JPS624722B2 - - Google Patents

Description

[Detailed description of the invention]

When operating multiple operating devices such as pumps, blowers, injection machines, etc. in parallel, the present invention selects a combination of operation numbers that satisfies the total target value input from the outside, and controls the external circuit. The present invention relates to an operation control device that outputs start commands, stop commands, and operation setting values for each device. Generally, multiple actuators (e.g. the aforementioned pump,
When attempting to achieve a required total target value, such as a total discharge target value, by combining and operating in parallel (blower, injector, etc.), the operation controller must be adjusted to satisfy the total discharge flow rate target value. There are several combinations (defined as driving patterns). Among these combinations, which combination to drive, that is, which driving pattern to drive, is selected based on various conditions. When each controller can be switched between automatic and manual modes individually, for machines in automatic mode, the operator can start and stop those controllers, and set the flow rate for each controller. It may be done individually and arbitrarily.
The operating value (in this case, the discharge flow rate) of the operating device operated in such a manual operation mode is a large amount of disturbance when viewed from a control device whose target value is the total discharge flow rate. Conventionally, the control loop has been greatly disturbed by such disturbance amounts. For example, using an alarm setting device, start the first controller from the target total discharge flow rate, start the second controller,
Starting the first unit, stopping the first unit, stopping the second unit, etc.
In a conventional control device that outputs a signal such as ... and starts or stops an operating device using this signal, the discharge flow rate of a machine that is not in automatic mode is entirely a disturbance amount. Here, a machine that is not in the automatic mode is a machine that is not operated by the operation output from the control device corresponding to the machine, but is operated manually by the operator. Therefore, it was not possible to accurately achieve the target value of the total discharge flow rate. Furthermore, in such conventional devices, even when the maximum rated operating value, that is, the discharge flow rate rated value of each actuator operating in parallel differs from each other, the total discharge flow rate can be accurately determined in order to use only the increase/decrease command for the number of units as the operation output. It was not possible to match the target value. The purpose of the present invention is to input the operating value of a manually operated machine, which is a disturbance amount for the control loop, into the control device in advance, and furthermore, for the machine in automatic mode, even if the maximum rated operating value of the machine is different, To provide an operation control method that predicts and calculates a realizable total operation value in advance from those adjustable operation values and accurately realizes a required total target value. The present invention will be described below with reference to an embodiment shown in the drawings. FIG. 1 is an embodiment of a control device using the method according to the invention. 1 is a control device, which is not shown, but includes a central processing unit (CPU),
Built-in memory, PI/O, etc. This control device 1 controls the total target value of a plurality of operating devices 2 (for example, if the operating device 2 is a pump, the total discharge flow rate target value
Qdem), the combination of operating units that realize
The operating value for each machine, that is, in this case, the distribution value of the discharge flow rate set value is determined. For this purpose, the control device 1 controls each unit of the controller 2 during operation.
Digital input signal 3 that turns ON, digital input signal 4 that turns ON in automatic mode which is the mode switching signal for each machine, and analog signal PV of the actual operating value of each actuator 2 (hereinafter described as actual discharge flow rate).
Enter each. The control device 1 selects the best driving pattern based on these input signals.
In accordance with this selected operation pattern, a start/stop command signal 5 is output to the machine in automatic mode. Contact _A1 is a contact that turns ON when in automatic mode. This start/stop command signal 5 starts or stops the operating device 2 via a general relay sequence circuit and a main circuit 6. On the other hand, for machines in manual mode, the push button switch PBS
When in manual mode, the start/stop command is
Relay sequence circuit through contact _M1 to ON,
A signal is sent to the main circuit 6 to start and stop the controller 2. In addition, the operating value (hereinafter explained as discharge flow rate) setting signal 7 for each operating device 2 is set in the automatic mode.
It is output to the flow rate regulator FC via contact _A2 , which turns ON. On the other hand, the manual flow rate set value SV is a contact that is turned ON when in manual mode from the manual setting device 10.
Output to flow regulator FC via _M2 . The actual discharge flow rate PV of each operating device 2 is inputted to the flow rate regulator FC as a feedback signal, and a manipulated output signal MV is outputted to the flow rate control device NC. This flow rate control device NC adjusts the discharge flow rate q of the operating device 2. The discharge flow rate q of each operating device 2 is connected in parallel through piping 8, and becomes the total discharge flow rate Qtotal. Next, the operation control method according to the present invention will be explained according to the schematic flowchart shown in FIG. (1) Input processing (block 11) The following signals used for the following arithmetic processing are input from the outside. Total discharge flow rate target value Qdem Digital signal 3 that turns ON while each controller is operating. Digital signal 4 that turns on in automatic mode for each controller. Actual discharge flow rate analog signal PV of each actuator From these input signal items, it is possible to determine which actuator is currently in operation, what mode it is being operated in, and what its actual discharge flow rate is. You can keep track of them at all times, and they are stored in memory. (2) Generation of operation pattern (block 12) An operation pattern is a combination of all the units to be operated when multiple controllers are operated in parallel, and if there are n controllers, 2 ⁿ
There are combinations of streets. That is, all these patterns are generated in order. (3) Consideration of manual mode units (block 13) Since units in manual mode are not subject to automatic control by this device, operation patterns that require output of start commands or output of stop commands to these units should be considered. shall be invalid. That is, this is because the current operating state of the machine in manual mode cannot be changed by the control device 1. (4) The controllable range is the total discharge flow rate target value.
Are you satisfied with Qdem? (Block 14) Based on the operation pattern selected in item (3), the range of the total discharge amount that is predicted to be achievable is predicted and calculated using Equations 1 and 2 shown below.

[Table]
These equations 1 and 2 are calculated for a certain operation pattern i, that is, a combination pattern PTN(i) of whether the j-th car is operated or stopped. The first term in { } on the right side of equations 1 and 2 is the range calculation for the machine in automatic mode. The number machine in automatic mode is this control device 1.
Assuming that it is possible to output a constant amount of discharge flow according to the start/stop command and flow rate setting value output from the machine, the upper limit value α _H (j) and lower limit value α _L ( The discharge flow rate can be set from the control device 1 within the range of j). The load factor upper limit value α _H (j) and lower limit value α _L (j) are as follows.
Due to mechanical factors specific to each controller,
This limits the range of load factors and is determined in advance for each operating device. On the other hand, the second term in { } on the right side of equations 1 and 2 is the range calculation for the machine in manual mode. As explained in section (3), for the machine in manual mode, since it is not controlled by the control device 1, the current actual discharge flow rate is assumed to be fixed, and this disturbance amount is determined in advance by the operation pattern i. It is considered that it is included as a bias in the total discharge flow rate. Next, it is determined whether the required total discharge amount target value can be achieved with this driving pattern i, depending on whether the following three equations are satisfied. If satisfied, the pattern is considered valid. R _L (i)≦Qdem<R _H (i) ……Equation 3 Here, Qdem is the total discharge flow rate target value. (5) Judgment of “Is the number of state changes minimum?” (block 15) If multiple patterns remain after the judgments in (1) to (4) above, choose the current operating device pattern from among them. In other words, the one with the least frequency of starting and stopping compared to the current driving pattern is left as the best driving pattern. That is,
As mentioned above, which machine is currently in operation is stored in memory, so the operation pattern based on this is compared with each pattern selected by the above judgment, and the one with the least frequency of starting and stopping is selected. choose. (6) Judgment based on priority order (block 16) When multiple patterns remain even after the judgment in item (5) above, the predetermined priority order for each unit is further operated for each pattern. The driving pattern with the highest priority is determined to be the best pattern. (7) Saving the best driving pattern (block 17) The determinations in (1) to (6) above are performed for all driving patterns. As a result, one pattern remains as the best pattern. Save this pattern. (8) Calculation of discharge flow rate distribution value (block 18) Once the operating pattern is determined, the load factor of the actuator is calculated using the following four formulas. The second term in the numerator on the right side of this equation is the current total actual discharge flow rate of the all-manual mode machine. Then,
The numerator is the total discharge flow rate that should be borne by the automatic mode machine. Moreover, the denominator is the sum of the maximum discharge flow rate rated values of the automatic mode machines operating in this operation pattern. Therefore, α(i) is the load factor of the automatic mode machine being operated. Based on this load factor α(i), the flow rate setting value for each operating device is calculated using the following five formulas. y(j)=α(i)・x(j) ……Equation 5 Load factor α to maximum discharge flow rate rated value x(j) of unit j
The value multiplied by (i) becomes the flow rate setting value y(j) of the j-th machine. (9) Manipulation output (block 19) The best operation pattern and flow rate set value, which are the results of the above calculations, are sent to an external controller via the relay sequence circuit shown in Figure 2, the main circuit 6, the flow rate setting device FC, etc. Output to. To summarize the above method of the present invention, the discharge flow rate of the manual mode operation unit, which is a disturbance amount for the control loop, is taken in advance, and furthermore, for the automatic mode operation unit, even if the maximum discharge flow rate rated value is different, , calculate the range of adjustable discharge flow rate, predict and calculate the realizable total discharge flow rate in advance, and select an operation pattern that minimizes the frequency of starting and stopping. According to this operation pattern, each operating device is started and stopped via an external relay sequence circuit and a main circuit, and a flow rate setting value is provided to the flow rate control device of each operating device. These signals cause each controller to
Individually requested discharge flow rates are achieved, and the total discharge flow rate of the manual mode machine, which is a disturbance amount, is also incorporated into the control loop to achieve the required total discharge flow rate target value. Next, another embodiment of the present invention will be described. Although the flow control device for each operating device has been explained as being attached to all machines, even if it is installed only in some machines and the remaining machines are installed as fixed flow machines, the effects of the present invention can be achieved. remains unchanged.
In addition, in relation to this, we assumed that the load factors of each actuator were the same and the operation was performed at a uniform load factor α(i). Even in this case, the effect of the present invention remains unchanged. The flow control device not only controls the speed of the actuator, but also
It may be controlled by opening degree control of a discharge valve or suction valve, stroke control, or other methods. Furthermore, the effect of the present invention is the same not only in the method of controlling the individual flow rates of each operating device, but also in the case of collective flow rate control in the middle of piping after the discharge flow rates are combined. As described above, according to the present invention, when selecting an operation pattern to achieve the required total target value, the operation value of the manual mode controller included in the pattern, that is, the conventional disturbance amount Since the controllable range of the pattern is obtained by taking in in advance what was previously handled as a pattern, it is possible to obtain an accurate operation control output with respect to the total target value. Moreover, rather than simply controlling the number of units, the operating value for each operating unit is determined individually according to its rated value, so accurate control can be performed even if the capacity of each operating unit is different.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing an example of a facility for implementing the method of the present invention, and FIG. 2 is a flowchart showing an embodiment of the operation control method according to the present invention. 1...Control device, 2...Operator, 3...Digital signal that turns ON during operation for each operator, 4
...Digital signal that turns ON in automatic mode for each operating device, 5...Start and stop command for each operating device, 6... Relay sequence circuit and main circuit, 7
...Flow rate set value signal to each controller, 8...Piping,
Qdem...total target value, PV...actual operating value analog signal of each actuator, _A1 , _A2 ...contact that turns ON when each actuator is in automatic mode, _M1 , _M2 ...each actuator Contact that turns ON when is in manual mode.

Claims (1)

[Claims] 1. When controlling the operation of a combination of a plurality of actuators to satisfy a required total target value, it is possible to determine the operation of the actuator in manual mode from all operation patterns resulting from the combination of the plurality of actuators. Select an operation pattern that does not require starting or stopping, and for each of these selected patterns, set the operating value of the manual mode controller included in that pattern as a bias value, and enable operation of the fully automatic mode controller within this pattern. The upper and lower limits of the controllable range of this pattern are determined from the maximum and minimum values, and a pattern in which the total target value falls between the upper and lower limits of this controllable range is determined as an effective pattern. Characteristic operation control method. 2 When controlling the operation of a combination of multiple controllers to satisfy the required total target value, it is not necessary to start and stop the controller in manual mode from all operation patterns resulting from the combination of multiple controllers. Select an operation pattern, and for each of these selected patterns, use the operating value of the manual mode controller included in that pattern as the bias value, and set the maximum and minimum possible operating values of the fully automatic mode controller within this pattern. Find the upper and lower limits of the controllable range of this pattern from the above, find a pattern in which the total target value falls between the upper and lower limits of this controllable range as an effective pattern, and calculate, for the total target value,
Determine the operating value that all the automatic mode operating devices in this effective pattern should bear, and divide this by the sum of the maximum rated operating values of the fully automatic mode operating devices mentioned above to determine the load factor of the automatic mode operating device. An operation control method characterized in that the operating value of each automatic mode operating device in an effective pattern is determined by multiplying the maximum rated operating value of each automatic mode operating device in the effective pattern.