and stable control.

However, the numbers n, k, and l may be determined depending on the conditions, and the detected amounts may be based on various physical quantities depending on the purpose.

Moreover, the equipment to be controlled can be arbitrarily selected according to the control amount, and can be applied not only to control of the number of operating units but also to capacity control, etc.

In addition, the configuration shown in Figure 2 can be selected depending on the situation. etc. are arbitrary, and the present invention can be freely modified in various ways.

〔Effect of the invention〕

As is clear from the above explanation, according to the present invention, sudden or temporary changes in the detected amount are ignored, but as soon as the sudden change situation stabilizes, control is performed based on the average value. The responsiveness of the sensor is improved, stable control is performed, and remarkable effects can be obtained in various controls based on various detected amounts.

[Brief explanation of drawings]

The figures show an embodiment of the present invention; FIG. 1 is a flowchart of a control situation, FIG. 2 is a block diagram of a control device, and FIG. 3 is a diagram showing a sampling situation and an average value calculation situation. 1...CPU (processor), 2...ROM (fixed memory), 3...RAM (variable memory), 4 ₁ to 4 ₄ ...
...I/F (interface), P...pressure (detected amount), _m1 to _m3 ...average value, C...constant value, d...
...Predetermined value.

Claims (1)

[Claims] 1. Sampling the detected amount at a fixed period,
In a control method that averages a plurality of N pieces of data obtained in this way and sends out a trigger pulse that commands control based on the average value, the average of a plurality of N pieces of data from the present to the past that is less than the N pieces of data is averaged. In addition to finding the value m ₁ , calculate the average value of the n pieces of data from the past k pieces to the past.
m ₂ is determined, and when the absolute value of the difference between these average values m ₁ and m ₂ is greater than a certain value, the sending of the trigger pulse is stopped, and from then on, the current and previous data are changed in the same direction and When the absolute value of the difference between each of these data becomes less than a predetermined value, or when the direction of change of each of these data becomes opposite, calculate the average value m ₃ of a plurality of l pieces of data from that point in time to the past, A control method characterized by transmitting a trigger pulse for instructing control based on the average value _m3 .