AU674608B2

AU674608B2 - Method of parametering a digital voltage regulator

Info

Publication number: AU674608B2
Application number: AU74360/94A
Authority: AU
Inventors: Peter Okanik
Original assignee: Maschinenfabrik Reinhausen GmbH; Maschinenfabrik Reinhausen Gebrueder Scheubeck GmbH and Co KG
Current assignee: Maschinenfabrik Reinhausen GmbH
Priority date: 1993-10-26
Filing date: 1994-09-30
Publication date: 1997-01-02
Anticipated expiration: 2014-09-30
Also published as: FI945016A0; FI945016L; DE4336438C1; JPH07244534A; FI945016A7; CN1106940A; EP0650113A3; EP0650113A2; ATE179806T1; DE59408208D1; AU7436094A; KR950012180A; EP0650113B1; CN1040155C

Abstract

The parameter setting system uses operation of at least one function push-button (6..15) to select and adjust each parameter, with the setting value of each parameter indicated via a digital display (2), with a scroll wheel (1) moved in both directions to index the setting value forwards or backwards. When the required parameter value is reached, the function push-button is released and the parameter value is transferred to a memory, with the display restored to displaying the actual voltage. Pref. the sum of the parameter values held in a read-only memory are compared with the sum of the actual selected parameter values to activate a warning signal when they fail to agree, with control pulse blocking until the selected parameter values are re-programmed to obtain agreement between the compared sums.

Description

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AUSTRALIA

Patents Act COMPLETE SPECIFICATION

(ORIGINAL)

Class Int. Class Application Number: Lodged: Complete Specification Lodged: Accepted: Published: Priority Related Art: Name of Applicant: Maschinenfabrik Reinhausen GmbH Actual Inventor(s): Peter Okanik Address for Service: PHILLIPS ORMONDE FITZPATRICK Patent and Trade Mark Attorneys 367 Collins Street Melbourne 3000 AUSTRALIA Invention Title: METHOD OF PARAMETERING A DIGITAL VOLTAGE REGULATOR Our Ref: 385271 POF Code: 1585/238596 The following statement is a full description of this invention, including the best method of performing it known to applicant(s): -1-

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The present invention relates to a method for the parametering of a digital voltage regulator and to a digital voltage regulator in which such a method can be carried out, especially a regulator for a transformer with a tap selector switch.

Voltage regulators for control of a transformer with a tap selector switch, which is actuated by a motor drive, are described in the publications "Solid-State Voltage Regulator MK20 Inspection Instructions" and "Solid-State Voltage Regulator MK20 Operating Instructions" issued by Maschinenfabrik Reinhausen GmbH of Regensburg, Germany. The drive control of the motor drive, which operates on the principle of stepped switching, by a control pulse effects actuation of the tap selector switch and thereby a voltage change o* the transformer by one step. The control pulse is issued as a control command "higher" or "lower" by the voltage regulator to the motor drive if the actual voltage value differs within predetermined limits from a desired voltage value. For parametering, i,e. for setting of target values and other magnitudes, for example target voltage value, delay time, sensitivity, etc., precision spindle potentiometers with scales are used. The indication of a regulating deviation is provided by way of an indicator galvonometer.

Electronic, microprocessor-controlled digital voltage regulators are also known for the same purose. For the parametering of such digital voltage regulators, the afore-mentioned potentiometers with scales would additionally have to be provided with downstream analog-to-digital converters connected therebehind.

-2- This is technically possible, but of little advantage, because potentiometers have a limited setting accuracy and also a long term instability and thus cannot exploit important advantages of digital techniques.

For the parametering of such digital voltage regulators, it is known, in the case of devices with a simple alpha-numeric indication, to display and process individual parameters in a circular sequence after actuation of a selector key. Since measurement values of the actual voltage or percentage deviations 10 from the desired value are permanently indicated in most cases, the 0oo* .".display must be switched over appropriately to the parametering process. A targeted, delay-free interrogation of a certain selected parameter is riot possible.

Moreover, it is known to use a numeric keyboard for 15 parametering. The individual parameters can be addressed and displayed by way of a code selected at the keyboard. In that case Sit is disadvantageous that the operator requires a code list containing the association of the selectable parameters with the t o. corresponding codes. Such a code list i hardly practicable, in 20 view of the large number of necessary parameter settings present in a complex regulator and can easily be lost, if account is taken of the long intervals between checking or resetting intervals. Thus, such a list is often not available to the operator when it is needed.

Finally, it is known to provide, for each setting of the variables, a multiple BCD-coding switch. However, this is expensive and has a relatively high space requirement.

a- pll -3 Apart from these technical aspects of the parametering of digital voltage regulators, operating aspects connected' with the operation are also significant. Thus, fault operations and consequent unintended resettings of parameters must be avoided, particularly in the cse of largely untrained personnel, but operation nevertheless must be simple and, as already explained, able to be performed after longer intervals of time without resort to tables, manuals or other such aids. The known parametering methods do not to full justice to these subjective requirements.

It is thus the object of the present invention to provide a parametering method which is suitahle for a digital voltage regulator can be easily performed) to a large extent excludes faulty operations, has good operating convenience and permits, for the operator, simple access to the individual parameters in respect of indication of existing set values and also in respect of indication of directional change by new parametering.

According to a first aspect of the present invention there is provided a method of parametering a digital voltage regulator with digital display means fir displaying instantaneous voltage values of 20 the regulator in a non-parametering mode thereof and set values of different parameters of voltage regulation by the regulator in a parametering rode thereof and a plurality of function keys respectively associated with the parameters, the method comprising the steps of selecting a desired parameter for value setting in the 4parametering mode by single or multiple depression of the function key associated with that parameter, the parametering mode being maintained for as long as the key is kept depressed, causing an initial set value of the selected parameter to be displayed by the display means, selectably incrementing or decrementing the set value of the selected parameter by trend actuation of pulse generating means operable in the parametering mode to read out values from fixed storage means, the incrementation or decrementation being continued until a desired final value is attained, causing each incremented or decremented set value to be displayed by the display means and filed in non-volatile storage means, and effecting storage of each attained final value on return of the regulator to the non-parametering mode by release of the depressed key.

In a development of the method, the sum of all instantaneous set values is computed and filed in the non-volatile storage means after each changing of a set value, subsequently the filed sum is compared with the sum of the actual set values of the parameters, and if the compared values do not agree, a fault report is activated and the delivery of control pulses by the regulator is inhibited 20 until the sum of the compared values agrees again after new parametering of all set values, after which the fault report is 0 deactivated.

According to a second aspect of the invention there is provided a digital voltage regulator comprising a plurality of function keys respectively associated with different parameters of voltage regulation by the regulator and each actuable by single or I I- 5. multiple depression to select the associated parameter for value setting in a parametering mode of the regulator, the parametering mode being maintained for as long as an actuated key is kept depressed, digital display means operable to display instantaneous voltage values of the regulator in a non-parametering mode of the regulator and to display set values of s-'ected parameters in the parametering mode, pulse generating means operable in the parametering mode to selectably increment or decrement the set value of a selected parameter by reading out values from fixed storage means until a desired final value is attained, and non-volatile storage means effective in the parametering mode to file incremented or decremented set values and store each attained final value on return of the regulator to the non-parametering mode by release of the respective depressed key.

Preferably, the regulator further comprises means for calculating the sum of all set parameter values and causing the sum to be filed in the non-volatile storage means, means for recalculating the sum and comparing the filed and recalculated sums prior to parametering of the regulator, and means for causing a 20 fault report to be issued and a regulating operation by the regulator to be inhibited in the case of non-agreement of the compared sums and the fault report and inhibition of said operation to be cancelled when all parameter values have been reset and the compared sums are in agreement.

In the case of a method exemplifying and regulator embodying the invention there is the advantage that an unintentional change of ____1__1_1_1_1_111__ICqAI_ -6 a parameter set value is virtually excluded by the necessary "twohap operation for parametering resetting, i.e. the simultaneous dep_(sion of the respective function key and actuation of the pulse generating means. At the same time it is ensured, through the automatic storage of the finally set value on release of the depressed function key, that this storage cannot be forgotten by mistake. Consequently, a high protection against faulty operation is provided. A further advantage is that a direct, undelayed checking and, if appropriate, correction of each set parameter is possible without the necessity of separate switching-over to the actual parametering operation. Finally, a substantial advantage is that due to the specific association of each set parameter with a °:eo key, the parametering of the entire regulator is very simple and, in particular, possible without code lists or other aids. In the afore-mentioned development of the method, it is possible to check the stored parameter values so that any value which has possibly become falsified due to electric, electromagnetic or electrostatic oo disturbance in the non-volatile storage device is recognised and reported. At the same time, the performance of a regulating 20 operation, such as delivery of control pulses to a motor drive, is blocked until the checking of the set values and, if required, their correction. Faulty regulating behaviour due to falsified parameter values thus cannot lead to faulty switching of a transformer controlled by the regulator.

Examples of the method and embodiments of the regulator of the present invention will be more particularly described with reference to the accompanying drawings, in which: -7- Fig. 1 is a flow chart showing the steps of a first method exemplifying the invention; Fig. 2 is a flow chart showing the steps of a second method exempliFying the invention; Fig. 3 is a schematic block diagram of a voltage regulator embodying the invention, for the control of a transformer with a tap selector switch; and Fig. 4 is a front view of a control and operating panel of such a voltage regulator.

Referring now to the drawings, there is shown in Fig. 1 the steps of a first method for the parametering of a digital voltage regulator, which includes inter alia a digital display and a plurality of function keys. In a normal state (non-parametering mode), i.e. when no parametering is or shall be undertaken, the digital display constantly indicates the instantaneous measuired voltage value, i.e. the actual value of the voltage. The function .keys are allocated to different parameters, which can be indicated at the digital display in a parametering mode of the regulator, and reset in value in case of need. The parameter value change itself 20 is effected by a value incrementing and decrementing device, preferably a scroll wheel.

The method itself takes place in the following manner, as indicated by Fig. 1: 1. Rest state: the actual voltage value is indicated.

2. Parameter selection: the appropriate parameter is selected iy depression of the associated one of the function keys, the respective function keys thus being activated.

ss 8- 3. The parameter fixedly associated with the depressed function key is recognised and indicated at the digital display as long as the key remains depressed.

4. At the same time, a direction-dependent pulse generator is activated by the depression of the key and by keeping the key depressed.

The respective next higher or next lower set value of the selected parameter is read out from the tabular storage device by trend actuation of the pulse generator, i.e. actuation in the direction "higher" or "lower" or in the direction "more" or "less", and filed in a non-volatile store, a NOVRAN, a S•battery-floated RAM or perhaps an EEPROM.

6. This operation is repeated as often as desired by repeated trend actuation of the generator until the selected parameter 15 has the desired valca.

7. The respective function key is released when the desired value is reached; the digital display again indicates the measured voltage value, the pulse generator and thereby the increment S transmitter are deactivated, and the new parameter value is 20 stored.

8. Through depression of a different function key, the indication of another paramneter can be effected and through actuation of the increment transmitter, with the function key kept depressed at the same time, resetting of the parameter value can be undertaken in the same manner. Thus, the method steps 1 to 7 are repeated.

I_ 9 Fig. 2 is a flow chart of a second method exemplifying the invention. In this method it is checked before the actual parametering whether the content of the non-volatile memory still correctly contains the stored parameter values or possibly has become falsified by influences of one form or another. For this purpose, the parameter values filed in the memory are added and this sum is compared with the sum of the set values. When this comparison results in no agreement, i.e. the content of the nonvolatile memory is judged to be false, a fault report is activated o. 10 and the delivery of a "higher" or "lower" control pulse by the regulator, in the course of its regulating operation is blocked.

The set values must now be checked until the fault is removed. The actual parametering takes place by the same method steps as those of the first method described with reference to Fig. 1. In augmentation of this first method, after a new set value has been filed in the non-volatile memory, the arithmetic sum of the newly filed set values is formed and later serves as the starting point for the checking of the storage content of the non-volatile memory.

S Fig. 3 is a schematic block diagram of a voltage regulator in which the described parametering methods can be performed. As illustrated, appropriate input magnitudes from a transformer to be regulated are fed byway of an analog-to-digital converter to the voltage regulator via a voltage or current transformer. A centra processor unit (CPU) is connected by way of control lines with an optical coupler, an LED driver, a relay driver and an interface driver, and additionally connectedto a display, a keyboard and a scroll wheel. The processor unit includes an interface, a program store and a working store.

~lb--9k-inQII Fig. 4 shows an operating and control panel of such a voltage regulator. The pulse generator has the form of a scroll wheel 1, but other arrangements, for example a bit generator with or keys, are also possible. A digital display 2, in the simplest case a one-line 7-segment LED display, serves for indication of the measured voltage value in the rest or non-parametering state and of the parameter, which has been selected by actuation of one of the function keys 6 to 15, in the activated or parametering state, i.e.

as long as the respective key remains depressed. Further LED displays 3 indicated the respective measurement unit by lighting up.

Further LED displays 4 and 5 indicate the corresponding preliminary signal in the direction "higher" or "lower" i.e. the exceeding of the regulating deviation beyond the set sensitivity. Finally, the already mentioned function keys 6. to 15, which are respectively associated with the selecible parameters, are disposed below the displays and scroll wheel. An LED display is also associated with the key 16.

It is, of course, possible to allocate several parameters to one function key in order to be able to reduce the number of keys.

20 The selection of a particular parameter in such a case is then effected by repeated actuation of the key and with use of a software changover switch. In order to achieve a high operating security, preferably not more than two parameters should be allocated to one function key.

-I 11~ C-- 11, In the illustrated embodiment, the following parameters are associated with the function keys: 6 switching delay 1/switching delay 2 7 sensitivity/trend indication 8 target value 9 low voltage blocking excess voltage detection 11 overload current blocking/nominal current factor 12 Ur(LDC)/voltage raising 13 Ux(LDC)/voltage limitation 14 Actual value in kilovolts 15 Voltage lowering.

After depression of one of the function keys, the desired parameter value or the desired function can be set by the scroll wheel 1. An increase in numerical magnitude is produced through clockwise rotation and a decrease through anticlockwise rotation.

The value indicated on reler-,e of the'function key will be stored

Claims

12- THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:- 1. A method of parametering a digital voltage regulator with digital display means for displaying instantaneous voltage values of the regulator in a non-parametering mode thereof and set values of different paraneters of voltage regulation by the regulator in a parametering mode thereof and a plurality of function keys respectively associated with the parameters, the method comrrvising the steps of selecting a desired parameter for value setting in the parametering mode by single or multiple depression of the function 10 key associated with that parameter, the parametering mode being maintained for as long as the key is kept depressed, causing an initial set value of the selected parameter to be displayed by the display means, selectably incrementing or decrementing the set value of the selected parameter by trend actuation of pulse generating means ooerable in the parametering mode to read out values from rixed storage means,the incrementation or decremen ation being continued until a desired final value is attained, causing each incremented or decremented set value to be displayed by the display means and filed in non-volatile storage means, and effecting storage of each attained final value on return of the regulator to the non- parametering mode by release of the depressed key. 2. A method as claimed in claim 1, further comprising the steps of calculating the sum of all set parameter values and filing the sum in non-volatile storage means, comparing the filed sum with a CIIIC3-C III I--

13- recalculated sum prior to parametering of the regulator, issuing a fault report and inhibiting a regulating operation by the regulator in the case of non-agreement of the compared sums, and cancelling the fault report and the inhibition of said operation when all parameter values have been reset and the compared sums are in agreement. 3 A method as claimed in claim 1 and substantially as hereinbefore described with reference to Fig. 1 of the accompanying drawings. 10 4. A method as claimed in claim 2 and substantially as hereinbefore described with reference to Fig. 2 of the accompanying drawings. A digital voltage regulator comprising a plurality of function S: key -spectively associated with different parameters of voltage regulation by the regulator and each actuable by single or multiple S depression to select the associated parameter for value setting in a parametering mode of the regulator, the parametering mode being maintained for as long as an actuated key is kept depressed, digital display means operable to display instantaneous voltage values of the regulator in a non-parametering mode of the regulator and to display set values of selected parameters in the parametering mode, pulse generating means operable in the parametering mode to selectably increment or decrement the set value of a selected parameter by reading out values from fixed storage means until a 14 desired final value is attained, and non-volatile storage means effective in the parametering mode to file incremented or decremented set values and store each attained final value on return of the regulator to the non-parametering mode by release of the respective depressed key. 6. A regulator as claimed in claim 5, further comprising means for calculating the sum of all set parameter values and causing the sum to be filed in the non-volatile storage means, means for recalculating the sum and comparing the filed and recalculated sums prior to parametering of the regulator, and means for causing a fault report to be issued and a regulating operation by the regulator to be inhibited in the case of non-agreement of the compared sums and the fault report and inhibition of said operation to be cancelled when all parameter values have been reset and the 15 compared sums are in agreement. 7. A regulator as claimed in claim 5 or claim 6, the pulse generating means comprising a scroll wheel. o 8. A regulator as claimed in any one of claims 5 to 7, wherein the regulator is a control regulator for a transformer with a tap selector switch. 15 9. A digital voltage described with reference drawings. regulator to Figs. substantially as hereinbefore 3 and 4 of the accompanying DATED: 8 OCTOBER 1996 MASCHINENFABRIK REINHAUSEN GMBH By their Patent Attorneys PHILLIPS ORMONDE FITZPATRICK a cc r r r r _UIC__IP~II 16 ABSTRACT A method of parametering a digital voltage regulator, which has a digital display and function keys respectively associated with different parameters, comprises an initial step of depressing a key to select the associated parameter and to place the regulator in parametering mode. The set value of the selected parameter is indicated by the display and can th incremented or decremented by trend actuation of a pulse generator, each amended value being displayed and also filed in a non-volatile memory. On attainment of a desired final value, the key is released, whereupon the funal value is stored and the regulation is returned to a non-parametering mode in which the display indicates regulated voltage values. :0* f 9