BG62064B1 - Automatic system and method for the adjustment of the operation of a controllable valve - Google Patents

Abstract

The invention relates to an intelligent automatic system foradjusting the operation of a controllable valve and to method formonitoring and controlling the operation of at least aninterconnected valve and actuating mechanism. The system containsat least two input devices (20) the one serving to determine thetime position (21), and the second - for noise determination (23)depending on the position of the actuating mechanism (100). Theinput devices (20) are connected to the control devices of theactuation mechanism (50) across an analogue-digital converter (30)coupled to a microprocessor control device (10) which is connectedto devices for producing an output signal (40) and to acommunication receiver-transmitter device (70) for thecoordination of the system elements and for connection to anexternal communication network (80). The microprocessor controldevice (10) is coupled to power-independent memory (60). Themethod consists in initial determination of the characteristiccurves of open-closed position and reverse to the position asregards time and noise depending on the position of thecontrollable valve after which the actual position, the moment ofresistacnce and the noise are continuously measured and computedin the discretization cycle, the data being fed through thecommunication network. Continuous comparison is made with the datebase for the characteristics of the valve and in case ofdifferences a signal is supplied for their mending.

Description

The invention relates to an automatic control system and method for controlling the operation of a control valve, and in particular to an intelligent control system capable of recognizing the environment, and a method for controlling and controlling the operation of a connected valve and actuator, eg fluid-controlled.

2. BACKGROUND OF THE INVENTION

Valves are widely known in the art, whose position is controlled by various types of actuators. In order to automate and streamline the process of controlling the direction and speed of the actuator, various controls based on electronic means are used.

EP-0294918 electro-hydraulic servo system is known for controlling the positioning of control valves or other servo devices with automatic calibration capabilities. The system contains input means for determining the position of the actuator, by modulating voltage, microcontroller for switching on the actuator in the mode of automatic calibration for receiving data from the actuator, means for storing the calibration data, microprocessor for outputting the calibration data from the means for storing and determining the desired position of the actuator according to the calibration data, means for obtaining an output signal at any difference between the present and desired position of the actuator and means actuating the output signal and moving the actuator in the desired position.

The method by which the electro-hydraulic servo system described above is implemented is to calibrate by initially determining the OPEN CLOSED positions of the connected valve and actuator by turning the servo system to the fully open position, the measurement data is sent to microcontroller in digital form, and through a communication network this data is sent to a microprocessor, which in turn records them in nonvolatile memory. The servo system is then rotated to a fully closed position and in a similar manner the measurement data in digital form is sent to the microcontroller and via a communication network to the microprocessor, which records them by non-volatile memory. When a control signal is transmitted through a communication network converted into a digital form, the microprocessor determines the desired position using the calibration data. The actual position is measured and the data is digitally converted. The following is a comparison of the data defining the desired position with the data from the measurement of the actual position and outputting the signal in the presence of differences in the data to the actuator to move in the desired direction.

The disadvantages of the known solution are that the system switches to automatic mode only when submitting a new control signal, is not adapted to self-diagnosis and processes data from only one position sensor, which reduces the functionality and reliability of the system.

3. TECHNICAL SUMMARY OF THE INVENTION

It is an object of the invention to provide an automatic system and method for regulating the operation of a control valve so as to increase the functionality of the system and provide optimum operating conditions.

It is another object of the invention to provide an automatic control system for the operation of a control valve that is of higher reliability.

One third object of the invention is to simplify the system and to be capable of being constructed by conventional standardized means.

According to the invention, an automatic system for regulating the operation of at least one control valve connected to an actuator comprising input means for determining the position and resistance moment of the actuator, as well as second inlet means for simultaneously measuring the noise from the fluid flowing through the valve and the actuator noise. There may also be third input means for measuring the voltage applied to the actuator movement controls. The first two inputs are related to means for controlling the actuator movement through an analog-to-digital converter for converting the signals from the first two inputs to digital, which converter is connected to a microprocessor control device for environmental recognition and for controlling the operation of actuator control means by automatically actuating actuator control movement through a calibration sequence Calibration data retrieval positions for the associated valve timing actuator, by simultaneously processing and comparing data obtained from all inputs with a database of analogous data stored in non-volatile memories, at least one associated with the microprocessor control device and by determining the desired actuator position from the difference between the measured position data and the database. The microprocessor control device is also associated with means for producing an output signal, if there is a difference between the measured position data and the database related to the actuator movement controls of the actuator triggered by the output signal. The microprocessor control device is also connected to a communication transceiver for coordinating the operation of system elements and for connecting to an external communication network for receiving control signals and sending alarms in the event of both removable and irreversible defects in the operation of the microprocessor control device. connected valve actuator.

According to one variant embodiment of the system, the input means for determining the position and resistance moment of the actuator are contactless type.

In one embodiment of the system, the contactless means of determining the actuator position are a magneto-resistor type sensor.

In addition, the system contains means for compensating the temperature of the magneto-resistor sensor data according to the ambient temperature.

In one embodiment, the power terminals of the system are connected to the external communication network.

In another embodiment, the system includes means for locally signaling when signaling the actuator movement controls and if there are problems in its operation.

According to the invention, a method for regulating the operation of a control valve connected to an actuator is also provided, in which the calibration is initially performed by removing the characteristic OPEN state curves and vice versa with respect to the time and noise of the connected actuator valve, by giving the commands to the actuator the valve from the closed to the open position is sequentially recorded, the measurement data is stored in non-volatile memory, and then the valve is brought from the open to the closed position and the measurement data is stored in the nonvolatile memory. Then, the position and the resistance moment of the connected valve - actuator, the noise from the fluid flowing through the valve and the noise from the actuator are measured continuously and simultaneously at the sampling rate. The voltage applied to the actuator movement control means can also be measured by converting the data from all measurements from analog to digital through an analog-to-digital converter, after which the data from all measurements are compared with the calibration data and the database. for variables. Differences are identified and compared. When a control signal for the position of the valve is supplied by an external communication network, its data is stored in non-volatile memory in digital form, and the control signal is actuated by actuating the actuator control means. Then, the data from the measured actual position and resistance moment of the connected valve actuator is compared with the data of the control signal and, if there are differences, an alarm signal is sent to the peripheral communication network, triggering alarms and / or command for actuation of the means of controlling the movement of the differential actuation mechanism. According to the method, the working state of the electronic elements of the system is further continuously checked by examining the voltage applied to the actuators for controlling the actuator movement, and in case of failure of any of the electronic elements an alarm signal is sent on the peripheral communication network and triggered the means of signaling. According to the method, temperature compensation is also made for the dependence of the input means on the ambient temperature. By submitting periodic temperature measurement commands, the measurement data is digitally converted. they are compared with a temperature compensation database and a signal is sent to test the differences.

With the proposed automatic control system, the operation of a controlled valve continuously examines and monitors both the operation of the connected valve actuator and the status of the individual modules of the system, correcting and / or signaling errors of a temporary or permanent nature, which increases the functional capabilities of the system, saving time and labor and providing optimum working conditions.

By processing and comparing data from at least two independent inputs, the initial recognition of the type of valve and the type of associated actuator is made and their operating status is analyzed in a number of independent variables in a non-contact manner, which increases safety and hence and system reliability.

The system is built on a modular principle, which reduces the time for its recovery, under normal conditions makes it more serviceable and thus increases its reliability.

The availability of temperature compensation means increases the accuracy of the system.

By including the system power supply to the peripheral communication system, the installation of the system is simplified, the length of the cable used is reduced, which results in reduced time, labor and materials. Connection between the individual self-operated valves is provided, making the system decentralized.

DESCRIPTION OF THE FIGURES Attached

Figure 1 shows the characteristic curve of the OPEN-CLOSED state and vice versa for a ball valve:

Figure 2 shows the characteristic curve of the OPEN-CLOSED state and vice versa for a butterfly valve;

Figure 3 shows the noise characteristic curve of the OPEN-CLOSED state and vice versa;

Figure 4 shows the curves of a temperature compensated and temperature uncompensated magneto-resistor sensor;

Figure 5 shows a block diagram of the hardware of an actuator driven automatic valve control system;

Figure 6 shows a block diagram of a microprocessor for the automatic system of Figure 5;

Figures 7a and 76 show an exemplary electrical diagram of the system of Fig. 4 with a magnetic position resistor type sensor and a pneumatic actuator actuated by electrical distributors;

Figures 8a and 86 show the system operation algorithm of Fig. 4.

5. EXAMPLE IMPLEMENTATION OF THE INVENTION

Figures 1, 2, 3, and 4 show different characteristic curves that may be part of the system database.

Figure 5 shows a block diagram of hardware of an exemplary embodiment of an automatic system according to the invention, wherein the microprocessor control device for recognizing the environment and for regulating the operation of the coupled valve actuator is configured as a microcontroller 10, and Fig. 8 shows the algorithm of operation of system. Figure 5 shows the input devices 20, respectively the position sensor 21, the means for measuring the voltage 22, the noise sensor 23 and the temperature sensor 24, connected via an analog-to-digital converter 30, the microcontroller 10 and means for producing an output signal 40 with means 50 for controlling the actuator movement, respectively, of the electric valves 51 and 52. The microcontroller 10 is connected to a non-volatile memory 60 EPROM for storing data and for storing data in which the program is stored, and through a communication device. emo transceiver 70 for connection and coordinating operation of the components of the system to an external network 80, such as type

LONWORKS, for receiving control signals and sending information and alarm signals for both reflective and irreversible defects in the operation of the connected valve actuator. The means 40 are connected to means 90 for indicating defects in the state of the system and for indicating an output signal, which in this case are made as two LEDs 91 and 92. The means 40 include the input means 22 for measuring the voltage of the output signal. The means 50 are connected to a control valve 100 consisting of a connected valve 101 and an actuator 102.

According to FIG. 6, the microcontroller 10 may include three microprocessors 11, 12 and 13, with the microprocessor 11 serving to communicate with the external communication network 80, the microprocessor 13 serving to monitor, adjust, and form commands, and the microprocessor 12 to communicate between the two. The microcontroller 10 has an adaptation means 14 associated with the external communication network 80, an input-output device 15 associated with a counter and a timer for forming discrete signals, means 16 to synchronize the operation of the microcontroller, and means 17 to communicate with the external memory 60. There are also two memories 18 and 19 in the microcontroller 10, respectively RAM and EEPROM.

In the exemplary wiring diagram shown in FIG. 7, the position sensor 21 is designed as a magneto-resistor bridge, the voltage measuring means 22 are integrated into the means 40 to produce an output signal, in this case a pulse power converter designed as a chip that can be a NATIONAL SEMICONDUCTORS chip with catalog number LMD 18400 and the noise sensor is a microphone. The analog-to-digital converter 30 is designed as a chip, which may be, for example, an ANALOG DEVICES chip with part number AD 7714. The non-volatile memory 60 connected to the microcontroller 10 is also a standard chip, and in this case the transceiver 70 is provided with a chip of ECHELON with catalog number LPT-10 for connection to the external communications network, in this case LONWOKS. The means of temperature compensation, in this case temperature sensor 24, may be a standard LM 35 type NATIONAL SEMICONDUCTORS sensor.

The method of the invention is illustrated by the operation of the system of Fig. 4, controlled by a program whose algorithm is shown in Fig. 8. The use of this algorithm requires the presence of more than one input jigsaw, which are processed in such a way as to ensure automatic monitoring in a dialog mode of changes in the environment and in the operation of the system itself. An initial calibration mode and corresponding recognition of the valve type and actuator type are also provided.

According to the algorithm of FIG. 8, after switching on the system to the power supply, a command is sent from the microcontroller 10 through the means 40 to produce an output signal to the valves 51 and 52 for opening the valve 101. The open position of the actuator 102 and the noise received during operation of the controlled valve are measured. 100 to the fully open position, the signals being digitally converted and stored in the non-volatile memory 60. Then, a command from the microcontroller 10 is passed through the means 40 to the valves 51 and 52 to close the valve 101, by analogy measuring the position and noise of the closed state and the signal in digital form is recorded in the memory 60. A command is given for only calibration of the gain of the position controller and the curves are OPEN closed and vice versa with respect to time. The measurement data is stored in the memory 60. From the characteristic curves taken and compared with a database of similar curves from the memory 60, the system automatically recognizes the type of valve structure 101 and the type of actuator 102. For example, when comparing the characteristic curves of FIG. 1 and 2 show that the curves differ for different types of valves. The disymmetry in the characteristic curves when opening and closing the valve 101 determines the type of actuator 102, for example, whether it has a spring or no spring, from which it is judged by the number of means 50 to actuate it. From the change in torque to the end positions of the valve 101, reflected in the characteristic curves, the position of the actuator 102 OPEN - CLOSED is judged. The speed of displacement, reflected in the characteristic curves, judges the correctness of the selection of the actuator 102 and the violation of its performance. The opening and closing noise characteristics determine the cavitation zone, which is fixed in the position characteristic, and is judged on the state of the valve 101 and in particular whether it is sufficiently sealed in the closed position.

After performing the calibration once, the temperature is continuously measured over a period of time, the measurement data is digitized, compared with a temperature compensation database and a signal is sent to test the differences. At the same time, the actual position and the resistance moment of the control valve 100 are measured, the data is digitally converted to the analog-to-digital converter 30 and compared to the calibration position data. At the same time, the noise from the fluid flowing through the valve 101 and the noise from the actuator are simultaneously measured and compared in a similar way to the calibration noise data. In the case of problems, the voltage supplied to the valves 51 and 52 is also measured and compared to the limit values of the variable database. The differences in the microcontroller 10 are determined and compared with each other. A command is given to the differential valves 51 and 52 and the LEDs 91 and 92 are activated. If the difference cannot be overcome, the LEDs 91 and 92 continue to be switched on and an alarm signal is sent through the external communication network. In this way, a cavitation warning, mechanical blockage of the valve 101 or actuator 102, pressure drop in the pneumatic system of actuator 102 and other mechanical problems are obtained.

When the control signal for changing the position of the valve 101 is transmitted through the peripheral communication network 80, its data is recorded in digital form in the EEPROM memory 19, the valves 51 and 52 are actuated and the command is executed. Then, the data from the actual measured position of the control valve 100 is compared with the data from the control signal and, if there are differences, a command is given to activate the valves 51 and 52 to test the differences and the LEDs 91 and 92 are activated. If the difference cannot be is overcome, indication means 90 remain on and an alarm signal is sent over the external communication network 80.

The voltage applied to the valves 51 and 52 is measured by integrated circuits in the output signal means 40, and after a comparison with the base data, an alarm 90 is triggered when exceeding the permitted limits and an alarm signal is sent over the network 80. differences in acceptable limits, the system adapts to EEXI operation. From measurement, the system automatically determines whether to remain on or whether to remain off to prevent permanent damage.

The present invention is presented in an exemplary embodiment, which is not intended to limit the inventive idea, but merely for illustration purposes, the scope of the invention being determined only by the appended claims.

Claims (6)

Patent Claims 1. An automatic control system for the operation of a control valve connected to an actuator comprising input means for determining the position of the actuator associated with means of controlling the actuator via an analog-to-digital converter connected to a microprocessor-controlled actuator for actuating the actuator in automatic position calibration mode, with the microprocessor controller associated with at least one non-volatile memory and associated with a medium and for producing an output signal for processing the differences that the means are associated with the actuator control means, characterized in that there are at least one more input means (22) for measuring the voltage applied to the control means (50) of the actuator and / or input means (23) for measuring noise associated with the actuator means (50) for controlling the actuator through the analog-to-digital converter (30) connected to the microprocessor control device (10) recognizing the environment by simultaneously processing and comparing input data (21, 23) to determine the actuating torque of the actuator and controlling the action of the actuating means (50) by determining the desired actuator position as differences between the measured and the database, wherein the microprocessor control device (10) is also connected to a communication transceiver (70) for connection and coordination of the operation of an element They system with an external communication network (80). An automatic control system for the operation of a control valve according to claim 1, characterized in that the inlet means (21) for determining the position and resistance moment of the actuator are non-contact type. An automatic control system for the operation of a control valve according to claim 2, characterized in that the contactless means are a magnetoresistor type sensor. An automatic control system for the operation of a control valve according to claims 1, 2 and 3, characterized in that the system's power terminals are connected to the external communication network (80). 5. A method for regulating the operation of a control valve connected to an actuator, in which an automatic calibration is performed at OPEN-CLOSED state by actuator position, digital data is recorded in non-volatile memory, a control signal is transmitted through the communication network and converted to digit ^ bNd by recording in non-volatile memory, actual actuator position is measured and the data is digitally converted, the measurement data and the control signal are compared in the microprocessor control unit and an output signal is output to the actuator in the presence of differences m for differences, characterized in that the automatic calibration takes the characteristic curves of the OPEN CLOSED state and vice versa by measuring the position with respect to time, by calculating the resistance moment of the controlled valve and by measuring the noise with respect to the position of the coupled valve actuator and the digital data are recorded in non-volatile memory (60), and the position, resistance and noise of the fluid and the operation of the coupled valve the filling mechanism is continuously measured at a sampling rate, the data being digitally compared with the calibration data and the variable database and transmitted over the communication network (80), and in the case of differences between the actual position data, the resistance moment and noise of the connected valve actuator and control signal data, an alarm signal is sent to the peripheral communication network (80) and / or a command is made to detect differences, whereby they are continuously performed. perature compensating the dependence of the input means on the ambient temperature A method for regulating the operation of a control valve according to claim 5, characterized in that the voltage applied to the actuator control means is continuously measured at a sampling rate, which is compared with basic data stored in energy independent memory (60 ) and when modified, an alarm is sent and / or the system automatically shuts off.