EP1346491A1 - Commande d'une installation de traitement comprenant un ou plusieurs objets - Google Patents

Commande d'une installation de traitement comprenant un ou plusieurs objets

Info

Publication number
EP1346491A1
EP1346491A1 EP01999864A EP01999864A EP1346491A1 EP 1346491 A1 EP1346491 A1 EP 1346491A1 EP 01999864 A EP01999864 A EP 01999864A EP 01999864 A EP01999864 A EP 01999864A EP 1346491 A1 EP1346491 A1 EP 1346491A1
Authority
EP
European Patent Office
Prior art keywords
parameter
data
control
objects
alarm
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
EP01999864A
Other languages
German (de)
English (en)
Inventor
Niels Skov Veng
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of EP1346491A1 publication Critical patent/EP1346491A1/fr
Ceased legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B19/00—Programme-control systems
    • G05B19/02—Programme-control systems electric
    • G05B19/418—Total factory control, i.e. centrally controlling a plurality of machines, e.g. direct or distributed numerical control [DNC], flexible manufacturing systems [FMS], integrated manufacturing systems [IMS], computer integrated manufacturing [CIM]
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B2219/00—Program-control systems
    • G05B2219/30—Nc systems
    • G05B2219/32—Operator till task planning
    • G05B2219/32154—Object, attribute for geometry, technology, function oop
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P80/00—Climate change mitigation technologies for sector-wide applications
    • Y02P80/10—Efficient use of energy, e.g. using compressed air or pressurized fluid as energy carrier
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P90/00—Enabling technologies with a potential contribution to greenhouse gas [GHG] emissions mitigation
    • Y02P90/02—Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Definitions

  • the present invention concerns a method for controlling a process plant including one or more objects.
  • control was individual and with feedback from the human senses which interfered if any undesirable situations arose.
  • control units With the computer, one got flexibility and easy access to extensions.
  • the computer In the case of control units, the computer is viewed in two ways: As a control adapted to a certain industry but with flexibility within the industry, or as a universal control expressed in the PLC.
  • the invention differs from the prior art by comprising a method which is peculiar in including one or more objects, where for each object there is a pre-defined parameter depending on the function of the object, in which:
  • the object controls the process parameter so that it falls within the predefined parameter
  • - the predefined parameter is communicated to the object as a value which by data processing on the object is translated to a control parameter
  • control parameter is communicated between a control unit and one or more objects by data communication on a data bus, - the control parameter is structured as a signal containing objectaddress.code.data- type.data.check. wherein:
  • - datatype defines whether they are control data, object data or log data, - data is the actual control parameter, e.g. temperature, moisture or parameter inquiry,
  • the object when the control parameter is parameter inquiry, the object communicates the actual parameter value to the control unit on the data bus.
  • the controlling of single process parameters is decentralised. After the object having received the predefined parameter or parameters, it controls the process parameter by itself. This makes it simple to provide for sufficiently powerful hardware as an object is only to control a limited number of process parameters. Furthermore, it is simple to change the goal for the process parameter as this only requires that the control unit communicates a new parameter to the object on the data bus. The use of data bus limits the wiring as the same cable may be used for communication with a large number of objects. Expanding the plant with new objects is a simple operation as new objects are only connected to the existing data bus. Even thoughh the control of the single process parameters is decentralised, it is easy to get an overview of the different process parameters by letting the control unit inquire to the desired objects about the actual parameters.
  • An embodiment of the invention comprises a method which furthermore includes that the predefined parameter is communicated to the object as a value which by data processing on the object is translated to a control parameter between 1% and 100%. This serves to standardising the codes so that the communication takes place in a uniform way whereby connecting different objects is facilitated.
  • An embodiment of the invention comprises a method furthermore comprising one or more objects communicating control parameter on the data bus to at least one other object.
  • process parameters that are to be regulated in relation to each other may be readily controlled correctly without involving a central control, as for example the operation panel, by letting one object transmit a control parameter to the object controlling the dependent process parameter.
  • An object may also by itself inquire about e.g. an independent process parameter at another object, and change its own process parameter depending on the reply.
  • An embodiment of the invention comprises a method further including communication without loss of data on the data bus with collision, where
  • the data bus is initiated by providing it with a first predefined voltage
  • a transmitting object sends data on the data bus by attempting to give the data bus a desired voltage level by, in the case of a first type of bit, e.g. 0, attempting to draw the voltage level on the data bus to another predefined voltage level, and in the case of a second type of bit, e.g. 1, to let the data bus keep the first predefined voltage level,
  • the transmitting object measures the voltage of the data bus in order to verify whether the voltage level is at the desired level
  • the transmitting object continues transmission if the desired voltage level is present on the data bus, but discontinues the transmission if the desired voltage level is not present on the data bus.
  • An embodiment of the invention comprises a method, which further includes handling of alarm in a control of a process plant comprising one or more objects where:
  • an alarm object makes an inquiry to other objects about the real size of a process parameter
  • the alarm object compares the returned value with a predefined alarm limit
  • the alarm object issues an emergency order to the object in question.
  • An independent alarm object may thus operate independently of the single modules, so that even a total breakdown of one or more objects will not prevent the alarm signal to be detected. If the alarm limit is reached for a given process parameter, the alarm object communicates an emergency order to the object concerned. The alarm object is thus not directly involved in the controlling of the single process parameters, but leaves to each single object to correct the process parameter by transmitting an emergency order.
  • the alarm object may advantageously be coupled to signal transmitters so that manual intervention may be ordered. Several alarm objects may be coupled for ensuring alarm even thoughh one alarm object is out of service.
  • the object is supplied a voltage which is considerably greater than necessary for driving a processor in the object
  • a control lamp is placed with the possibility of being short-circuited by an electronic switch, e.g. a transistor, in series with the processor of the object in the part of the circuit where the voltage is substantially greater than necessary for driving the processor of the object,
  • an electronic switch e.g. a transistor
  • the object turns off the control lamp by closing the electronic switch.
  • This method is particularly advantageous when there are several objects on the same data bus as it reduces the power consumption by using control lamps.
  • Other power consuming units may advantageously be supplied in the same way as the control lamps.
  • By using a higher voltage for the object it will also be possible to use a higher voltage on the data bus which makes the communication less noise sensitive.
  • An embodiment of the invention differs from the prior art by including an object for a process plant, where the object includes a processor, data communication means, inputs and/or outputs for reading and controlling a process parameter and a predefined object address.
  • An embodiment of the invention differs from the prior art by including an object including means for receiving standard codes with associated parameter value via the data communication means and for changing a parameter in the object, e.g. the real value of the process parameter, the goal for the process parameter or an alarm condition.
  • An embodiment of the invention differs from the prior art by including an object which includes means for transmitting standard codes with associated parameter value via the data communication means reflecting a parameter in the object, e.g. the real value of the process parameter, the goal for the process parameter or alarm condition.
  • An embodiment of the invention differs from prior art by comprising an object which is supplied with a voltage that is substantially higher than necessary for driving the processor of the object, and where the object includes a control lamp supplied with power in series with the processor of the object.
  • the power consumption of the object is largely not dependent on possible control lamps.
  • This is particularly suitable as it is desirable to carry conductors for data communication, alarm condition and power supply jointly. Since the cable is preferably to have as small dimension as possible with regard to price and ease of assembly, this will demand a low current in the cable. Furthermore, the possibility of communicating with relatively high voltages on the data bus is achieved, whereby the noise sensitivity is reduced.
  • An embodiment of the invention differs from the prior art by including an object where the object includes an output for power supply to a unit reading or affecting the process parameter.
  • this unit has a sufficiently small power consumption, such an output will make it very simple to install new units for controlling process parameters.
  • the cabling will be reduced to the cable for the object, as there will be no need for separate power supply cables.
  • An embodiment of the invention differs from prior art by comprising an object where the object comprises an alarm input, means for preventing change of a parameter in the object when the alarm input is in a pre-defined state.
  • An unintended change may e.g. occur by a manual mistake or a noise pulse.
  • the alarm input is connected to a separate conductor the condition of which may be changed. Then is will be suitable that the condition only can be changed by direct intervention from the user so that mistakes in software, processor or other electronics are not given any possibility of changing critical parameters.
  • An embodiment of the invention differs from the prior art by comprising an operation object, the operation object comprising a processor, data communication means and an operation panel.
  • the operation object comprises means for manually selecting and transmitting standard codes with associated parameter value via the data communication means, and for receiving and displaying received standard codes with associated parameter values on the operation panel.
  • the operation object shares many properties with the object which will make cheaper the production and provide many of the same advantages that are associated with the object, e.g. easy integration and cabling.
  • the operation panel is selected both the object or objects to be communicated with and different parameters from the objects are transmitted or received. All the objects may be operated from the operation object so that a total overview from a single place over the whole control of the process may be provided.
  • An embodiment of the invention differs from prior art by including an operation object where the operation object is supplied with a voltage, which is substantially higher than necessary for driving the processor of the object, and where the object comprises one or more control lamps supplied with power in series with the processor of the object.
  • An embodiment of the invention comprises use of an operation object as described above for controlling one or more objects as described above according to a method as described above.
  • the problem may be solved by assuming an object oriented view. This means that within a industry it is mapped which functions there are to be in order that a control may function. Examples of functions are: • Start/stop/speed and monitoring of a belt conveyor
  • Such a unit is called an object.
  • the object thus performs the desired function on the basis of the properties, methods and events belonging to the object, and their settings. Thus there may very well be several objects for the same function where some are more able than others. However, there is a certain minimum which the object must be capable of.
  • the control may now perform its task by giving general instructions to the associated objects which now by themselves provide for their execution. Instructions are always delivered as a value between 0 and 100 %, even also when an associated object only has ON/OFF properties. In this way, the control is always to give the same instructions irrespectively of the kind of object associated therewith.
  • a belt conveyor is to run with a certain speed depending on the previous belt. If too much comes on the belt, the speed is reduced and compensation is to be made. Start and stop of the belt has to occur softly with certain periods of time. In case of failure and overload, alarm is to be set off, and an alarm lamp is to flash at the belt. There is a minimum and a maximum speed for the belt out of con- sideration to the material.
  • the speed control of the belt may be with frequency control, with DC motor or with a mechanical variator. They all require different PLC programs, control signals and different structure of the switchboard.
  • There will be a speed sensor on the belt which is connected to the PLC via the switchboard. There will be a connection from the contactor of the switchboard and to the motor of the belt conveyor. There will be a connection so the alarm lamp may flash.
  • an expression for the belt speed is defined in general.
  • the control transmits the desired speed, and the object conveyor belt attends to maintaining this speed.
  • Min and max values are located in the object itself, and so does the speed control and the alarm lamp.
  • the only connection between the control and the object thus become a data line.
  • the control regularly transmits the speed requirement via a certain code. If the control wants to know the actual speed, or another of the control parameters, it may ask via certain codes. These codes are common to all object of the class belt conveyors. This is also the case with the data format.
  • the operator or the electrician may communicate with each single object via the operation panel of the control. He may set the object to manual mode and set the speed to a certain value. Now he can check whether the object reacts correctly. If this is the case, he has to find the problem in another object. If it is not the case, he may concentrate on finding the failure in that object. Note that he has not operated the PLC yet. He has only selected one object and tested its reaction to a control signal.
  • the Control Panel is a panel of the Control Panel
  • the solution to a new demand from the market may also be a new object, or just expanding with a new method, property or event for an existing object.
  • the changed object may still be used instead of the older objects as it just has something added. This reduces the spare part stock.
  • an object many years old may still be used in a new control as long as its properties etc. suffice. Recycling is therefore realistic with the environmental advantages implied therein.
  • the control may become a control panel and the object in the following.
  • the control panel itself consists of some buttons, some display and a couple of data lines. This makes it cheap, and the customer may pay for having a spare part in stock. Also, it is easy to make panels with another outlook, so that individual firms may differentiate on outlook and possibly operation. The real know-how is now located in the settings used in the object for the different tasks. Integrated Objects:
  • Discrete Objects In some cases, the object wished to be viewed is not available. The object may then be build the object with other objects. This will most often require that the objects have an inherent possibility of linearising. It may be a table converting the control signal from outside to another internal control signal. If a spindle motor e.g. has to be on 10% when the control signal is 30%, this has to be indicated in a table or a formula for a graph. The table is the most user friendly. An example illustrates this:
  • the table is part of the documentation which the maker of the conveyor belt provides. All code oversights are gathered in one section in the documentation binder. Besides that, the maker of the conveyor belt provides an electric connection as shown in Fig. 1. All electric connections are gathered in a section in the documentation binder. The coupling of the objects is shown in a cable diagram which also contains suggestions for object numbers. Fig. 2 shows an example of this. Finally, the simple control pro- gram is added to the control unit (the PLC) in the binder. The documentation is then complete. The work with this is a fraction of the present work where electric diagrams and switchboards are drawn up through many days.
  • the operation interface is to have minimum the following possibilities (buttons):
  • Data Data for the selected object and code may here be changed
  • Section Here the section/zone, where the function or the object is located, is selected. If only one section exists, the button may be omitted.
  • the button may also be fields on a display where e.g. a mouse may activate the field.
  • Code and function may also be translated to clear text if the display allows this.
  • buttons for changing values e.g. + and - buttons, or numerical keyboard.
  • Fig. 3 shows an example of a control forming part of object oriented control.
  • the code oversight for the crusher (Table 4) is found. At the top it is seen that it has object number 8.3. Now, the object button is pushed and with + and - buttons until right Data display shows 8.3 (see Fig. 3). From the code oversight is seen that the protective circuit switch current is code 68. Now, the Code key and the + and - keys are pressed until Code display shows 68. The Data display to the right will now show the actual value. If valid data do not appear, the selected object does not have this code. If no data comes, the object or the data network is faulty.
  • the system also enables an improved possibility of manual control.
  • a unit showing all objects and their actual value and state of operation may be made.
  • the unit may also be portable so that it may be take along to an office or out to one of the objects.
  • the same unit may be used in all control systems as it only shows the created objects and associated functions and their values.
  • the unit may also be made so that it sends data to teletext pages of a TV. The user may then, with the remote control (and during the commercials), see how the condition of the control is.
  • 3 control lamps Line, Send and Error are used.
  • a green lamp is lit if the line is high, i.e. if the line has connection and there is voltage on and will therefor flash when there is traffic on the line.
  • a yellow lamp is lit when the objects transmits data. If data are not correctly transmitted, the object will resend within a short period, and a highly flashing yellow lamp will therefore indicate that there are problems with discharging data.
  • a red warning lamp is lit when fault exists. If the data line is low over a certain time, the error lamp is lit as a sign of the object is supplied with electric current but is without any connection with the other objects. If there are several objects with the same number, the Error lamp flashes rhythmically over a certain period of time. If the Error lamp is lit and if there is communication, one may ask for the cause via an operating panel.
  • 24 N is to be supplied together with the data line.
  • Power supply to objects with small power consumption may advantageously be made centrally, and an uncomplicated voltage is 24N DC.
  • the drawback with 24N fluctuation is a greater energy consumption if the driving impedance is to be e.g. 50 Ohms. With the low speed on the data line, this provides possibility for the drive impedance not to be equal to the impedance characteristic to the cable. A value of 2200 Ohm will be a fair compromise. With regard to noise considerations, the cable should be shielded.
  • Object number 0 is reserved for broadcast, meaning that all have to react to this. Power Generator as Pull-Up
  • Output voltage is 24N and the capacity is 0.5 ⁇ F.
  • the current is thus 10 mA at low, and the power generator is given the same value.
  • v(t) 1/C x i x t, where C is capacity and i is current.
  • the solution with the power generator may thus handle almost 3 times as long cables as with a pull-up resistance. Note that usual pull-up resistances may be used until the cable network become extended so much that problems arise. Then a unity with a power generator may be inserted to solve the problem.
  • the data line (first version called the VE bus) therefore consists of following elements: a shielded cable with 4 conductors. One of the conductors is thicker than the others. There is +24 V to carry the large current.
  • the 3 thin conductor are named Di, Do and Al and function as indicated above.
  • the display has a large copper cross- section and is therefore used a common minus/return. In order to facilitate the work of the electrician, there are used different colours with a symbolic value:
  • Code/Data Access All the objects have a code/data table. All properties and methods are associated with a certain code. Upon enquiring on the object with a code, the object returns object data corresponding to the actual value of the property or the method. This also means that any apparatus that may transmit data as described under the protocol, may set and read an object, both present and possibly new future ones with new functions.
  • Al The alarm system keeps this wire on 24 V whereby all alarm settings are locked.
  • Al In order to change an alarm setting, Al is to be kept low while the value is read by the object affected. Is the value low, this is a sign that changes are allowed.
  • Al may be brought to low in several ways.
  • the operating units may be designed so that pressing the button for data change results in a low Al line. This has to occur around the MCU in order to avoid that it can do this by mistake.
  • Fig. 4 is shown a diagram, e.g. of a circuit for controlling Al. Here it is seen that there is connection from the Data button to the inverter 40106.
  • BC337 receives current via the resistance of 22k. The current is amplified, and the Al line is drawn low.
  • the resistance of 2M2 performs a time delay together with the condensator 0.33u. The time delay is to be large enough that the order can be processed by the relevant object in time.
  • Another possibility is to insert a key switch.
  • the Al line is laid to 0 Volt, and there may be recorded in all alarm objects.
  • the switch is turned back to neutral position, and now changes cannot occur.
  • the key switch may also have third position where it lays the Al line to + 24 V.
  • Common Minus/Return May Give Rise to Problems, if the objects are connected to different earth conductors with different voltage. In mountain areas where it is difficult to get earth connection, the neutral wire is often used as protective conductor. The problem may be due to the occurrence of different voltage. If they are now connected with a relatively small cable, there will run a strong current in the return wire. This may imply disturbances in the communication. Therefore, the objects and the power supplies are thus adapted so that they are not directly connected to earth. Instead, con- densators for high frequency earth and PTC for forming an average level are used. The method is shown in Fig. 5.
  • table 5 shows universal codes.
  • Table 6 shows units determined for the technical control code 48.
  • the objects may also have a built- in switch locking change of settings. If the switch is pushed to Set, one may change the properties and methods of the object. If the switch is set back again, the object will not accept changes any more. Hence, they are protected.
  • a saving possibility is to utilise the voltage loss from 24V to the normal 5 V of the MCU. This may be done as shown in Fig. 6.
  • the base on BC546 is zero, no current runs in BC546.
  • no current runs in BC558 either, whereby the current to 78L05 regulator and MCU is forced to run through the light diode, causing it to be lit.
  • Danfoss CI110 may suffice with 100 mA, but with many objects this will, however, mean a large current.
  • a control lamp is desired for showing that the contactor has been pulled.
  • Light diodes for 100 mA are not available, and the voltage loss of about 2V may be critical when connecting. Instead, the light diode is inserted in series with the one-way diode, whereby it only receives the 33 mA and simultaneously it does not steal voltage from the contactor coil. The principle appears from Fig. 7.
  • 24V motors are large consumers of current.
  • a strong spindle motor may easily have a consumption of 4 A. This rapidly induces large voltage drops in the cable between the power supply and the motor.
  • DC motors have the beneficial property that the tractive force (the torque) is proportional with the current. And since a DC motor with a consumption of 4 A has an inner resistance under 2 Ohms, only 8 V is necessary for it to run. However, it is slow but in applications where this is not a problem, one may advantageously transform the 24V to 8V.
  • a buck converter may be used which with a composition of MOSFET transistors, Schottky diodes and iron powder cores attains an efficiency of 85-90% with obligatory noise suppression.
  • the inductance of the motor is thus not used, and there is not extra wear on the brushes.
  • thinner cables may be used, or motors may be controlled over greater distances.
  • the motor is allowed to stop and wait if the voltage on the supply is too low, e.g. 20V.
  • the current in the supply cable is reserved to the objects that disconnect as the last.
  • the temperature sensor is to measure the air temperature and to transmit it when asked on code 48.
  • the temperature sensor may be analogous or digital.
  • a digital LM74 is used, communicating with the MCU via a serial bus.
  • the sensor may be set to manual via code 01, whereby it no longer responds to the measured temperature.
  • a time-out for manual setting is inserted.
  • a new order via code 01 postpones the time-out period.
  • Fig. 8 the circuit 81 for communication on the data bus and the processor, here an MCU 82, is seen.
  • the sensor As this speed is in the range 0.5 to 3 m/s, the sensor has to cope with this. Stable air is filled with dust, contains ammonia, and is regularly disinfected and washed. This excludes traditional methods like wind wheel anemometer and the hot wire method. The problem with zero point operation is also great as the sensor may be in position for several years without service. Instead, relative temperature measurement is used. A temperature sensor as described above is added a heater. Both are encapsulated in re- sistant plastic. An MCU may read the temperature and steplessly control the power in the heater.
  • the temperature is measured without heat addition.
  • the value is stored, e.g. 28 degrees.
  • heat is applied, and the heat is regulated so that the sensor achieves and keeps a surface temperature of e.g. 10 degrees. After some time, the sensor has become 38 degrees.
  • the supplied power is stored, e.g. 300 mW.
  • the heat is turned off, and the sensor cools for a sufficiently long period. Then it is repeated.
  • the supplied power expresses the air speed, since a great speed cools strongly, why greater power is to be supplied for maintaining the overtemperature.
  • the correlation has previously been laid into the MCU as a table, and the corresponding air speed is calculated and provided at inquiry.
  • Dust deposition on the sensor will reduce the cooling. This will correspond to a lower speed. In practice this will mean that if dust cleaning 4 times a year fails, a fail message will be given off at some time, even thoughh the failure is not real. This prevents a passive emergency function.
  • a deficient heater will cause the MCU to supply maximum voltage and hence believe that the speed is too high. At the start of the heating period it is therefore checked that the sensor really gets a heating.
  • the sensor may also be equipped with a code indicating maximum temperature, where the monitoring goes from temperature to air speed.
  • a code indicating the lower limit for the air speed If the measured temperature exceeds maximum temperature and the measured air speed is lower than the lower speed for the air speed, the emergency sensor transmits a state of emergency and calculates a relative deviation to be changed on the controlling objects.
  • the problem is just that the system is not independent. A disturbance may theoretically provide a transmission changing maximum temperature to a very high value and therefore in reality disconnects the monitoring. This may occur even though there is a check sum in the protocol. Therefore, the emergency sensor may read the Al line, and change of the settings of the emergency sensor may only take place if the alarm line is low.
  • Damper motors are used for positioning something. A universal way is to control ac- cording to 0-100%, where 100%) e.g. is defined as open state. As the damper motor control has built in intelligence, it is obvious to introduce some new methods.
  • the motor control has four buttons:
  • Transformation of the voltage from 24 V to e.g. 8 V is mentioned in the introduction. If one has a buck converter, it is also obvious to use it for soft start whereby large pulses are avoided. And if one has variable voltage to the motor, it will be obvious to make a proportional band around a desired position so that the speed decreases, the closer the motor comes to the desired position. If integration is also used, the motor is controlled quite precisely on the desired position.
  • Adjusting the working range of the motor may be performed by pressing simultaneously the Stop and Open buttons for some seconds when the motor is in the 100%) position. In the same way, the 0% position is determined by pushing Stop and Close buttons for some seconds while the motor is in the completely closed position. It is thus possible to adjust the motor while you are standing right beside it.
  • the values are stored in the memory and do not disappear by power failure.
  • a potentiometer is used for determining the position of the motor.
  • spindle motors with long travel as known from stables, where the walls are a curtain. If the motor is equipped with an impulse switch giving a number of pulses per revolution, the object can count these pulses.
  • the object Since the object also knows the direction of the motor, it may count up if the motor is moving towards 100%, and down if the motor is moving towards 0%. If a power failure occurs during operation of the motor, pulses may be lost. Therefore, the object is provided with an energy reserve that may supply the MCU until the motor stops. While this energy reserve is consumed, counting is continued. When the reserve is used, the counter is moved to the part of the memory that remain after a power failure. Due the small power consumption, the energy reserve may be a condensator of lOOO ⁇ F.
  • motor voltage and max. motor current are Other properties.
  • motor current is over the limit for a certain time, we are speaking of overload, and the motor is stopped. Then, there is waited some time before a new attempt is made. It may e.g. be the case with a curtain which for periods is pressed so hard against the wind that it cannot be drawn up without destroying cords and cord wheels. Here, the object will try again, and if the attempt is made in a period where the wind is weaker, success will appear.
  • the object Since the object has a buck converter, the supply voltage to it may also be an unregulated voltage. Therefore, the object has two terminals: + 24V from the VE bus and + 24-48 V to the buck converter and thereby to the motor. If one does not have a local power supply, the two terminals are interconnected with a short wire. Many of the features to be controlled by the damper motor are non-linear. This may give problems with the control which may be to excited in one working range and too slow in another. If the object is provided with a table, the non-linear may be changed to something linear. The table is seen in codes 10 to 20 in Table 7.
  • the object is controlled as normal with a control signal of 0-250, corresponding to 0- 100% exhaustion.
  • a control signal of 0-250 corresponding to 0- 100% exhaustion.
  • a measuring wing measuring the real exhaust.
  • the object has connection to a measuring wing, and the object will now attempt to get the measured value to be in accordance with the control signal. If the object performance is indicated as 10000m 3 /h, and the control signal is 40%, the damper motor will work until the measuring wing calls 4000m /h.
  • Table 8 shows properties, methods and events for a VE132 exhaust object. Relay Control
  • the object has the operating buttons: Aut
  • the relay operates according to orders from outside received via the data line Off
  • the relay is off
  • the relay is constantly on
  • the object may be set to work ON/OFF or proportional in time. If proportional in time, there are three other properties: Cycle time, minimum on time, minimum off time.
  • a contactor may be inserted whereby 3 -phase equipment may be controlled.
  • the tasks could be electric heating, lighting, motors with built-in protective circuit switches, pumps with built-in protective circuit switches etc.
  • Motor Control Motors may be single-phase or triple-phase.
  • the object is identical with the relay control, but with power transformers for measuring the motor currents.
  • the exceeded amount is added to a variable.
  • the exceeding is calculated as relative exceeding in 2nd power. If the current is under maximum motor current, it is subtracted. If the sum of exceedings becomes too great, too much surplus heat has been deposited in the motor, and the relay/contactor is released and the motor stops. New reconnection may only occur when a certain cooling time has passed. Reconnection may occur automatically or manually by pushing the button.
  • the disconnecting value and the cooling time may be set. If the motor works under easy conditions, it may be allowed to disconnect some time before in order to achieve better protection. Instead of the contactor, one may use solid state switches like triacs.
  • the state of the object is also to be stored in case of power failure so that reconnection cannot occur after a short-time power failure.
  • Fig. 9 shows an example of the structure of a 3-phase motor control. It appears that the motor current is transformed to a voltage with neutral at half the supply voltage for the MCU. The MCU transforms the voltage to a number with reference in this artificial neutral point. The deviation is accumulated in a variable, and at regular intervals there is calculated an average expressing the magnitude of the current. By very large currents, the power transformer will go into saturation, and the measured current becomes slightly less than the maximum value. The power transformer is therefore to handle the start current of the motor without being saturated.
  • the relay may be allowed to fall off, if the task of the objects is not critical, in order to save current from the back-up batteries.
  • VE bus Adaptive MultiMediaCard
  • the data converter is equipped with three control lamps:
  • the protocol between the data converter and the PC it may be determined by a bit which data line is to receive the actual transmission.
  • the system has an object associated with it for taking care of the following tasks: Alarm Wrong values, objects are not responding
  • the emergency sensor may give orders if fault occurs in the normal system. But if the system consists of several sections with each their objects, the emergency sensor will produce emergency control of all objects and thereby disturb sections where the operation is OK.
  • the alarm object receives information about which emergency sensors are associated with which sections. Then information about which objects are to be acti- vated in case of an emergency condition.
  • the alarm object is to use two informations from the emergency sensor: Temperature and air speed. Therefore, both code 48 and code 50 are used. If the limits are exceeded, both alarm and emergency condition/emergency opening are released. Emergency condition prevents the activated objects from going towards 0%.
  • Emergency control is a relative control.
  • the transmitted control value is to be added to the actual value of the object. The example in Table 9 shows how.
  • Alarms are universal. There is specified: Which object The object number, e.g. 55 Which code The code in the object to be checked, e.g. 49 Over/under Whether alarm is to be released at exceeding or going below
  • the alarm object also may handle future objects which were not provided when the alarm object was manufactured.
  • Alarms may be formed by connecting bells, sirens, or phone call machines to one of the alarm outputs which are relay switches free from potential.
  • the power for sirens and bell may be taken from + 24 V of the VE bus.
  • Logging may advantageously be made on a PC, but in some cases a PC is not sufficiently reliable. It is commonly known that a PC may stop or does not start correctly after power failure. Therefore, a logging object is provided in the system.
  • the log object may be set to log a certain value in a certain object with certain intervals.
  • the log object has a real time clock used for chronological determination of the loggings.
  • the data logged are stored on the same medium used by digital cameras: Flash RAM.
  • time is indicated as a relative value in relation to time loggings.
  • the log module may be set up to log all alarm and emergency condition activities so that a failure situation may be analysed later.
  • Fig. 10 shows the general structure.
  • a relatively cheap MCU MC68HC908GP32 is connected to the two data lines of the VE bus. Via three latches, the address is set up to the flash RAM, and data are recorded or read immediately.
  • relay object controlling an electromagnetic valve.
  • the relay object may be placed in immediate proximity of electromagnetic valve and water conduit. Therefore, with the on and off buttons it is easy to check whether the plant is working as supposed. After finish of the testing, the object is reset to Aut.
  • Cooling may be spray cooling controlled proportionally in time. Therefore, here is used a relay module, either 1 -phase or 3- phase.
  • a pump By cooling where water trickles through a pad, a pump has to be controlled. It may be a motor control as well as a relay object. However, there are considerable improvements associated with making a real cooling object: The object can be expanded by connecting electrodes in the water reservoir, whereby the water level may be controlled by an electromagnetic valve. If a motor is also connected for emptying the reservoir, the following advantages maybe achieved:
  • Bleed off via the emptying motor may be established by opening a little from time to time.
  • the water level is determined very precisely.
  • the two other electrodes may be used for conductivity measurement, and bleed off may occur based on a real measurement and not as an assumption.
  • the control form with low and normal speed may be used.
  • the low speed is determined by several factors, but will often be in the range 25 - 35Hz, the normal being 50Hz. Therefore, a stepless regulation until e.g. 35 Hz is to be used, after which time modulation is performed between 35 and 50 Hz.
  • the 35 Hz are typically formed by a frequency control controlling a 3 -phase motor.
  • Fig. 11 shows the diagram for an arrangement which may frequency control a single phase motor with very simple means.
  • the supply voltage is 3 x 230/400V.
  • the diodes form a full bridge 3 -phase rectification, which means that the voltage over Tl and T2 will vary between 488 and 563 V.
  • the curve is seen as the uppermost curve in Fig. 12, designated differens.
  • the motor current runs back to the neutral conductor, it is the positive voltage, which is available when the motor is to have a positive voltage, and correspondingly the negative voltage when the motor is to have a negative volt- age.
  • the actual voltages are seen as the curves Plus Volt and Minus Volt in Fig. 12.
  • Fig. 12 is the required voltage for 35 Hz shown also as the curve Res. Ul volt. Note that in some places it lacks a little in order to be a perfect sine curve. It is where the positive or negative voltage cannot suffice. The small irregularities will be evened by the inductance of the motor and will therefore not have any significance.
  • the voltage is also to be lower, and the irregularities correspondingly less.
  • the current is not to run back via a totem pole, whereby the heat loss is halved.
  • the motor is coupled to one of the three phases and thereby receives the current by-passing the converter. Therefore, there is no loss when full power is demanded. If there are several motors on the task, they may be distributed on the three phases at normal operation so that one will always run if there is power on one phase.
  • harmonic currents in the network there are not any problems with harmonic currents in the network either.
  • the current in the phase is 34.3%. If the 3rd harmonic current is e.g. 3 A when operating at 35Hz, this will only count as 33% since the current at 50Hz will be 9 A, and this will be sine shaped.
  • FIG. 3 shows an example of an op- erating panel.
  • Buttons for code and data are seen.
  • the display above shows the selected code and opposite the data button the associated data.
  • the buttons function and object are seen. Function is discussed in the section concerning method. If function or object is pressed, the display above the function buttons shows the actual function, and the display above the object button the associated object.
  • Fig. 13 shows an example of a structure. Above to the left is seen the control of the A 1 line. To the left drive and input for the two data lines. An operating panel is to have access to both data lines since it has to get information from the sensors as well as to transmit messages to the controlling objects. Note the two pull-up resistance of 2200 Ohm. They keep the data line high. Lowermost, at the middle, is seen an SMPS trans- forming + 24V to + 5 V. Here, there is used an SMPS since the current consumption from the display is large. To the right, lowermost, is seen an EEPROM mounted in a socket. By means of this, one may make a copy of the whole setup and put it into the board. If an accident occurs, the setup is to be read into a new operating panel. At the top all the operating buttons are seen. To the right display and display drivers where multiplexing occurs. Since the MCU cannot take care of details (they are moved out into the objects), it has time to perform this task.
  • the power supply is an object itself with properties, methods and events.
  • the power supply transforms the mains voltage to a voltage of 24 - 30 V.
  • a back-up battery may be connected to the power supply whereby it becomes charged. In case of power failure, the battery will provide the power needed.
  • the object will have two fuses for 24V, whereby a short-circuit will not render all ob- jects without power.
  • normal voltage and final charge voltage maximum current at output as well as charging the battery. By overload, the voltage is reduced so that the current is kept constant. If the voltage goes too far down, an alarm is given. This is also the case if the mains voltage disappears and the battery continues to supply the objects.
  • Table 10 shows an example of methods, properties and events for a power supply.
  • Conveyor belt 1 function 31 Moving slag from silo to crusher Object no. 14.
  • the belt conveyor is allocated object no. 14. A.
  • the belt conveyor can only run one way as minimum is 0. Greatest speed is 5000mm/s, but limited to 1000 mm/s. At start, 4 s is used for maximum speed, by stop 5 s to stop.
  • the regulation is PI, and the tractive force in the belt is limited to 70% of the allowable.
  • the belt will run according to code 48, if code 32 is above 100. Otherwise, they will run according to code 32 (manual control), which is in % of the allowable range.
  • the belt conveyor is assigned object no. 15. A.
  • the belt conveyor has not speed regulation since maximum speed cannot be set.
  • the belt speed is 630 mm/s.
  • the regulation is proportional in time with an interval of 20 seconds.
  • Min. running time is 2 s, and min. stop time is 1 s.
  • the belt will run according to code 48 if code 32 is above 100. Otherwise, they will run according to code 32 (manual control) which is in % of the allowed range.
  • code 48 is over 50% of maximum speed, the belt will run constantly, if code 70 is set to 0 (on/off).
  • Crusher 1 in function 101 Crushing slag supplied by belt conveyor 1 Object no. 8.3 Code table:
  • the crusher is assigned object no. 8.3.
  • the crusher has not speed regulation since maximum speed cannot be set.
  • the speed for the crusher is 1400 rpm. There is 10 s operation in star before switching to delta when starting.
  • the crusher will run according to code 48 if code 32 is above 100. Otherwise, it will run according to code 32 (manual control) which is in % of the allowed range. When code 48 is over 50% of max. speed, the crusher will run continuously.
  • the crusher does not have interval operation. Table 5

Abstract

L"invention concerne une commande d"installation de traitement comprenant un ou plusieurs objets, ces objets possédant des moyens de réception de codes standards avec des valeurs de paramètres associés, via des moyens de communication, ainsi que des moyens de changement d"un paramètre d"un objet, par exemple, la valeur réelle du paramètre de procédé, la valeur à atteindre pour le paramètre de procédé ou une condition d"alarme, l"objet comprenant, en outre, des moyens d"émission de codes standards avec des valeurs de paramètres associés, via ces moyens de communication, reflétant un paramètre de l"objet, par exemple, la valeur réelle du paramètre de procédé, la valeur à atteindre pour le paramètre de procédé ou une condition d"alarme.
EP01999864A 2000-12-06 2001-12-06 Commande d'une installation de traitement comprenant un ou plusieurs objets Ceased EP1346491A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DKPA200001831 2000-12-06
DK200001831 2000-12-06
PCT/DK2001/000812 WO2002046850A1 (fr) 2000-12-06 2001-12-06 Commande d"une installation de traitement comprenant un ou plusieurs objets

Publications (1)

Publication Number Publication Date
EP1346491A1 true EP1346491A1 (fr) 2003-09-24

Family

ID=8159889

Family Applications (1)

Application Number Title Priority Date Filing Date
EP01999864A Ceased EP1346491A1 (fr) 2000-12-06 2001-12-06 Commande d'une installation de traitement comprenant un ou plusieurs objets

Country Status (4)

Country Link
EP (1) EP1346491A1 (fr)
AU (1) AU2002220532A1 (fr)
CA (1) CA2434092A1 (fr)
WO (1) WO2002046850A1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2578619A1 (fr) 2007-01-31 2008-07-31 Conception Ro-Main Inc. Systeme de controle de naissance de porcelets

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4819149A (en) * 1986-05-02 1989-04-04 Owens-Corning Fiberglas Corporation Distributed control system
FI97587C (fi) * 1994-09-09 1997-01-10 Seppo Laine Paikallisverkkojärjestely
US6044305A (en) * 1996-10-04 2000-03-28 Fisher Controls International, Inc. Method and apparatus for debugging and tuning a process control network having distributed control functions

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0246850A1 *

Also Published As

Publication number Publication date
AU2002220532A1 (en) 2002-06-18
WO2002046850A8 (fr) 2002-09-19
CA2434092A1 (fr) 2002-06-13
WO2002046850A1 (fr) 2002-06-13

Similar Documents

Publication Publication Date Title
US5880677A (en) System for monitoring and controlling electrical consumption, including transceiver communicator control apparatus and alternating current control apparatus
CA2134510C (fr) Methode et dispositif pour executer une instruction dans une multiplicite d'appareils de mesure electriques
EP1339153B1 (fr) Dispositif pour connecter un batiment ou semblable à un réseau éléctrique de basse tension
DE10309886B4 (de) Anfügesystem und anfügefähige Geräte zur Datengewinnung, Analyse und Steuerung
CN102576042B (zh) 用以对消费者提供供应装置中若干能量的装置及方法
US20010010032A1 (en) Energy management and building automation system
US4027171A (en) Power demand limiting system
US20110006887A1 (en) Programmable Communicating Thermostat And System
WO1996022541A1 (fr) Detecteur de courant de fuite pourvu d'un emetteur-recepteur radio
DE102009034887A1 (de) Einrichtung und Verfahren zur Bereitstellung einer Energiemenge in der Ladestation für ein Elektrofahrzeug
KR19980701245A (ko) 에너지 관리 및 빌딩 오토메이션 시스템(energy management and building automation system)
DE3640448A1 (de) Verbrauchszaehler
EP3820011A1 (fr) Système de gestion de la charge et procédé de régulation d'un tel système de gestion de la charge
Durocher et al. Application of next-generation motor management relays improves system reliability in process industries
EP1346491A1 (fr) Commande d'une installation de traitement comprenant un ou plusieurs objets
EP2506393A2 (fr) Dispositif de raccordement d'un bâtiment ou analogue sur un réseau électrique basse tension
EP1959133A2 (fr) Installation de convertisseur d'alimentation
US6448747B1 (en) Electricity pod controller device
GB2144566A (en) Remote metering system
CN207123042U (zh) 三相空调智能控制器和智能空调系统
CN208299283U (zh) 一种全兼容在线监控电力箱
EP1448997B1 (fr) Unite de commande de consommation d'energie
CN201726042U (zh) 改进的直流屏
EP2989710B1 (fr) Sistème et procédé pour la fourniture d'énergie électrique
CN214154564U (zh) 一种污水处理厂站设备的监测装置及系统

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20030626

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

AX Request for extension of the european patent

Extension state: AL LT LV MK RO SI

17Q First examination report despatched

Effective date: 20061221

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN REFUSED

18R Application refused

Effective date: 20100609