JPS61125602A - Digital-type adjuster - Google Patents

Abstract

PURPOSE:To avoid an excessive change in a control signal supplied to a controlled system even if an output is switched from a digital type adjuster at the operating side to that at the standby side. CONSTITUTION:A switching signal S3 from a monitor 7 discriminates the PID adjuster at the operating side 11 and that at the standby side 12. The PID arithmetic based on equations 1-4 is executed in said adjuster 11, and a signal S5 is supplied to the controlled system 4. A control amount X is detected by a detector 3 and fed back to said adjusters 11 and 12. The PID adjuster at the operating side 12 estimates the integral arithmetic result of the PID adjuster at the operating side 12 according to equation 5, and the PID arithmetic is executed based on equations 6-9 with the estimated value as an integral initial value. After the prescribed time expires, the integral arithmetic result of the PID adjuster at the operating side 11 is again estimated, and the PID arithmetic is executed with the estimated value as an integral arithmetic value. After wards said sequence is interacted by the prescribed interval. Thus outputs of both PID adjusters go to approximately the same values.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an improvement in a digital adjustment device that configures a multiple redundant system by a plurality of digital controllers including an integral factor 1γ.

[Conventional technology]

In recent years, digitization has progressed in the field of 11-node controllers including integral operations, and digital PID controllers using small computers called microcomputers or minicomputers have been developed and put into practical use.

Generally, the reliability of the digital PID device is increased by constructing a multiple redundant system.

Figure 2 shows two digital PIOs! FIG. 2 is a block diagram showing a conventional digital IPID adjustment device that uses a single node to configure a double redundant system. For example, the operating 11 PID controller 1 and the standby PID are configured by a microcomputer! 1
The moderator 2 inputs the detection 11X1 of the control amount It is determined by calculation. The power of both PID regulators 1.2 is such that the one selected by the changeover switch 6 is supplied to the 111111 target 4. Further, the input and output signals of both PID controllers 1 and 2 are provided to a monitor 7. Then, the monitor 7 determines whether both the regulators 1.2 are normal or abnormal, and if both the PfD regulators 1.2 are normal, the operating side PID with high priority! 11 verse 1 is selected,
If one is abnormal, it is a normal PID! A switching control signal for selecting the m1 moderator is sent to the changeover switch 6, and an alarm signal is issued to an alarm (not shown),
The operator is notified of any abnormalities in the controller.

Like this PID! A double redundant system is constructed using 1 ID and 21 nodes, and the detector 4. A changeover switch 6 and a monitor 7 are provided, and both of the above PID! A highly reliable digital PID system can be obtained by configuring the system so that the reliability is much higher than when the single section unit 1.2 is used alone.

(Problem to be Solved by the Invention) However, as described above, when a multiple redundant system is constructed using a plurality of digital regulators including integral calculations, the control deviation calculated by each digital regulator is If the values are different, the output of the regulator may swing out to the maximum or minimum due to the integral operation. That is, the control deviation e1 (
t> and the control deviation e2 determined by the standby PID controller 2
(t) may differ due to the influence of noise, a shift in data acquisition timing, etc. Then, Ill
The control I width deviation t(t) of the operating side PID11 node 1 included in the III loop eventually becomes zero, but lll1
The control deviation e2 (t) of the standby side PID controller 2 that is not included in the loop No. 11 does not become zero. Therefore, the standby PID controller 2 integrates the control deviation e2 (t) many times, and the output eventually reaches the maximum or minimum value.

In this state, the operating side PIDKlli! When an abnormality occurs in the controller 1, the changeover switch 6 is switched by the monitor 7 and the standby PID controller 2 is included in the III'ta loop, so the control signal supplied to the controlled object 3 changes excessively. Therefore, @III x for the controlled object 3 fluctuates greatly, causing a problem that stable all (Ill) cannot be performed.

Therefore, in the present invention, even if an abnormality occurs in the active digital controller and it is switched to the standby digital controller, the control signal supplied to the controlled object will not change excessively, and the control amount for the controlled object will be large. It is an object of the present invention to provide a digital adjustment device that can always perform stable control without fear of fluctuation.

(Means for Solving the Problems) The present invention is characterized by taking the following measures to solve the above problems and achieve the objectives.
Estimating the integral calculation result of the active digital controller included in the control loop and performing the integral calculation by at least one standby digital controller, and performing the integral calculation using the estimated integral calculation result as an initial value, The operating status of the digital 11-section controller on the operating side and the digital controller on the standby side is monitored by a monitor, and if an abnormality occurs in the digital regulator on the operating side, the digital controller on the standby side is immediately replaced. It is characterized in that the regulator output is switched by a switching means so as to be included in the 11111 loop.

[Effect]

By taking such measures, the output of the standby digital controller is always approximately equal to the output of the active digital controller, so that the output from the active digital controller to the standby digital controller is Even if the output is switched to , no excessive change will occur in the control signal supplied to the controlled object.

[Embodiment] FIG. 1 is a block diagram showing the configuration of a double redundant type digital PID adjustment device as an embodiment of the present invention.

Note that the same parts as in FIG. 2 are given the same reference numerals, and detailed explanations will be omitted. In this embodiment, an active side PIDv4 moderator 11 and a standby IIIPID configured by a microcomputer are used.
The regulator 12 receives a feedback signal S1 . In addition to the setting signal S2 indicating the set value x2 supplied from the terminal 5, a switching control signal S3 outputted from the monitor 7 is input.

In addition, the output signal S4 of the samurai side PID control fi12 is input to the working side PID controller 11, and the waiting 1111111
1PIO51! ii to vessel 12: 1. tllllllP I
The output signal S5 of the Din device 11 is input. The above operating side PID! In the 11-section unit 11, one digital type PID calculation is performed, and the standby side PID controller 12
Then, at predetermined time intervals, the operation 1 [integral operation I in the IPio controller 11] is estimated, the initial value of the integral operation is changed to the value of the estimated integral operation result, and then the digital PID operation is performed. It becomes.

The digital PID operation in the operating III PID regulator 11 is as follows: Un -kp (en +SA +DA) where the regulator output is U, the integral operation result is S, the differential operation result is R, and the control@deviation is e.
−(1)Sa −(T/T+)Σe i
−(2)On = (To, /T)<en
-en-s) ・13)e, q -X 2n
-X IrL·14).

In each of the above equations, kP is the gain, T is the sampling period, T+ is the integration time, To is the differentiation time, and n is the value at n sampling times.

Here, according to the above formula (1) and (3), Sn = (1/kp)Lln + (To/T)e
a-+[(T+To)/T]ea-(5)
is obtained. Therefore, in the standby side PID controller 12, the active side PID! The output U taken in from the II node 11 and l1III calculated by the standby side PID controller 12
By performing the calculation shown in equation (5) above using The calculation is done.

That is, at the time of n sampling, the PID adjustment 1612 is the integral calculation result S of the operating side PID controller 11.
Assuming that A is estimated, the PID calculation in the standby PID controller 12 after the (n+1) sampling time is Uwps-kp (ewM+swM+Dwm)=・(0
5wM-8a + (T/T+) and e w
+ □17) Ilshin Dwy-(To/T) (ewM-eWA-t)...
a ews-X2M-X 1wM-(
9). Note that in each of the above equations, W indicates the Samurai Akebono side, and M indicates the sampling point of (n+1) or more.

In this example configured as described above, the operating side PID controllers 11 and 11j open PID! by the switching control signal s3 from the monitor 7. 1-section device 12 is determined. Then, <PID calculation is performed in the operating side PIDI moderator 11 based on the above-mentioned equations (1) to (4), and the output signal S5 of this operating side regulator 11 is supplied to the controlled object 4 via the changeover switch '6. The control amount X for the controlled object 4 is detected by the detector 3, and this detection &IX1 is the operating side PID
controller 11 and Samurai (feedback to the front side PID controller 12. On the other hand, the Samurai tilRIIPID controller 12
In operation 111PID! The integral calculation result of the one-node unit 11 is estimated based on the above equation (5), and the estimated integral F
14 calculation result is used as the initial integration value, <PID calculation is performed based on the above formulas (a to (9)), and when a predetermined time has elapsed, the integration calculation result of the operating side PID 11 node 11 is estimated again,
PID calculation is performed using this as the initial value of integration, and this is repeated at predetermined intervals thereafter. By doing so, the output of the standby side PID regulator 12 becomes approximately equal to the output of the active side PIO regulator 11.

Therefore, an abnormality in the operating side PID regulator 11 is detected by the monitor 7, and the changeover switch 6 is switched in accordance with the switching control signal S3 outputted from the FM monitor 7, and the standby side PID adjustment is performed in the llll1lI loop. Even if the controller 12 is included, there is no risk that the control signal supplied to the controlled object 4 will change excessively.

In this way, the control amount X for the controlled object 4 does not vary greatly, making stable control possible.

Note that the present invention is not limited to the above embodiments.

For example, in the above embodiment, a double redundant system is constructed using two PID controllers, but the same effect can be obtained even if 311 or more are used to construct a triple or higher multiple redundant system.

Further, in the above embodiment, a case was shown in which a PID regulator was used, but other regulators including an integral operation, such as a P regulator, a PD regulator, etc.
It is also applicable to regulators, P+y4m devices, etc. It goes without saying that various other modifications can be made without departing from the gist of the present invention.

(Effects of the Invention) As described in detail above, the present invention estimates the integral calculation result of the active vJ@digital type lit moderator included in the control loop and performs the integral calculation by at least one standby side digital type controller, Integral calculations are performed using this estimated integral performance result as an initial value, and the operating states of the working side digital controller and the standby digital controller are monitored by a monitor, and the operating status of the working side digital controller is monitored. When an abnormality occurs in the controller, the switching means switches the regulator output so that the standby digital regulator is included in the control loop.

Therefore, according to the present invention, the standby digital type v
Since the output of the A node is approximately equal to the output of the active digital controller, even if an abnormality occurs in the active digital controller and the switch is switched to the standby digital controller, the output will not be supplied to the controlled object. The control signal will not change excessively, and the control amount for the controlled object will not fluctuate greatly.
It is possible to provide a digital adjustment device that allows stable control at all times.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 2 is a block diagram showing a conventional example. 1.11... Working side PID controller, 2.12... Standby III PID regulator, 3... Detector, 4... tl
lII [l Target, 5...terminal, 6...changeover switch, 7...monitor.

Claims (1)

[Claims] An active digital type controller included in the control loop and performing integral calculations; and at least one standby digital type controller that estimates the integral calculation results in the active digital type controller and performs integral calculations using the integral calculation results as an initial value. a controller; a monitor that monitors the operating states of the standby digital regulator and the active digital regulator;
The monitor further comprises switching means for switching the regulator output so that the standby digital regulator is included in the control loop when an abnormality occurs in the operating digital regulator. A digital adjustment device.