SU1100606A1 - Multi-channel control - Google Patents

Abstract

MULTICHANNEL REGULATOR,. containing a block of circulating devices, connected by the first input to the output of the block of setting values, the second input through the block of measurements and transformations to the output of the block of sensors. the third input — with the output of the regulator device; the remaining inputs — with the outputs of the corresponding correction devices, the first output through the separation unit during the measurement and control processes — with the input of the regulating device, and analog value accumulators connected by the first outputs with the inputs of the corresponding actuators, and the second outputs with appropriate corrective devices, characterized in that, in order to improve the accuracy and speed of the regus tor, it additionally storing registers were established, connected (Led entrances with the corresponding outputs of the block of blocking devices, and outputs - with the inputs of the corresponding analog value accumulators. W /. I-G O5 o O:

Description

The invention relates to automatic regulation and can be used in the automation of technological processes containing low-inertia control objects and requiring simultaneous control of a large number of parameters (for example, in the automatic heat regulation system of an open-hearth furnace, which needs to maintain the load by controlling the flow rates of gas, fuel oil and air, with the time constant of the flow contours under these conditions being 3-5 s and the time constant evatelnyh elements in plastic products production systems with 3-5) are also equal. A multichannel regulator of technological processes is known, containing n control channels with channel storage units, a summing unit, connected to an amplifier with RC circuits at the input and in the feedback circuit, which is connected to the channel storage units through a channel switch, an additional capacitor and three groups of switches, through two of which to the input of the summation of n; its block is connected to the outputs of the channel storage blocks and the amplifier vsod, and one of the plates of the additional condensate Pa is connected to one of the output terminals of the amplifier, and the second plate through the closing contact of the third contact group is connected to the common fault, and the capacitor of the feedback feedback circuit is connected to the common bus through the break contact and in this device the channel memory at the moment of closing the contacts of all switch groups related to this channel. The formation of the updated regulatory action occurs in the next cycle. With a high rate of change of the controlled parameter, the value of the regulating action between two consecutive stocks can be significantly different from each other. A disadvantage of the known device is its low accuracy and poor quality of control when controlling objects with fast processes. A multichannel regulator is also known that contains a block of devices that are connected to a switch, a block of control variables, through measurement and conversion blocks with the outputs of the first accumulators of analog signals and inputs of actuators, second corrective devices and second accumulators of analog values connected to block overrun devices, and the inputs and outputs of the corrective devices are connected to the corresponding outputs and inputs of the second analog value drives, the inputs and outputs of the switch they are connected respectively with the transponder and the second accumulators of analog values 2. A disadvantage of this device is its low accuracy and control quality. The closest in technical essence to the present invention is a multichannel regulator containing. block of circulating devices connected by the first input to the output of the setpoint block, the second input through the measurement and conversion unit to the output of the sensor unit, the third input to the output of the regulating device, the remaining inputs to the outputs of the corresponding corrective devices, the first output through the time-separation unit measurement and control processes - with the input of the regulating device, and the remaining outputs through the corresponding drives of analog quantities - with the inputs of the corresponding executive fur terminals, the second outputs of the accumulators of analog quantities are connected to the inputs of the corresponding correction devices. However, the scope of such a regulator is limited to control objects with sufficiently large time constants (on the order of hundreds and thousands of seconds). The impossibility of using this device to automate low-inertia objects with constant times of the order of units and tens of seconds is due to the fact that the change in the controlled parameter that occurs in such objects under the influence of perturbations occurs quite quickly, and the change in the regulating effect that compensates for these disturbances, can only be performed for the control object that is currently connected to the controller. Therefore, for the time during which the control object is disconnected from the controller, changes in the controlled parameter occurring in it under the influence of perturbations can be significant. This leads to a decrease in the quality of regulation when controlling low-inertia objects. Thus, the disadvantages of the known controller are the low accuracy and speed when controlling low-inertia objects. The purpose of the invention is to increase the accuracy and speed of the controller. This goal is achieved by the fact that in a multichannel regulator containing a block of circulating devices, the first input is connected to the output of a set of Vehgichin sets, the second input through a block of measurements and conversions - to the output of a sensor block, the third input - to an output of a regulating device, and the remaining inputs to outputs relevant. corrective devices, the first output through the separation unit in time of the measurement and control processes - with the input of the regulating device, and the accumulators of analog values, connected by the first outputs to the inputs of the corresponding actuators, and the second outputs with the corresponding adjustment devices, additionally installed memory registers connected inputs with the corresponding outputs of the blocking device; outputs with the inputs of the corresponding drives of analog values. FIG. 1 shows the flowchart of the controller; in fig. 2 - the regulator is functional; in fig. 3 is a schematic of the setpoint; in fig. 4 is a block diagram of measurements and transformations (in Fig. 5 is a block diagram of circulating devices; Fig. 6 is a block diagram of a separation unit in time for measuring and regulating processes, Fig. 7 is a diagram of a regulating device; Fig. 8 is a diagram of a switching deviceJ Fig. 9 shows a storage register} in Fig. 10 is a diagram of a corrective device, and Fig. 11 shows a circuit of an analog value accumulator The device contains a set of 1 setpoint values, a block of 2 measurements and conversions, a block of 3 sensors, a block of 4 obegating devices , block 5 of separation in time pro measurement and adjustment sessors, regulating device 6, correction devices 7, accumulators 8 analog quantities, actuators 9, switchgear 10, memory registers 11, setting devices 12, measurement converters 13, sensors 14, pulse generator 15, counter 16, decoder 17, switches 18-23, delay block 24, adder 25, comparator block 26, elements 27 and 28, power amplifier 29, constant speed electric motor 30, reohord 31, resistors 32-49, operational amplifiers 50-53, diodes 54-57 , relay 58, pins 59, 60 and 61 of the relay, p Sistors 62-65, capacitor 66, transistors 67 and 68, microcircuit M002UI1 69, counter 70 pulses, decoder 71 ,, current switches 72, microcircuit M001AG1 73 and 74, capacitor 75, inverter 76, current switch 77, relay 78, operational amplifiers 79, 80 and 81, registers 82-88, diodes 89 and 90, transistors 91 and 92, I-NB elements 93, inverters 94, trigger 95, current key 96, relay 97; contacts 98 relays, feedback wound 99, potentiometer 100, capacitor 101, resistors 102, switch 103, resistor 104. The regulator operates as follows. The signals of the setpoint of the controlled parameter are formed in block 1 of the setting values individually for each channel of the multichannel regulator by setting devices 12. Setting device 12 is (fig. 3) a reohord 31, the slider of which is set by the operator, the voltage of the electric current removed from the slider the extreme point of the lead is a reference signal (setting). The power supply of the rack is carried out by a stabilized voltage source. Signals of information about the current value of the adjustable parameter are received from the sensor 14 of the block of 3 sensors. Typically, sensors 14 (for example, a thermocouple) have a nonlinear input-output characteristic and a low output level. To enhance the signals and linearize the characteristics of the sensors 14, their output signals are fed to the inputs of the corresponding measuring transducers 13 of the block 2 of measurements and transformations. FIG. 4, resistors 32-35 connected in a bridge circuit compensate for the effect of ambient temperature. The output of the sensor 14 is amplified by an operational amplifier 50, in which the resistors 36 and 37 set the required gain factor. Linearization of the characteristic of the sensor 14 is carried out by piecewise linear approximation using operational amplifiers 51 and 52 due to nonlinear feedback formed by diodes 54, 55 and 56, 57, respectively. A resistor 39 is applied to the inverting input of operational amplifier 51 via a resistor 39 U ,, through the resistor 43 to the inverting input of the operational amplifier 52, the reference voltage VQ is applied, thereby setting the turning points on the characteristic of the sensor 14. Resistors 38, 40, 41j 42, 44 and 45 set the operation mode respectively Ithel 5 Operatsionny 51 and amplifier 53 sums the outputs of the amplifiers 50, 51 and 52 with coefficients determined emymi resistors 46, 47, 48 and 49. With the measurements and transformations of signals normalized sensor unit 2 outputs 14 are input to the block 4 swept devices. At the same time, signals from block 1 of setting values and from outputs of correcting devices 7 come to input of block 4 of blocking devices. Block 4 of blocking devices includes a generator of 15 pulses, a counter 16, a decoder 17 keys 18, 19 and 20 and switchgear 10. The blocking device 4 commutates the signals of the sensors 14, the setting devices 12, the correcting devices 7 and the regulating signal from the block 6 in such a way that at a point in time, the input of the separation unit 5 in time is received only three signals: the signal of one sensor 14, one setpoint 12 and one correction device 7, and the output signal of the regulating device goes to only one actuating device 9. These signals are connected in series with dp of all channels by contacts 59, 60 and 61, relay 58 of the unit 4 bypass devices. The signals of the sensors 14 are connected through the contacts 59, the setting devices 12 through the contacts 60, the signals of the adjusting devices 7 through the contacts B1, and the signals of the regulating device 6 through the switchgears. To control the contacts 59, 60 and 61, pulses are generated when the capacitor 66 is flipped through the resistors 62 and 63 to the voltage set by the voltage divider on resistors 64 and 65. When the voltage on the capacitor 66 reaches the voltage on the divider, the composite thyristor breaks down on transistors 67 and 68, and the capacitor 66 is discharged and the output of the chip M002UI1 69 postzshaet pulse to the input of the counter 70 pulses. Resistor 104 sets the operating mode of transistor 68. The pulse duration is determined by the constant time of the QC circuit (resistors 62 and 63 and capacitor 66) and can be set depending on the requirements of the process. At the output of the pulse counter 70, a binary code is set corresponding to the number of pulses received at its input. The binary code from the output of pulse counter 70 is fed to the input of the decoder 71. The successive outputs of the depigapulator 71 through the keys 72 are connected to the +27 V voltage source of the 58 relay, each of which has three normally open contacts 59, 60 and 61. Signals switched by contacts 59, 60 and 61, are fed to the separation unit 5 in time of the process of coB measurement and control, which delays the transmission of these signals to the input of the regulator in order to eliminate the distorting effects of unsteady transients in measuring circuits for the formation of a regulating effect. The separation unit 5 in time for the measurement and adjustment processes consists of a delay unit 24 and a key. whose 21, 22 and 23. The delay unit contains the microcircuits M001AG1 73 and 74, which, together with the capacitor 75, perform the role of a single vibrator, an inverter 76, a current switch 77, through which the relay winding 7iB is turned on. When each pulse arrives from the output of chip M002UN1 69 of block 4 of the enclosing devices to the input of chip M001AG1 73 of block 5 of the time separation of measurement and control processes, a delay in the activation of the relay 78 relative to the moment of connecting the sensor 14, the setting device 8 and the correcting device 7 and thereby delaying the transmission of signals through contacts 79, 80 and 81 of the relay 78. Contacts 79, 80, 81 of the relay 78 act as keys 21, 22 and 23. Through the contact 79 to the input of the regulator 6 transmits a sensor signal. 14, through contact 80, the setting signal of the setting device 12, through contact 81, the signal of the correction device 7. The control device 6 consists of the adder 25 and the comparator unit 26. In the regulating device 6, the three input signals on the operational amplifier 79 are summed up, in which the required gain factor in the operating mode is established using resistors 82-86. Relay output characteristics, necessary for controlling constant speed actuators, are generated by a comparator, effective on operational amplifiers 80, 81, not covered by feedback, and diodes 89 and 90. The control signal deadband is determined by voltage + UucT The power of the control signal is amplified by transistors 91 and 92 with resistors 87 and 88 in the collector circuit. The output signal Vj of the operational amplifier 79 is compared with the voltage: the VIJC-T H -V unit (.f. The output signal of the regulator 6 is a two-digit binary code, which, depending on the ratio of the input signals. of the output signal of the operational amplifier 79, can take three values: 00, if -Vy. Vj + UChST, 0.1, if V4. g. + V, T, 10, if Vs :: -VijcT 06 .8 С regulating device 6, the output signal is fed to the first inputs of all switchgear 10, but passes only through the switchgear 10, the input of which receives a permit signal from the decoder 17. Switchgear 10 includes AND 27 and 28 elements. Each switchgear 10 consists of two logical elements NANA 93 and two inverters 94. The first inputs of elements 93 receive a signal from the regulating device 6, through the second combined inputs, the switchgear 10 is connected in series with the signals from the decoder 17. Thus, the output signal of the regulating device 6, which makes changes through the switchgear 10, it enters the input of the storage registers 11, where it is recorded and stored until the next time it is connected to this control channel. The storage register 11 of each channel consists of two triggers 95, each of which memorizes the corresponding state of the output signal of the regulating device 6. The output signal of the trigger 95 through the current switch 96 applies voltage to the winding of the relay 97. The output signal of the register 11 through the contacts 98 enters the drive input. 8 analog values and affects it (depending on the information recorded in the register) in three different ways, while the output signal of the accumulator 8 analog values either increases at a constant speed (in register -01) or decreases (in register-10), or remains unchanged (in register-00). Thus, a change in the regulating effect on the controlled process in the considered multipoint controller occurs not only while regulator 6 is connected to this channel, but after disconnecting the regulator from this channel by memorizing the output signal of regulator 6 memory register 11. When connecting pe91

the signal to be channeled to the next channel, the signal recorded in the storage register 11 of the previous channel corresponding to the value of the output signal of the regulating device 6 at the moment of leaving the previous channel continues to affect the corresponding 8. drive of analogue values.

The drive 8 analog values consists of a power amplifier 29, which uses a USh type magnet amplifier, and an electric motor 30, which is used as a single-turn, fixed-speed electric actuator of the MEO type. The voltage taken from the feedback reichord 99 determines the position of the regulator and goes to the corrective device 7 of the corresponding channel with which the proportional-integral regulation law is formed. From the output of the drive analog values 8 signal is fed to the actuating device 9.

The correction device 7 is an aperiodic link of the first order and consists of a switch 103, a potentiometer 100, a capacitor 101 and resistors 102. Using the potentiometer 100, the necessary factor pro6060610 is set.

proportionality. The switch 103 selects one of the resistors 102 and thereby establishes the necessary time constant for the integration.

The signals from the output of the corrective devices 7 are fed to the block 4 of the bypassing devices and through the contacts 61 to the input of the regulating device O 6. Thus, feedback from the output of the accumulator 8 of analogue magnitude to the input of the regulating device 6 is carried out.

fS Thus, in the storage register 11, the output signal of the regulating device 6 is memorized for the entire period while the regulating device 6 serves the other channels, i.e. The necessary change of the regulating effect of the regulator at the output of the actuating device 9 is carried out. The proposed device makes it possible to use multi-channel

25 a controller for controlling objects with a constant time of 3-5 seconds, while the basic controller A 306-14 without degrading the quality of regulation can be applied only to objects

30 s with a time constant of more than 100 s, i.e. the speed of the proposed controller increases by about 20-30 times, and the accuracy is about 1.5 times.

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Claims (1)

MULTI-CHANNEL REGULATOR containing a block of circulating devices, connected by the first input to the output of the set of reference values, the second input through the block of measurements and transformations - with the output of the sensor block, the third input - with the output of the control device, the remaining inputs - with the outputs of the corresponding correction devices, the first output through the separation unit during the measurement and regulation processes - with the input of the regulating device, and drives of analog quantities connected by the first outputs to the inputs of the corresponding and additionally devices and the second output with the corresponding correction devices, characterized in that, in order to increase the accuracy and control speed, it is further installed storage registers connected inputs to respective outputs of block swept devices, and outputs - to the inputs of respective storage of analog values. futl 1 1100606 2