SU1377825A1 - Pneumatic control system - Google Patents

Abstract

The invention relates to a technology for manufacturing automation and can be used in control systems with high demands on the quality of regulation and to the safety of the technological process in the oil refining and chemical industries. The purpose of the invention is to increase the quality of regulation by introducing new elements and connections. This is achieved by the fact that the device has repeaters with a shift of 4 and 5, the first and second signaling devices 2, 3 limit values, the supply channel of the first signaling device 2 is connected with the output c (b

Description

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parameter 1, and the output - with the power supply channel of the second alarm device 3, ka: reset: with the lower channel value of the parameter P (sensor) 6; the reset channel of the second alarm device 3 is connected to the upper channel of the parameter Pj, (sensor ) 7. And the output of the indicator 3 to one of the inputs of the switching relay 8, the other input of which is connected to

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the output of the parameter controller 1, the control chamber is with the disconnection channel of the parameter controller 1, and the output is with the actuator 9. This improves the response of the system to pulsed disturbances and eliminates abrupt changes in the control action during the transition to manual remote control. 1 il.

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The invention relates to instrument making and. can be used in process automation systems in a wide range of changes in driver and disturbing influences ..

The purpose of the invention is to increase the quality of regulation.

The drawing is a schematic diagram of the proposed pneumatic control system.

The system contains a regulator of 1 parameter (of the Start system PRZ.Z type), the first 2 and second 3 limit value alarms, repeaters 4 and 5 with a shift, the channels of the upper RC and the lower Pj of the parameter limit values with setting points 6 and 7, switching relay 8, actuator 9.

The channels of the parameter parameter and the task are connected to the corresponding inputs of controller 1. Channel Parameter, 33 J

Pa connected to the mutually inverse inputs of the detectors 2 and 3, the other inputs of which are connected to the outputs of the repeaters 4 and 5, their inputs connected to the task channel The power channel of the first alarm 2 is connected to the outlets of the controller 8 and the first switching input of the switching relay 8, the reset channel - with the lower channel of the parameter Rc, setpoint 6 output — with the power supply channel of the second detector 3, the reset channel of which is connected to the upper channel of the parameter P (setpoint 7), and the output with the second switched input of the switching relay 8, conductive chamber which is connected with a channel interrupting P regulator 1, while the output - to the actuating mechanism 9 IOM.

The system works as follows.

Preliminary, using repeaters 4 and 5, with a shift, adjust from the boundary of the zone of permissible deviations of the controlled parameter L1 and + (i, H L shifts

repeaters 4 and 5), and in channels 6 and 7 of the setters - the limiting (boundary) values of the output signal P and P "(usually Pg 1.0 and Pg 0.2 kgf / cm).

As long as the adjustable parameter is within the tolerance zone

 - L, Rror P + A2. The top nozzles of the detectors 2 and 3 are open and the signal of the parameter controller is fed to the line of the actuator.

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When the parameter is out of bounds

the zone opens the lower nozzle of the corresponding annunciator 2 or 3 and the actuator 9 is in communication with the channel P ... or

setting device 6 or 7 and moves to one of the extreme positions. Thus, forced relay control, sometimes coinciding with blocking in pre-emergency and emergency situations, is performed outside the tolerance zone. In contrast to the prototype, the proposed device performs forced control not only during deep

perturbations on the load, but also

with significant changes in the task, causing a violation of the conditions

    RP "P P-J 2) In this case, due to the fact that the forced control signal is not remembered when the parameter returns to the allowable zone, the response of the system to impulse races on the load is improved.

In the manual remote control mode (1), the actuator line is switched to the control station setter (not shown), thereby eliminating the possibility of a step change in the control action in this mode, unlike the prototype.

Claims (1)

Invention Formula A pneumatic control system containing a parameter controller connected to the channels of parameter 25 and the task, the actuator, the first and second signaling devices of the of individual values with channels of the lower and upper parameter values, a switching relay, the first switched input of which is connected with the output of the parameter controller, and the output with an actuator, characterized in that, in order to improve the quality of regulation, two repeaters are installed in it the shift, the inputs of which are connected to the reference channel, and the outputs are connected to the first mutually inverted inputs of the signaling devices, the second inputs of which are connected to the parameter channel, the power supply channel of the first signaling device being connected to the output of the steam regulator meter, the reset channel - with the channel of the lower boundary value of the parameter, the output with the channel, the power of the second / detector, the reset channel of which is connected to the channel of the upper boundary value of the parameter, the output - to the second switched input of the switching relay, the control chamber of which is connected to the channel Disable the parameter controller.