RU2023282C1 - Device for adjusting relation of discharges of solutions of components - Google Patents

Abstract

FIELD: devices for adjusting relations of components of fluid medium. SUBSTANCE: device has central control unit which has the second pulse generator 12 connected in series with coincidence element 16, reversible counter 11, frequency multiplier 9. The second input of multiplier 9 is connected with output of the first pulse generator 8, output of multiplier 9 is connected with inputs of channels for adjusting discharges of liquids through corresponding signal delay units 24. The first inputs of channels are connected with the first inputs of the first OR gate 10. Output of OR gate 10 is connected with the second input of reversible counter 11, with the second input of the second OR gate 15, with input of pulse former 13 and with the second input of trigger 14. The third inputs of OR gate 15 are connected with the second outputs of the channels, and three channels (n channels are available as well) for adjusting discharge of relation 1′, 1″, 1″′ have setting unit 2 connected in series with the first comparison unit 3, actuating detector 4, flow meter 5, the second comparison unit 6. The second input of comparison unit 6 is connected with output of setting unit 2, the first output of unit 6 is connected with the first output of adjusting channel, and the second output is connected with the second output of adjusting channel. Input of any setting unit 2 is connected with input of corresponding adjusting channel. Any adjusting channel has multiplication unit 18, unit 19 for fixing changes in concentration and concentration detector 17, which are brought into the unit newly. Central unit 7 has three dividers 20′, 20″, 20″′ brought newly, three signal delay units 24′, 24″, 24″′, unit 21 for selecting maximal value, switch 22, three adders 23′, 23″, 23″′, timer 25, the third OR gate 26. EFFECT: improved precision; improved reliability of operation. 4 dwg

Description

 The invention relates to devices for controlling the ratio of components of the current environment and can be used in various industries.

 Currently, with continuous adjustment of the ratio of liquid components, devices are used that consist of a control unit, flow control channels for each of the components, control units for the flow range of the components [1].

 In this device, a performance-determining signal from the central control unit is fed directly to the units for setting the channels for controlling the flow of components in which it is distributed in proportion to the content of each component in the mixture. From the outputs of the job blocks, the control signals are sent to the comparison blocks of the respective control loops, to the second inputs of which the actual flow rates from the flow meters come. Control actions from the comparison blocks go directly to the executive bodies. If one of the flow rates goes out of the range, then the range control units give an appropriate alarm, which can be used to limit the overall performance. Most components come in the form of solutions.

 When switching from one concentration to another, the device does not take into account the location (remoteness) of the executive organs (IO) from the point of displacement of the components. In the case of different remoteness of the IO, a noticeable violation of the ratio is observed, which during the operation of the control system can cause an oscillatory mode, leading to a decrease in the accuracy of regulation of the ratio of component costs.

 Known devices for regulating the ratio of flow rates of liquids that change the performance depending on the acceptable ranges of operation of their elements, not taking into account the concentration of components [2, 3].

 These devices also include a central control unit, flow control channels, each of which contains a task unit, a comparison unit, a flow meter, an actuator, and a unit for determining the performance range. In practice, quite often situations arise of reducing the receipt of a component or group of components, changes in the pressure of liquids in the supply pipelines, etc. This leads to the need to change performance by simultaneously affecting the executive bodies while maintaining a predetermined ratio of liquid flow rates. But these devices do not take into account the transport delay of each control channel, which leads to a violation of the given mixture composition.

 Closest to the proposed one is a device for regulating the ratio of liquid flow rates [4], comprising a central control unit, a first pulse generator, a second pulse generator connected in series, a second coincidence element, a counter and a frequency multiplier, as well as a pulse generator, trigger, and a second OR element connected by the output to the second input of the coincidence element, channels for regulating the flow ratio, for example three, each of which contains the last They are connected to the reference unit, the first comparison unit, the actuator of the flowmeter and, the flowmeter, as well as the second comparison unit, the first input connected to the output of the task unit, the first output with the first output of the control channel, the second output with the second output of the control channel, input each task unit is connected to the input of the corresponding control channel, the first outputs of which are connected to the inputs of the first OR element, the output connected to the second input of the reversible counter, the second input of the second element AND LI, with the input of the driver and with the second input of the trigger, the third inputs of the second OR element are connected to the second outputs of the control channels, the frequency multiplier, the second input connected to the output of the second pulse generator.

 In the known device there are no elements that take into account transport lag, which reduces the accuracy of regulation of a given ratio of components, especially when the concentration changes.

 The purpose of the invention is to increase the accuracy of regulation of the ratio of components by taking into account the transport delay.

 In FIG. 1 shows a block diagram of a device for controlling the ratio of liquid flow rates.

 The device contains three channels 1 ', 1' ', 1' '' of flow control (in the drawing only the scheme of the first control channel is indicated in detail: 2 ', 3', 4 ', 5', etc.), each of which consists from a task unit 2, a first comparison unit 3, an actuator 4, a flowmeter 5, a second comparison unit 6, the central control unit 7 consists of a first pulse generator 8, a frequency multiplier 9, a first OR element 10, a reverse counter 11, a second pulse generator, 12, pulse shaper 13, trigger 14, second element OR 15, element 16 matches Eden.

 In addition, a sensor 17 of the concentration of the component in the solution, a multiplication unit 18, a concentration change recording unit 19, and two additional outputs are introduced into each control channel: 3rd — signal from the flow sensor 5; 4th - the signal from the block 19 fixation.

 The voltage dividers 20 ', 20' ', 20' '', the maximum selection unit 21, the switch 22, the adders 23 ', 23' ', 23' '', the blocks 24 ', 24' ', 24 are introduced into the central control unit 7 '' 'signal delay.

 The outputs of the signal delay units are the output of the central control unit 7 and are connected to the inputs of the corresponding control channel.

 Block 7 also contains a timer 25 and a third element OR 26.

 In FIG. 2 is a functional block diagram of a concentration change recording unit 19. Pos. 27, a filter, or any other signal delay element, pos. 28 - comparator (type 554 CA1).

 In FIG. 3 is a block diagram of a signal delay unit 24.

 In block 24, the received delay time for each channel is entered on the information inputs in the reverse counter 29, for example, 133 IE7, K155 IE7.

 As soon as the difference in the number of given pulses and received is equal to zero, pulses will appear at the output of element And 30, since a resolving pulse appeared from the output of the reverse counter 1.

 In FIG. 4 is a functional diagram of a maximum selection unit 21, where A, B, C, are input information signals; Al, Vl, Sl - logical signals, or control switching signals; 31 - adder; 32 - threshold element; 33 - switch.

 For example, of the three signals A, B, C, the second signal B is the maximum. In this case, a logical unit Vl is generated, which commutes the second information input B with the output of block 21. Thus, block 21 implements the function of selecting the input with the maximum signal.

 The device operates as follows.

 Channels 1 ', 1' ', 1' '' operate using the feedback principle. With an increase in both the frequency that sets the productivity generated by the central unit 7, and with an increase in the setpoints of expenditures on the units 2 ', 2' ', 2' '' of the task, the comparison units 3 ', 3' ', 3' '' increase their output signals which, acting on the actuators 4 ', 4' ', 4' '', increase the flow rate of the liquid through the flow meters 5 ', 5' ', 5' '', so that the input signals of the blocks 3 ', 3' ' and 3 '' 'comparisons of each channel 1', 1 '', 1 '' 'were equal. With a decrease in both the frequency that sets the performance and the flow rate settings of channels 1 ', 1' ', 1' '', the change of tasks in the opposite direction is worked out.

 When searching for performance, commands are used that are generated by comparison units 6 ', 6' 'and 6' '', which act on elements 10-16 of the central unit 7, by which performance is changed in the right direction. These commands provide information on the maximum possible performance for specific flow / differential pressure ratios.

 If the fluid flow rate in at least one channel 1 ', 1' 'or 1' '' will deviate from the reference determined by the input signal of the corresponding reference block 2, 2 '', and 2 '' 'above the pre-established boundary of the zone of permissible values to a large or smaller side, then the command from the output of the second OR element 15 opens the coincidence element 16 and through the last pulses from the generator 12 arrive at the first frequency input of the reverse counter 11. The coincidence element 16 will be open if at least one input of the second OR element 15 will be present team.

 In the established mode, after entering the device at maximum performance, which is determined by the pulse repetition rate of the first pulse generator 8, the logical units are recorded in all discharges in the reverse counter 11 both at the output of the frequency multiplier 9 and also at the output of the signal delay blocks 24 ', 24' 'and 24' '', the pulse repetition rate is equal to the corresponding signal of the first pulse generator 8, there are no commands from the first and second outputs of the second comparison blocks 6 ', 6' 'and 6' ''.

 It should be noted that the appearance of a signal at the first output of the control channel 1 ', 1' 'and 1' '' requires a decrease in performance, and the appearance of a signal at the second output requires an increase in performance. The signals to the first and second output of channels 1 ', 1' 'and 1' '' come from blocks 6 ', 6' 'and 6' '', respectively.

 When the receipt of a component decreases, a command passes through the first element of OR 10, which, acting on the second control input, puts the reversing counter 11 into subtraction mode and at the outputs of its discharges the code begins to decrease, thereby decreasing the performance frequency at the output of the frequency multiplier 9 , and after the delay time of the signal delay, determined for each channel in blocks 23, the corresponding signals appear at the output of blocks 24 ', 24' 'and 24' '', which are fed to the input of each control channel.

 Therefore, the decrease in the output signal of the task units 2 ', 2' 'and 2' '' will not occur simultaneously, although new values of the flow rates of the components of the mixing point are reached at the same time (in Fig. 1, the mixing point is not shown). If the performance decreases below a certain level, when the arrival of a component that was not enough is sufficient to restore the given ratio, the output command from the first output of the channel disappears, the reverse counter 11 through the first element OR 10 will again work in the addition mode.

, τ″=

, τ″′=

.The net delay time for each channel is determined in the dividers 20 ', 20''and20''' as follows
τ ′ =

, τ ″ =

, τ ″ ′ =

.

 In block 21 of the comparison, the maximum delay time is selected, i.e.

τ _max = {τ ′, τ ″, τ ″ ′}
After selecting the maximum delay time τ _max at the output of block 21, the corresponding logical unit (command) is generated, by which the output of the division block, where τ = τ _max , is connected to the first input of adders 23 and the signal corresponding to τ = τ _max also arrives at the information input of timer 25. At the output of the adders, difference signals are generated: τ _max - τ '; τ _max -τ''; t _max -τ'''
These signals are fed to the first input of each delay unit of signal 24, respectively, thus setting the delay time for each channel.

The inclusion of blocks 24 delay the signal and the timer 25 is carried out by the signal from the output of the OR element 26, and the shutdown of the blocks 24 is carried out by the signal "Reset" generated at the output of the timer 25 with the expiration of time τ _max . Then the signals from the output of the adders 23 ', 23''and23''' are fed to the inputs of the corresponding channel without delay.

 In the control channel at the output of the multiplication unit 18, a value equal to 100 is formed of the concentration of the component. At the output of the concentration change recording unit 19, a concentration change start signal is generated, by which delay units 24 and a timer 25 are turned on.

Claims (1)

 DEVICE FOR REGULATING THE RELATIONSHIP OF COSTS OF COMPONENT SOLUTIONS, including a central control unit, a first pulse generator containing a first OR element, a second pulse generator connected in series, a second coincidence element, a purity counter and a purity multiplier, as well as a pulse shaper, a trigger, a second OR element connected in series connected by the output to the second input of the coincidence element, and flow control channels, each of which contains series-connected units to the job, the first comparison unit, the Executive body of the flowmeter and flowmeter, as well as the second comparison unit, the first input connected to the output of the task unit, the first output to the first output of the control channel, the second output to the second output of the control channel, the input of the task unit is connected to the input of the corresponding control channel, and the first outputs of the control channels are connected to the inputs of the first OR element, the output connected to the second input of the reverse counter, the second input of the second OR element, with the input pulse generator and with the second trigger input, the group of inputs of the second OR element is connected respectively to the second outputs of the control channels, a frequency multiplier connected by the second input to the output of the second pulse generator, characterized in that, in order to improve the accuracy of regulation of the ratio of components by taking into account transport delay in each flow control channel, a multiplication unit, a unit for fixing the concentration change, and a component concentration sensor in the solution are introduced, and in the central the control unit has three voltage dividers, a maximum selection unit, a switch, three adders, a timer, a third OR element and three signal delay units, the output of each of which is connected to the input of the corresponding control channel, the first information inputs of each signal delay unit are connected to the output of the corresponding adder , the second information inputs of the signal delay blocks are connected to the output of the frequency multiplier, the trigger inputs are connected to the output of the third OR element connected to the timer enable input, the output of which ohm is connected to the “Reset” input of each signal delay unit, the timer information input and the first inputs of each adder are connected to the output of the switch, the second inputs of each adder are connected to the outputs of the respective dividers, the information inputs of the maximum selection unit and the switch are connected to the outputs of each divider, the control input of the switch is connected to the output of the maximum selection unit, in each voltage divider, the value of the pipeline volume from the installation location of the actuator is entered at the first input rgana to the solution displacement zone, the second input of each voltage divider is connected to the third output of the corresponding flow control channel, the fourth output of each flow control channel is connected to the corresponding input of the third OR element, in each flow control channel the input multiplication unit is connected to the flowmeter output and to the sensor output the concentration of the component in the solution, the output of the flowmeter is also connected to the third output of the control channel, the output of the multiplication unit is connected to the second input of the primary comparator and a second input of the second comparator unit, and a concentration sensor output component through the fixing unit concentration change connected to the fourth output of the corresponding channel regulation costs.

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