DE2109922A1 - Tax system - Google Patents

Description

Tax system

The invention relates to control systems that have an electrical Output signal depending on input signals

deliver*

are used for many purposes, such as automatic control of labor or chemical processes. Such control systems are commonly used in conjunction with transducers that determine the magnitude of the parameters relating to the process being controlled and provide electrical signals to be fed into the control system · This processes these signals and provides electrical output signals for control purposes. The invention relates to a control system with a view! of information inputs that provide output signals for a number of control processes. In the control system according to the invention, the data processing takes place digitally on a time-division basis. Apart from the sound of the time-sharing mode of operation of the digital data processing system, the control processes can be independent in the sense that an input information

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is processed from a source and is used to provide an output signal independent of any other input information »It is therefore advantageous« ^{to speak of "control channels 1} *, where a channel with the reception of an input information for supplying the data processing system and for supplying a As will be explained in more detail below, ₉ the channels can be connected to one another for various purposes, so input information can be used in more than one channel or output information can be output One channel can be used as input information for another channel. However, it is advantageous to see the system primarily as "having a number of control channels" which can be operated independently of one another on a time division multiplex using a standard data processing system

According to the invention, a control system with a number of control channels consists of a conventional data processing unit for processing data in digital format. from a number of separate control channels »each of which has a digital memory for storing an input information» an output information and another for owns this channel of relevant information, from a sequential control to the sequential connection the data processing unit with the memories assigned to the various channels and from an algorithm memory, the information for the data processing unit for suitable processing of the input information on the selected channel and for feeding of the processed input information in the outgoing

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memory of this channel delivers <

The system can suitably be designed in such a way that up to KU e.g. 100 channels and each of them are operated periodically depending on requirements · It would also be possible "to process the data in 100 channels in less than a second" but it is as will be explained later _£ often desired, the data were obtained at longer intervals than this to process "uamit noticeable changes in Eingangeinformation and uses can to deliver information about the Veränderungsgesahwindigkeit" the follow-up control is therefore preferably adjustable or voreinatellbar, in order to connect the various channels to the data processing unit at time intervals which have all been suitably selected for the individual cannula

Every channel basically corresponds to a soleplate control. For each channel the input signals can be analog signals, for example an input current "An input current in any given current strength range can be converted by a suitable terminating resistor so" that it _{generates a signal in a standard voltage range, e.g. 0} between 1 and 5 VoIt ₉ ", The Voltage signals can be sampled by switches, eg Peldefl'ekt-Trans is tor er, controlled by the channel sequence control and fed one after the other to a high-speed analog-to-digital converter. The resulting digital signal is then in Enter the memory for the input data of the appropriate channel. Alternatively, each channel can have a separate analog digital converter to store the analog input

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information in digital form at the input data Storage

The output memory of a channel has information in digital 3? Form ₉ which can be converted into analog farm, SoB »a current output, using a digital-to-analog converter, for example, as described in British patent application No. ₀ 29384/69 iet _s in which the digital-analog Urawandhmg effected by v / IRDP that a number is repeated in such a way periodically in a shift register "that each bit of the number appears on the output of the shift register for a matching with the significance of the bit period in appearance. The instantaneous output of the shift register is then smoothed to provide a DC voltage proportional to the number on the shift register and that voltage is in turn converted into the desired Strora output signal

converted «The one for such a digital-to-analog conversion The required sliding door series is complex, it can however a pulse generator can be used to generate the strike pulse series for any number of such digital-to-analog converters to deliver"

If a shift register is used for the digital-to-analog conversion of the output of a channel, it is advantageous; to use a single shift register for each channel in order to store not only the output information but also the input information and all other data that are required for this channel during the process of the register stops? Data transfers to and from the registers _r causes while the figures during their

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normal periodic repetition, where synchronizing information from the sole pulse generator is used »

The digital data processing unit processes the input information using algorithms from the algorithm memory according to the instruction duroh a channel information memory <, The algorithm memory preferably contains algorithms for all normal control tasks, such as SSoBo three-part control with cascade control of the setpoint and feed, ratio * control, and a general advance ~ / Naoheii ~ / Ve * - strength / limitation algorithm. The control data, eB "target values" integral and derived time constants u "sw _p , determined for use with the algorithms are preferably described for the various channels _t as follows "Brought into the memory and stored in it"

Monitoring options can be provided, to monitor the input and output information in the input and output data columns manually operated control devices are provided «

The monitoring options can be operated manually Selection means for selecting a channel and visual display means for displaying input and output information in the unselected channel memory. Means that can be operated by hand are preferably provided « to enter the setpoint and / or other control information in the selected channel memory »For this

number can be provided without control panel »information inputs ₀

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In addition, a digital interface can be provided, can be used to connect other devices ₀ For example, a computer-monitoring added to setpoint ,, 2 © itkonstanten etc adjust, or he can either accept the 4i £ ects control some channels independently or jseluweilig · A setpoint sequence "Steuerun &imnnn" can be provided to control one or all of the setpoints ^ des? other Kens sounded geoäS a given sequence © m «'- / ϊέ ^ am when starting or changing other quickly. S.

A fixed Spato ^ s? vcxed to provide fixed information. Biysikali & uh these fixed memories can be arranged in the same place; they can be prepared for adjustment by the user. For example, the fixed memories for all channels can comprise a single diode socket matrix ₉ which is hereinafter referred to as the channel information memory «This matrix can be scanned in one stage with the successive scanning of the various channels» Socket plate matrix can have a row (or column) of sockets for each channel * These sockets are preferably arranged so that the desired function (2. B ₀ the desired algorithm) is selected for each channel by inserting plugs into appropriately labeled sockets or by inserting corresponding gekennzeiohneter Mehrfachsteoker into a jack _o example, "proportional" can, "integral" and "derived" jacks ₉ can be provided with plugs are inserted in .all three jacks "if a drelgliederige control desired 1st odesr in only one or two Sockets, if only a one «or two-part control is desired *

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Alternatively, a single multifunctional booster (e.g. a Vierfaohbuohse) be provided * in a suitable one Multiple plug is plugged in according to the desired type of control * Similar additional sockets can be used verges ehsa sein »to select other functions, such as e.g. a warning process or a query interval. With such a beech plate matrix, for connection between the channels, e.g. to connect the output of one channel can be used with the input of another channel, connector without.

An intermediate register is advantageously used, which is assigned to the data processing unit, with the complete information from the data memories, assigned to each channel to the buffer the appropriate sequence is transmitted when the data should be processed from this channel. The data processing unit can use this register and a little retention of results to keep the ~ desired processing to be performed, at the end of processing the desired output along with others variables to be remembered "such as the value of the integral expression in a three-part control channel" into the appropriate ones Digits of the swish register is entered <, As a final stage in the processing of a channel, the new contents of the intermediate register are updated to the appropriate one Transfer channel data memory.

Preferably options are provided for "occupied Hold" at the output of each channel, for example by _f that the output voltage is transmitted to a capacitor * of a voltage-current converter is switched to a battery powered power supply in the input ,, manually operable additional

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Possibilities aura raising _or lowering can be provided for manually changing the output »The control panel can have a switch to connect all channels to the charging device so that the output signal can be isolated and maintained in the event of a system failure» Bs automatic gowns should be provided in order to operate this switch through Pehlereroittlungskreiee «

On the basis of the following description of an exemplary embodiment of the invention shown in the drawing this is explained in more detail

1 shows a block diagram of an inventive Tax system,

FIG. 2 shows the control system according to FIG. 1 more in detail,

Fig. 3 in a schematic representation Control panel for the control system according to Figo 1,

FIG _e 4 for the purpose of explanation, the

Scheme of a temperature control sole with cascade operation and

Fig. 5 schematically shows part of a socket plate matrix for use in the control system according to FIG. 1, the circuit for the control soleife according to Fig. 4 is shown.

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Pigο 1 shows a computing unit 10 with an algorithm memory 11 and a channel selector 12 for the successive selection of the channels. As mentioned above, can a large number of channels be provided? z. B. 100 channels «Each channel gives an input» information for data processing and output »control signals or possibly output signals for feeding into other channels» These channels are sohematisoh represented by three pairs of lines 13 »14 and 15, with each pass having an input and an output owns. The input and output circuits are represented by block 16 which includes analog-to-digital converters for input information, digital-to-analog converters for output information and a data memory for each channel. Typically, this data memory is a separate 100-bit shift register for each channel.As mentioned above, this shift register can be used for digital-to-analog conversion, 8 as well as for storing input data, output data and the data required for the respective channel , which is shown in Pig, 5 and will later be explained in more detail later * has monitoring and manual control devices _p which are shown in Fig. 1 at 19 and which serve to display the input data and the output control data and also the setpoint advantageously, the operator has a channel selector, Zo B * pressure knobs ₉ so that it can select any channel and only the information of this channel wirdο displayed, the operator has the ability zm change of setpoints and other information, including direct manual control jedee Off ~ gangs · to be entered Information becomes one tell

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factory and displayed for review before being transferred to the control system. The operator also has the option of "holding" _{0 as described above}

In Figo 2, the control system is shown more in detail · The arithmetic unit 10 is connected by a-referred with 20 "21 Baim with Kanaldatanspeiehern from the <§ & DRSI echematsieh at 22, 23 and 24 are" This ^ iet- sr each include a shift register for storing digital data. Each hybrid memory can also have a dedicated analog / digital converter for converting the analog input information into digital data to be entered in the shift register. In the arrangement shown, however, a single analog-to-digital converter 25 is provided in these? In this case, sequential switching means are provided to connect the various analog inputs to the converter and at the same time pass the digital outputs of the converter on to the corresponding memory. Typically, input signals are streams from remote converters. Each input * current is grounded via a resistor in order to deliver a voltage signal in a predetermined range, e.g. 1 to 5 volts, see below. Transducer 25 transmitted, where it is smoothed with a suitable time constant in order to eliminate possible high-frequency interference «. The analog-to-digital conversion advantageously uses a ladder hold with switches of a register controlled by flip-flops, so that the digital output

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number old the most characteristic bit is first constructed by a series of tests and comparisons bit by bit, then the resulting number is continuously output from the register, if necessary. Each channel also has facilities for converting the digital output data in analog to ₀ For this purpose a generator is provided for generating pulses, as described, for example, in British patent application 29334/69, in order to convert each digit of the number to be converted for time periods which correspond to the identifier of the bit The present output voltage is then smoothed in order to generate a DC voltage proportional to the output information in the shift register, whereupon this voltage is then converted into the desired output current signal Each output is marked with an *. ¹ holding device 2u provided to automatically hold the analog output voltage so that it remains in place if a fault occurs in the main power supply or in another part of the control system, _{or the like}

The calculation unit 10 expediently has a row adder, a collective register and two working registers aufο Ks is advantageous, however, also an intermediate register to be provided, the data of a channel memory required by the processing unit initially via the outer track 20 would be directed to the intermediate register in the arithmetic unit »The arithmetic unit has individually to each part of the intermediate register accesses The sequential control of the channels is via a logical control 36 causes a program

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counter 37 feeds and takes over information from two program matrices 33 and 59 ο The side flow is controlled by a © Bhreneinheit 40 »which directly controls the previously mentioned cash number counter 31» The output of the channel number counter 31 is fed into a channel number decoder 42, the * as explained below, the selection of the channels controlled by use of a Abtastinte rvallmatr ix 43rd The output of this matrix is fed to a comparison device 44 which is compared with the output of a sampling interval counter 45. On a system with 100 channels, the channel number counter can be incremented by a unit every 10 milliseconds using a 100 Hz ear frequency, whereby the sampling interval counter 45 would in this case be incremented every second, ie after a complete sequence of the channel selection sender, to the appropriate control signals give to the logic controller »live the sampling interval ·» matrix nmß »as shown below? Outputs deliver ₉ that indicate in which sequences each channel is to be queried _o It also feeds a © scaling unit 47? in which this information is used together with information from a pen and area matrix 48 to provide the appropriate displays for the control panel. The arithmetic unit 10 performs calculations in fourths from 0 to 100 ^ of the input signal and therefore requires no information from this zero and range matrix 48 «

A digital partition that sohematiaoh at 50 is shown provides information to and from the data lanes and is used to view other digital facilities to be connected ο

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* = 13 -

The channel Ahlen counter 31 sequentially selects the various channels door processing aua and typically includes a two-decade counter with eight output lines, the _β bear the channel numbers in binary encoded decimal form of the state of the counter during a suitable period festgehalten3 for example, 10 milliseconds long for performing the calculations «before switching to the next channel. The channel number in binary-coded, decimal form is fed to the channel number decoder 42 in order to provide outputs on separate lines for each channel in order to operate the channel information memory. These outputs also select the correct destination for transmission to an alarm register .

The channel information memory comprises the sampling interval matrix, the mull and area matrix and a channel - Sunktions-MatriXjWelohe a desk 49 for pluggable Diodes is to allow the operator to determine the type of each channel and each connection between the channels. These The plug-in desk matrix will be explained later with reference to FIG. 5 and is not used for a numerical Define constant for the channel. However, it must indicate which of the proposed algorithms for Every channel is used and is therefore used to directly select one or the other of the algorithms 38, 39 to be hidden for the arithmetic logic control circuit. It also determines in detail which one Parts of the chosen algorithm actually used turn around. For example, it can be proportional and integral control in forward control from one

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- u

select generalized three-part control algorithm «The channel function matrix also determines the connections between the channels. Dica allows the use of set points and Vorwärtusteuerwerten in cascade, as well as intermediates for mutual control · As will be described later, is dia beech panel has 49 output boxes and input books "; connector cords are used to output jacks ^ mn ingangsbucheen each other to connect? if the *; jazig for eiriöd channel is taken from the output of another channel, Dia Hull and area matrix 48 is also operated by Karialssüilen Beooder 42 and provides information that monitoring is required. The channel number decoder 42 also operates the sampling interval matrix 43- «which enables the operator to determine the sampling interval according to the requirements for each channel. This sampling interval matrix can also take the form of a desk for pluggable diodes. This matrix 43 is provided because it can often be necessary not to use all channels during a sequence, eg ₀ not to use all channels every second. The reason for this is that the derived time coefficient must not be more than a few sharks greater than the sampling interval if the fluctuation effects of a measured input are not to be significant, note that the change in the input must be measured during each sampling interval. For this reason, can ea be desirable for some channels? having relatively long sampling intervals »possibly on the order of many minutes.

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3 shows the control panel. This has a set of keys 50 for inputting numerical information, these seeds being advantageously arranged on a tabletop. The panel also has a display unit 51 which has both additional buttons and visual indicators at the top of the display unit A number of visual display elements are provided, which include a channel number "display 52", a display 53 for the measured input, a display 54 for the nominal value, a display 55 for the output and a separate monitoring display 56 "The operator can select a channel for monitoring and to enter the control values by bridging a number on the keys 50 select "whereby the channel selection is effected by actuating a switch 57 * The display 52 enables the operator to monitor" that the correct channel number has been keyed. The Anaoig © 53 then shows the measured input for this channel and the displays 54 and 56 show the control file! which are in the memory of the selected channel «The special Überwackuiigaansej-ge 56 shows information that z, B. the integral time constant, the derived time constant, proportional range, the sampling interval etc. ₀ as selected by a set of keys 58. The control data are changed by pressing the desired number on the keys 50, with the monitoring device 61 checking that the correct number has been keyed in and after which the data is transmitted in that a Übertragungetaste 59 is used, eowia one of three selection buttons 60, depending on whether it is a target value information, an output

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(for manual control), or other ready chamfered by ein®! 38 is selected constant. The control panel also has a set of three keys 62j to select an "automatic control" , "manual control" or "hold ¹¹ " key. that the output of the selected channel is held by the hold circuit 28 described above. Three further buttons 63 are intended for normal operation "only manual control or only hold", and give the operator the opportunity to switch off the control system and hold all outputs, whereby after manual intervention is possible on all channels ο display devices 64 are used to display errors in the control system, e.g. in the power supply, in the monitoring of the computing process or in the data transmission. Warning thresholds can also be provided for the input and output signals by using d The keyboard 50 and the particular monitor 56 can be set. "These alarm signals are preferably indicator lights (not shown) in a flow chart illustrating the process to be controlled." Audible and other alarm devices can also be provided.

It can be seen that the control panel provides the input of numerical data required for control purposes into the memories of the various channels. The way “in which this information and the The input data relating to the process can be made usable in the various control channels

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from the algorithms save from * The algorithms are down? Use of a Buohsenplatte selected and are not controlled from the control panel «For any given procedure it will normally be necessary» to change the distribution of the control algorithms once they have been selected «Fig. 5 shows part of a diode-matrix control panel 70, This control desk has a number of rows that correspond to the various channels and has reference symbols and numbers in the two left-hand columns 71 and 72 to identify the channels columns "If in any row a plug in the column P is inserted _p is a proportional term entered, if it is plugged in a plug in the column I in the Steuemohleife for this channel _P is inputted into the Stöuerschleife an integral term ©, and if a Plug is plugged into the D-pillar, a plug is disconnected in the control panel ith term introduced. The socket plate matrix only controls the algorithm in this regard, while the numerical constants are stored in the shift registers of the various channels. The algorithm section of the Buohsenplatte also has columns that allow a sum, difference, a product and ratio expressions to be used, as well as Voreil-Naoheil algorithms 7? is shown to connect an output column socket of one channel with an electrical column socket of another channel »The socket plate also has columns for the determination of warning signals, control of key intervals and other control functions _a

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The mode of operation of the socket plate can be understood if one looks at the example shown in FIGS. 7ig, 4- Introduces temperature loop at which the temperature of a fluid along a flow path 80 is controlled in the direction indicated by the arrow 81 using a heating element 82 shall be. Mn temperature sensor 83 supplies a measured input for a first channel 84 of the control system 65 "This channel provides proportional and integrity" ■ control with one through the Setpoint set by the operator and its output is used to set the setpoint for a second To deliver control channel 86 »This second channel receives its measured input from a temperature sensor and provides proportional and derivative control, providing an output corresponding to a current lei stungs converter 88 is supplied, which feeds the heating element 82 o

Fig. 5 shows the setting of the socket plate for this control. For the first channel on the plate is marked with TCOl, plugs 90 are in the proportional and the integral column of the algorithm section plugged in · For the second channel, which is marked with TC02, plugs 91 are plugged into the proportional and the derived column. Bas Connection element 73 connects the output of the first channel to the appropriate input of the second channel (in this case the setpoint input). It can be seen that the setting of the desired algorithms has no effect whatsoever Knowledge of computer programming required and can easily be carried out once the control requirements are defined o The individual control channels

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a one-, two- or three-part control can * cascade and forward controls and other algorithms can easily be provided vieraeHo

As mentioned above, the operator can ^ e EEacii the requirements setpoints or other control data enter "The digital partition 50 can be used to set a sequence of setpoints from your external

adjust the programmed control or during dee Um £ ahrens or of completion of the procedure, "

Patent claims:

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Claims (1)

Patent claims: Control system with a number of control channels, characterized by a conventional data processing unit (10) for processing data in digital form _t through a number of separate control channels (13 »14» 15), each of which has a digital memory for storing input information, output information and others has information relevant for this channel, through a sequence control for the successive connection of the data processing unit with the memories assigned to the various channels, and through an algorithm memory (11) _{P of} the information for the data processing unit for suitable processing of the input information on the selected channel and for feeding supplies the processed input information in the output memories of this channel, 2o control system according to claim 1, characterized in ₉ that the sequential control is adjustable or presettable in order to connect the different channels with the data processing unit in time intervals which are selected for the individual channels. 3 «Control system according to one of Claims 1 or 2, for the use of input information in analog form, characterized by an analog-to-digital converter (25) and a switching device that is controlled by this sequence is adjustable to de? Input information with to connect to the analog-to-digital converter successively and to input into this and to the output of the Analog-digital converter in the memory of the appropriate Enter the channel BADOWGINAL - tue - 109840/1533 4o control system according to one of claims 1 or 2 and for use for input information in analog Form, characterized by a separate analog-digital converter / conversion of the input information into digital form and their input into the memory of this channel " 5ο control system according to one of the preceding claims, characterized in that "the digital memory of each channel comprises a shift register" 6 ₀ Control system according to one of the preceding claims, characterized in that monitoring means for monitoring the input and the AusgangsinfoKiaätionen Kanalspeioher are provided. 7ο control system according to claim 6, characterized in that that the monitoring devices are manually operable selection means for selecting a channel and visual display means to display the input and output information of the memory of the selected channel. 8ο control system according to claim 7, characterized in that that manually operable means for entering the setpoint and / or other control information in the Memories of the selected channel are provided, 9 «control system according to claim 8, characterized duroh a follow-up control for the setpoints, around one or all © setpoints or other control constants in one to change the given sequence. - 22 109840/153 3 10 control system according to one of the preceding claims _9, characterized in that a channel information memory is provided which supplied information specified for the various channels '11 »Control system according to claim 1O _9, characterized _9, that this channel information column uafaSt a matrix which is scanned by the sequential control with the successive scanning of the different channels. 12 · control system according to one of claims 10 or 1t, characterized in that the channel format memory has manually operable means for selecting the algorithms for the various channels. 13o control system according to claim 12, characterized in that that this manually controllable means can also be used to connect the output of one channel to the input of another Can be used, Ho control system according to one of claims 12 or 13 » characterized in that the means for selecting the Algorithms comprise a plug-in console matrix in which a row of sockets is provided for each channel, in the plugs can be used to select the desired algorithm. 15 · Control system according to claim 14, characterized in that » that the board has jacks for each channel to select proportional, integral and derivative expressions. - 23 - 109840/1533 16c control system according to one of claims 14 or 15, characterized »that the plug-in desk for each channel has at least one output socket and at least one Has input socket and that Steoker cords (73) are provided are to connect an output of a channel from an output socket on the Steokpult to the input socket to connect another channel " 17 ", control system according to one of claims 14 to 16 _p, characterized in that the jacks for each channel are arranged in a row or column. 18 ο Control system according to one of the preceding claims, characterized in that each channel has a digital-to-analog converter which is connected to the digital memory in order to convert the output information into analog form 19α control system according to claim 18 "characterized that battery-powered holding means are provided which can be actuated for each channel in order to hold the analog output information to hold on " 20c control system according to claim 19 »characterized in that an error detection device is provided, which is connected to the battery-powered holding means to actuate them » 21 .. Control system with a number of control channels " a common unit for processing data in digital form, with a sequence controller, a Channel information store, an algorithm store and a control unit ,, characterized ,, that - 24 109840/1533 (a) the control channels _(13? 14, 15) each informal ion a shift register for lipeieherung the input information f> of the output and the relevant for this channel fiteuerinformation own "that an analog-to-digital converter for converting the analog input data to digital form and to feed them into the shift register ο that a digital-to-analog converter is connected to the memory to convert the output information into analog form, and that battery-operated holding means are provided to hold the analog output information, (b) that the sequential control comprises holding means which successively connects the data processing unit to the memories connected to the various channels and at the same time retrieves information from the algorithm memory in order to process the input data from the selected channel in a suitable manner and the output data to the output memory to feed this channel, (o) that the channel information memory is manually operable Has means of selecting the algorithms stored in the algorithm memory for each kunal in the Channel scan sequence are obtained, (d) that this control unit is manually operable channel selection means comprises, visual display means for displaying the input and output information in the Memory of the selected channel and means for entering the control data into the memory of the selected one Canal. - 25 109840/1533 22o control system according to claim 21, characterized in that that the control unit provides numerical information input unit and a selection device to select the appropriate parts of each memory for input of informationο 23o control system according to claim 22, characterized in that that the selection device means for selecting a Spelo production for target value ~ 2) ia.ten, a proportional range, comprises an integral time constant and a derivative time constant and means which are operable are to get the numerical values of this Kingube unit to enter in the selected memory location «» 24ο control system according to claim 22 or 23 _t characterized in that display means Sindo stubborn / n ^ EIGE of numeric, operable in the input unit values entered manually and means for the transmission of the values displayed on the ausgewühlten provided Kanalapeioher 25ο control system according to one of claims 21 to 24 » characterized in that these manually operable means for selecting the algorithms are one for each channel Plug-in desk matrix include = 109840/1533