SU1725182A1 - Programmable controller - Google Patents

Abstract

This invention relates to automation and computing. It can be used in the energy, gas / IU petroleum and other industries. The purpose of the invention is to increase the reliability of the process control system. The programmable controller contains the control computing unit 1, two interface blocks of input 2 and output 5, input 3 and output 4 storage blocks, scanning unit 6. It additionally includes the address selector 7, register 8, control unit 9 and reset element 10. The introduced blocks provide control of the parameters of the controlled object independently of the computing device. If the parameter takes the alarm value, the alarm code is recorded in the register and the object is turned on from the master inputs through the interface output block. This ensures the protection of the controlled object in an emergency situation regardless of the malfunction of the control computing unit. 2 Il. AND

Description

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The invention relates to automation and computing and can be used in the energy, gas, oil and other industries in the automation of technological processes.

The aim of the invention is to increase the reliability of the process control system.

Figure 1 shows the block diagram of the programmable controller; figure 2 is an example of its implementation.

The controller contains the control computing unit 1, the interface input unit 2, the input storage unit 3, the output storage unit 4, the interface output unit 5, the scanning unit 6. the address selector 7, the register 8, the control unit 9 and the reset element 10, the inputs parameters, control outputs, address outputs, parameter code outputs, control code outputs, alarm reset input, alarm signal output, and setting inputs.

Control computational unit 1 receives digital codes from the input storage unit 3 having the meaning of the input parameters, processes them in accordance with the stored program, and outputs the processing results in the form of digital codes to the output memory. The output digital codes have the meaning of the values of the output control signals of the object and the control codes, which include or deactivate the control of certain values of the parameters.

The control computing unit can be executed in any known manner, for example, in the form of a digital computer containing a processor interconnected by interface connections, a permanent storage device with a program stored therein, a random access memory for intermediate storage of results, and contain an I / O device, including a communication device with an object. In the example shown in FIG. 2, the computing device is implemented on the Lomikont logic microprocessor controller, the interface terminals of the reading of unit 1 are connected to the corresponding terminals of the input storage unit 3, and the interface terminals of the recording are with the terminals of the output storage unit 4 of the same name ..

Interface pins include the outputs of address A, to which the address code of the subscriber is being sent.

the exchange, bidirectional data outputs D, to which readable data is written or received, readout outputs RD and WR records, which exhibit read and write operations, respectively, input response AN, to which a signal to establish connection with the subscriber is received.

Pins A, D, RD, and AN relate to the read pins, A, D, WR, and AN pins to the write pins. The reading of the input storage unit 3 (subscriber) is carried out as follows: the control computing unit 1 exposes at the outputs A an address code, and at the output RD a reading sign. The subscriber transmits a data code to the inputs D and sets a validity code of the data code at the input AN. The computing device receives the data and removes the address code and the read flag.

Writing to the output memory 4 (subscriber) is carried out as follows; the computing device exposes at the outputs A, D, and WR an address code, data code, and a sign of the record, respectively. The subscriber receives the data and exposes a data acquisition signal at the input AN. The computing device removes the codes from the outputs A, D and the signal from the output AN.

The input interface unit 2 converts electrical signals into digital codes, such as discrete-digital, and in turn outputs digital codes to the data outputs in accordance with the codes on the address inputs. The electrical signals are the parameter values of the controlled object and are fed through the parameter inputs of the controller to the inputs of the parameters X / D of block 2. The address inputs of the SED of block 2 are connected to the address outputs of the scanning block 6. Codes of electrical signals (parameters) from the data outputs D unit 2 is alternately received at the data inputs of the input storage unit 3 and the inputs of the parameter codes D. 1 register 8 under the control of the scanning unit 6. The input modules of the communication device can be used as an input device with the object of serial control digital computers.

The input storage unit 3 is designed to store the codes of input parameters (electrical signals) and contains a decoder 11, a drive 12 and a delay element 13. The basis of the input storage unit 3 is the drive 12, made in the form of a file recorder with

by separate decoding and addressing, both for recording and for reading information, which allows simultaneous recording to one address, and reading to another, performed, for example, on the basis of a K555IR chip 26,

Drive 12 is the storage location for the codes of the input signals (parameters) of the controller. The data inputs D of the accumulator 12 through the data inputs of the input storage unit 3 are connected to the data outputs of the input device 2, the inputs for selecting the write address through the inputs of the recording address of the input storage unit 3 to the address outputs of the scanning unit 6, the enable input of the SEW record through the input synchronization input recording memory unit 3 is connected to the sync output of the scanning unit 6. To record the input data, they are fed to inputs D, to the inputs for selecting the address of the SEWR record, the address code is applied even after the transient processes have completed x accumulator 12 is supplied to the input signal EWR resolution recording.

Thus, the codes of input electrical signals (parameters) of the controller under control of the output signals of the scanning unit 6 are alternately transferred to the accumulator 12. The data outputs of the storage device 12 are connected to the data terminals D of the computing device 1 via the data outputs of the input memory unit 3, the SER of the read address selection through the inputs of the selection of the reading address of the input storage unit 3 to the outputs of the address A of unit 1, the input of the read resolution ERD to the output of the decoder 11.

The decoder 11 recognizes by the code on the inputs D of the access to the drive 12 by reading. The data inputs D of the decoder 11 are connected to the inputs for selecting the reading address of the input storage unit 3, the synchronization input C via the read synchronization input of the input storage unit 3 is connected to the read output of the RD unit 1. The output of the decoder 11 is connected to the input of the delay element 13, the output of the latter is connected through the output the response of the input storage unit 3 with the input of the response of the AN unit 1.

The combination of data outputs, read address selection inputs, a read synchronization input, and a response output output of the input storage unit 3 forms its interface read outputs. To read the output data, the address code is supplied to the read address of the input storage unit 3 and the read address select input of drive 12. At the same time, the same code is fed to the inputs D of the decoder 11, to

synchronization input C (of the latter) through the input synchronization of the reading of the input storage unit 3, a reading signal is supplied. The decoder 11 recognizes the code supplied to its inputs D, generates an output signal supplied to the input of the delay element 13 and the read enable input of drive 12.

The data outputs of accumulator 12 include a data code corresponding to its address at the inputs of the SER. After the time required for the end of the transient processes in the accumulator 12, the delay element 13 generates a signal at the response output

5 data reliability at the data output supplied to the input AN of block 1. Thus, the input storage unit 3 outputs for reading in block 1 under the control of the latter the code of the input electrical signals (parameters) of the controller.

The output memory unit 4 is designed to store the codes of the output (control) signals of the controller and the control codes and contains a decoder 14, a de5 encoder 15 with a delay, a drive 16 and an isolation element 17. The basis of the output storage unit 4 is constituted by the accumulator 16, also executed as a register file with separate decoding and addressing of words both for recording and for reading information, which allows simultaneous recording at one address and reading at another. The drive is the storage location for output codes and control codes.

The data inputs of the drive 16 are connected through the data inputs of the output storage unit 4 to the data terminals of the D unit

0 1, the inputs for selecting the write address SEN through the inputs of the write address of the output storage unit 4 to the outputs of the address A of block 1, the write enable input EWR to the output of the decoder 15 with a delay.

5 The delay decoder 15 recognizes, by the code on the inputs D, the write access to the storage drive and delays the output signal in the output circuits. Data inputs D decoder 15 with a delay

0 is connected to the write address of the output of the output storage unit 4, the synchronization input C through the write synchronization input of the output storage unit 4 is connected to the write output WR of the unit 1.

5 The output of the decoder 15c is connected with a delay to the input of isolation element 17, the output of the last connection via the output of the response of the output storage unit 4 to the input of the response AN of the computing device 1. The set of data inputs, inputs for selecting the write address, synchronization input for the recording and output of the output of the output storage unit 4 forms its interface write outputs.

To write the input data to the inputs of the write address of the output storage unit 4 and the inputs for selecting the write address of the SEW drive 16, an address code is supplied. At the same time, the same code is applied to the inputs D of the decoder 15 with a delay. A write signal is sent to the synchronization input of the latter via the write synchronization input of the output memory unit 4. The delay decoder 15 recognizes the code supplied to its inputs O, and after the time required to complete the transient processes in the drive 16, generates an output signal supplied to the input of the isolation element 17 and the write enable input of the drive 16.

In drive 16, the information from the inputs D is recorded at the address given by the code at the inputs of the SEW, the output of the junction 17 is the signal applied to the input AN of unit 1, indicating that the information has been received. Thus, the output memory unit 4 receives the codes of the output signals of the controller and the control codes. The data outputs D of the accumulator 16 are connected via data outputs of the output storage unit 4 to the data inputs of the output interface unit 5 and the DO control code inputs 8. The read address selection inputs SER are connected via the address inputs Read output memory unit 4 to the address outputs of the scanning unit 6, input the read resolution ERD is connected to the output of the decoder 14, the data inputs of which D are connected to the address inputs Reading the output storage unit 4.

Address codes arrive at the read address selection inputs SER of accumulator 16 and inputs D of the decoder 14. The decoder recognizes the inversion and sends a signal to the read enable input of accumulator 16. The accumulator 16 sets information at the data outputs stored at the address defined by the code on the SER inputs . This information is fed to the data inputs of the interface output unit 5 or to the inputs of the DO control codes of the register 8. Thus, output (control) signals or register 8 control codes controlled by the scanning unit 6 are transferred from storage device 16 to output unit 5.

Unit 5 is designed to convert alternately incoming data codes to its inputs into parallel control signals supplied to the controlled object and to switch control from the master

controller inputs in an emergency. Block 5 contains a decoder 18, a group of gist and a group of switches (in FIG. 2, one register 19 and a switch 20).

The decoder 18 is designed to identify the address of each register in the group, for example, register 19 in order to select a register in which the code from the data input corresponding to the current address is written.

Each of the registers of the register group is intended to store the code of the output signals. Each switch group provides digital conversion

5 codes, stored in the corresponding register, into electrical signals (signal) of control of the object. In an emergency situation, each switch of the group provides such a conversion for a digital code supplied to the corresponding setting inputs of block 5. Data inputs D of the decoder 18 are connected via address inputs Record of block 5 to the address outputs of scanning block 6, input

5 synchronization C - via the synchronization input of the unit 5 with the sync output of the scanning unit 6.

Each data output of the decoder 18 is connected to the synchronization input (C) of the corresponding register (19). The data inputs (D) of each register (19) are connected via the data inputs of block 5 to the data outputs of the output memory block4. The data outputs (D) of each register (19) are connected

5 with the first data inputs (DO) of the corresponding switch (20). The second data inputs (D1) of each switch (20) are connected via the corresponding master inputs of block 5 with the corresponding master inputs of the controller. The switching input to the second inputs (CS1) of each switch (20) is connected via the switching input of block 5 to the direct output of trigger 10, each output (D / V) of the switch

5 (20) is connected via the corresponding control output of the unit 5 with the corresponding control output of the controller.

The codes of the output signals to the register 19 from the output memory device are recorded under the control of the scanning unit 6 as follows. The current address code is fed to the data inputs D of the decoder 18, the code of the corresponding control is applied to the inputs of block 5

5 signals (signals). Thereafter, a clock signal is applied to the synchronization input C of the decoder 18. The decoder 18 recognizes the access to the register, for example, the register 19, and produces a signal at the corresponding output. This signal is sent to the input.

synchronization of the register C and causes the register to write a code from data input D. The code from the data output D of the register is fed to the first DO inputs of the corresponding switch, for example switch 20, where it is converted into electrical output signals (signal if digital-analog conversion is meant).

Thereafter, the next code is sent to the address inputs and inputs of block 5, which is received and converted similarly to other register and switch, respectively. In the event of a fault, the input of the selection of the second group of inputs of the switch 20 receives a signal and the switch 20 sets the input signals of its output converters to code from the driver inputs.

Scanning unit 6 is intended to iterate through addresses related to unit 2, input 3 and output 4 storage units, unit 5, register 8, and synchronize the write procedure when issuing each address. The scanning unit contains a generator 21, a delay element 22 and a binary counter 23. The generator 21 generates periodic pulses. The output of the generator is connected to the input of the delay element 22 and the content increase input on G of the binary counter 23. The delay element 22 delays the formation of a sync signal, whose leading edge is delayed relative to the leading edge of the generator signal 21. The output of the delay element 22 is connected to the sync signal output of the scanning unit 6. Binary the counter keeps a continuous count of the pulses of the generator 21, when overflow the count is resumed from the initial state. The outputs of the counter bits are connected to the corresponding bits of the address outputs of the scanning unit.

The address selector 7 is designed to select among the entire continuous sequence of addresses issued by the scanning unit 6, the addresses of the codes of the controller's input signals, which can take alarm values. The data inputs D and the sync input C of the address selector are connected respectively to the address outputs and the sync output of the scanning device, the output to the enable input of the E register 8,

Register 8 is designed to store the alarm code, which carries information about the alarm signal: signal address code, (signals), signal value code (signal values), control code. In the non-emergency state of the controlled object, when there is a reception enable signal at input E and there is no prohibition signal at the input DE, the register transmits the input information to the corresponding outputs. In the event of a fault at input E, a prohibitory signal appears and information stored at the time of the signal at input DE is stored in the register. Address inputs D2 of the register are connected to the address outputs of the scanning unit 6, the input enable input E is connected to the output of the address selector 7, the deny input DE is from

0 direct trigger output 10. The outputs of the DO control codes, the D1 parameter codes and the D2 address register of the register 8 are connected respectively to the controller outputs of the same name. In addition, the outputs of the DO control codes and

5 parameter codes D1 are connected respectively with the same inputs of the control unit 9.

The control unit 9 performs a random analysis of the codes of the input signals and, in the case of their alarm values, generates a signal for latching the alarm state. 2, the control circuit is executed on the two-input AND elements, the outputs of which are combined according to the OR scheme. For each scheme AND

5, the parameter code bit and the corresponding control code bit are submitted. The control block contains as many of the specified schemes And, how many bits at the parameter code or control code, the Control of the corresponding

The 0th bit of the parameter code is turned on by the level Log.1 in the corresponding bit of the control code, and the alarm state corresponds to the level Log.1 in the bit whose control is turned on, which is ensured

5 conversion to input 2 input device. For analog-to-digital conversion, the alarm value corresponds to the level of Log.1 in all bits of the digital code (scale value

0 parameter). The control unit will work, if on both inputs of at least one element I the level 1 is set. The output of the control unit 9 is connected to the information input of the reset element.

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The reset element 10 is made on a trigger and is intended to provide the possibility of resetting the detected emergency state. Installation input

0 Log. 0 R is the inhibit input of the reset item and is connected to the reset input of the controller alarm. If signals are simultaneously applied to the S and R inputs of the trigger, the latter is set to state 5 Log.O, i.e. the log level is set at the direct output. A. To issue an external message, a direct trigger output, which is the output of a reset circuit, is connected to the output of the controller alarm signal. All connections are in the address chain and

controller data (by which codes are transmitted) are executed bitwise, i.e. the low-end output is connected to the low-level input, and so on. Interface communications between blocks 1.3 and 4 (Fig. 2) are represented by address buses 24, data 25, reads 26, entries 27, answers 28. The output buses of the scanning unit 6 are represented by address buses 29 and sync signal 30.

The controller in a non-emergency situation works as follows.

The values of the object parameters are transmitted as electrical signals to the inputs of block 2, and converted into digital codes in its input circuits. For an analog-to-digital converter, a digital code carries information about a single signal, for a discrete-digital one, several numbers of bits in a digital code. Under the influence of the scanning unit 6, these codes are constantly rewritten into the input storage unit 3, and the address of each code of the unit 2 coincides with the address of this code in the input storage unit 3, since reading the code from unit 2 and writing it to the input storage unit 3 the same address determined by the scanning unit 6.

Unit 1 reads information about the state of the controlled object, processes it in accordance with the program stored in it, and generates digital codes of the object control signals into control codes, which it writes to the output memory unit 4. Under the influence of the scanning device 6, the object control signal codes are rewritten from the output storage unit 4 to the unit 5, where they are converted into object control signals. The transfer of the codes of the input signals of their block 2 to the output memory unit 3 and the codes of the output signals of block 5 are repeated in each cycle of the scanning block 6.

To achieve the required control speed, the cycle duration is selected by a sufficiently small relativity of transients in the controlled object. Simultaneously with the specified object control process, the output parameter values are monitored as follows.

Along with the control output codes of the controller, unit 1 writes into the output storage unit 4 current control codes that enable or disable control of the code bits of the input signals (parameters) in accordance with the object control program. The address of each code input signals in the input

the storage unit 3 coincides with the address of the control code corresponding to this code in the output storage unit 4. The address selector 7 displays all these addresses

and includes the resolution of writing to register 8. Thus, the codes of input signals from block 2, the corresponding control codes from the output memory block 4 and the address

0 of these codes from the scanning unit 6.

From the outputs of register 8, the code of the input signals (input signal) and the corresponding control code go to block 9 of the control. If the code of the input signal does not correspond to the value determined by the control code, the control unit 9 will generate a signal for setting the reset element 10 to the Log.1 state. The reset element 10 generates a signal to block the reception of information in

0 register 8, in which the code of the input signal (signals) with the alarm value, the control code and their address are stored. This information is provided to the corresponding controller outputs and is sufficiently 5 to unambiguously determine the root cause of the accident.

At the same time, an alarm signal is output to the external circuits from the reset element 10, and the controller outputs

0 are switched to control from the driver inputs of block 5, which determine the controller output signals in an alarm condition. The driver inputs can be connected to remote control switches, then the operator takes control of the object to another controller, which sets the object's further control procedure. Fixed signals can also be sent to the driver inputs to ensure the safe behavior of the object.

In each current operating state of the controller, all information about the parameters of the object is stored in the input memory 5, go to block 3, and about the output control signals and control codes in the output memory unit 4. If the control computing unit fails, the control continues with the installed output control signals until an object parameter accepts an alarm value. If any parameter accepts the alarm value, the control circuit will trigger, on

5, the direct output of the reset element 10 is set to the level Log., 1, the switch 20 generates signals in accordance with the code on the controller inputs, the controller issues control signals preventing catastrophic consequences on the controlled object, and information on the alarm parameter. An example of such equipment may be a boiler. After removing the boiler to a nominal load, it is necessary to monitor a number of its parameters, which can take emergency values, for example, the presence of a torch, the flow of water through the boiler, etc.

If one of these parameters takes an emergency value, it is necessary to prevent catastrophic consequences, such as an explosion of a mixture of fuel and air residues in the boiler furnace in the absence of a flame in the furnace, overheating and destruction of the boiler in the absence of water flow, etc. The usual actions in these cases are: the fuel supply valve is closed and the fans are turned on to ensure that the furnace is ventilated from the remnants of an explosive mixture of fuel and air. All these tasks are solved by the proposed controller in the event of a computing device failure. If a no-flame signal is received, the control circuit 9 triggers and switching to the driver inputs the output device 5 switches on the fuel shut-off signal and the fan turn-on signals to ventilate the furnace.

The advantage of the proposed controller is that in the event of a computing device failure, its repair or replacement is feasible without stopping the controlled boiler, as the control signals are issued, and in the event of an emergency parameter value, the necessary safety measures are taken. Due to the fact that the shutdown and ignition of the boiler unit are associated with energy costs, and the controller prevents the shutdown and subsequent ignition of the boiler unit, the proposed device provides energy savings.

Fo rumula and z oo n i ya Programmable controller that contains a control computing unit, an input interface unit, an input storage unit, an output storage unit, an interface output unit, a scanning unit, interface outputs of the Read, Write control modes the computational computing unit are connected to the corresponding like-named outputs of the input storage unit and the outputs of the output storage unit, the address outputs of the scanning unit are connected

correspondingly with the address inputs of the input interface block, address inputs Record input storage block, address inputs Read output memory block, address inputs Record interface output block, clock output of the scanning block connected to synchronization inputs Record input memory block and interface

the output unit, the input parameters of the input interface unit are connected respectively to the parameter inputs of the controller, the data outputs of the input interface unit are connected respectively to the data inputs of the input storage unit, the data outputs of the output memory unit are connected respectively to the data inputs of the output interface unit, the control outputs of which are connected respectively , with the control outputs of the controller, and the driver inputs are respectively connected to the driver inputs of the controller, characterized in that In order to increase the reliability of the process equipment control system, an address selector, a register, a control unit and a reset element are entered into it, the address outputs of the scanning unit are connected respectively to the address inputs of the address selector and register, the sync output of the scanning unit is connected to the address input selector of the same name, output which is connected to the register enable input, the code inputs

the register parameters are connected respectively to the data outputs of the input block, the register control codes inputs are connected respectively to the data outputs of the output memory block, the register address outputs are connected to the controller outputs respectively, the register parameter codes outputs are connected to the parameter codes outputs, respectively

control block, register control code outputs are connected respectively to controller control code outputs and to control block code inputs, the output of which is connected to the information input of the element

reset, the prohibition input of the reset element is connected to the reset input of the alarm controller, the output of the reset element is connected to the output of the alarm signal of the controller, the input blocking register and the input

switching interface output unit.

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Claims (1)

Claim A programmable controller comprising a control computing unit, an input interface unit, an input storage unit, an output storage unit, an output interface unit, a scanning unit, interface outputs of the Reading, Writing control computing unit are connected to corresponding outputs of the input storage unit and outputs of the output storage unit, the address outputs of the scanning unit are connected respectively to the address inputs of the input interface unit, the address inputs the memory block, the address inputs Read ”of the output memory block 5, the address inputs Write the interface output block, the output of the scan unit clock is connected to the synchronization inputs Write the input memory block and the interface 10 output block, the inputs of the parameters of the interface input block are connected respectively to the inputs of the controller parameters, the outputs the data of the input interface unit are connected respectively to the inputs of the data of the input storage block15, the data outputs of the output storage unit are connected respectively, with the data inputs of the interface output unit, the control outputs of which are connected respectively, with the control outputs of the controller, and the control inputs are respectively connected with the control inputs of the controller, characterized in that, in order to increase the reliability of the control system of the technological equipment, a selector is inserted into it addresses, register, control unit and reset element, the address outputs of the scanning unit are connected respectively to the address inputs of the address and register selector 30, the clock output The scanning unit is connected to the input of the address selector with the same name, the output of which is connected to the register enable input, the inputs of the codes 35 of the register parameters are connected respectively to the data outputs of the input unit, the inputs of the register control codes are connected respectively to the data outputs of the output storage unit, address outputs of the register are connected respectively, with the address outputs of the controller, the outputs of the codes of the parameters of the register are connected respectively with the outputs of the codes of the parameters of the controller and with the inputs of the codes of the parameters ov 45 of the control unit, the outputs of the control codes of the register are connected respectively with the outputs of the control codes of the controller and with the inputs of the codes of the control unit, the output of which is connected to the information input of the reset element 50, the inhibit input of the reset element is connected to the reset input of the controller alarm signal, the output of the reset element is connected to the controller alarm output, the register reception lock input and the input switch 55 of the output interface unit. 5U