EP0039817B1 - Méthode de réglage de la tension d'un électrofiltre placé dans une installation - Google Patents

Méthode de réglage de la tension d'un électrofiltre placé dans une installation Download PDF

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Publication number
EP0039817B1
EP0039817B1 EP81103149A EP81103149A EP0039817B1 EP 0039817 B1 EP0039817 B1 EP 0039817B1 EP 81103149 A EP81103149 A EP 81103149A EP 81103149 A EP81103149 A EP 81103149A EP 0039817 B1 EP0039817 B1 EP 0039817B1
Authority
EP
European Patent Office
Prior art keywords
voltage
filter
electrofilter
parameter values
breakdown
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.)
Expired
Application number
EP81103149A
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German (de)
English (en)
Other versions
EP0039817A1 (fr
Inventor
Helmut Dipl.-Ing. Herklotz
Günter Mehler
Franz Dipl.-Ing. Neulinger
Helmut Dipl.-Ing. Schummer
Horst Dr. Dipl.-Ing. Daar
Walter Dipl.-Ing. Schmidt
Heinrich Winkler
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.)
GEA Group AG
Siemens AG
Original Assignee
Metallgesellschaft AG
Siemens AG
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 Metallgesellschaft AG, Siemens AG filed Critical Metallgesellschaft AG
Priority to AT81103149T priority Critical patent/ATE8849T1/de
Publication of EP0039817A1 publication Critical patent/EP0039817A1/fr
Application granted granted Critical
Publication of EP0039817B1 publication Critical patent/EP0039817B1/fr
Expired legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C3/00—Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
    • B03C3/34—Constructional details or accessories or operation thereof
    • B03C3/66—Applications of electricity supply techniques
    • B03C3/68—Control systems therefor
    • 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
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S323/00—Electricity: power supply or regulation systems
    • Y10S323/903—Precipitators

Definitions

  • the invention relates to a method for regulating the voltage of an electrostatic filter used in a system with a computer, in which parameter values used for the regulation are taken into account depending on the process in such a way that in the event of a breakdown, the filter voltage is reduced by a predetermined value and then with a predetermined temporal voltage gradient until the breakthrough is increased again.
  • predetermined parameter values such as, for. B. current, voltage or rollover frequency, compared with predetermined setpoints and derived control commands.
  • the control works so that after reaching the operating voltage, the filter voltage of the respective breakdown voltage is adjusted by scanning the breakdown limit. After each breakthrough, the power supply to the filter is immediately blocked and, after an deionization time has elapsed, it is rapidly ramped up to a voltage which is a small amount lower than the voltage before the breakthrough. From this value, the control voltage and thus the filter voltage is then slowly increased again at an adjustable speed until a new breakdown, whereupon the measures described above are repeated.
  • the breakdown frequency is dependent on the amount of voltage drop after each breakdown and the voltage gradient over time.
  • the nominal current of the system is also of interest. If the dust resistance is low, the nominal current limit of the system can be reached earlier than the breakthrough limit. Even in such a case, the automatic control system must limit the current, and the current limitation should also be adjustable.
  • the object of the present invention is to design the method of the type mentioned in such a way that the operating point of the filter is adapted as optimally as possible to the changing operating states of the overall system.
  • the filter operation can be adapted to the changing process conditions.
  • the electrostatic filter system connected downstream of a converter may serve as an example. It can be seen that the dust accumulation will also differ during the various operating states of the converter system.
  • the operating point of the electrostatic precipitator or the electrostatic precipitator system is also set in such a way that energy is not wasted unnecessarily. Further examples of this are given at the end of the description.
  • the parameter values can also be advantageously changed by a higher-level master computer that is informed about the respective status of the overall process and can accordingly calculate optimization strategies.
  • the high-voltage rectifier 4 supplying the direct voltage for the electrostatic filter 1 is fed from an alternating-voltage network N via a thyristor actuator 2 and a high-voltage transformer 3.
  • the control voltage U st for the tax rate 5 of the thyristor actuator 2 is from a z. B. digital controller 6, the actual value side of the primary current Ip, the filter current I F and the filter voltage U F proportional signals are supplied.
  • the controller 6 is also supplied with a signal D which indicates a breakdown.
  • a high-voltage breakdown detection is described, for example, in the above-mentioned article from Siemens magazine 1971.
  • the voltage is reduced by a predetermined value.
  • This value can be selected as a percentage value k of the filter voltage present in each case; ie the filter voltage drop is where k z. B. can fluctuate between 1 and 5%.
  • a number of these parameter values k are written into a memory 61 assigned to the controller 6 when the control is started up.
  • the voltage is then increased again with a predetermined time voltage gradient a until the next breakdown.
  • a number of different gradients are stored in a further memory 62 when the control is started up.
  • the control unit receives signals dependent on the process, such as. B. represented by line 11.
  • process-dependent signals z. B. serve signal signals about the operating state of the entire system, z. B. blowing operation with a converter or information about gas velocity and gas humidity.
  • the process-dependent signals can also be derived from a dust loading measuring device 8 provided in the electrostatic filter 1.
  • the control unit 7 can be constructed relatively simply, for. B. in the form of a decoder, it only needs to correspond to a specific request and report of operating states on line 11, a corresponding switch position of the switch 64.
  • FIG. 2 which represents an idealized course of the filter DC voltage
  • a filter breakdown D occurs at time t o .
  • the filter is temporarily blocked and the filter voltage is then set to a new value reduced by the amount JU, if necessary after a certain deionization time and waiting time, the reduction amount ⁇ U being proportional to the filter voltage, ie
  • the voltage with the predetermined gradient ⁇ is then increased, if necessary after a certain waiting time, until the breakdown D occurs again at time t 1 , whereupon the game is repeated again.
  • Fig. 3 shows the structure of the digital controller 6 as a microcomputer system 9.
  • the microcomputer system consists essentially of two microprocessors 91 and 92, of which the microprocessor 91 is used for the actual control and the microprocessor 92, which works as a slave processor, the measured value processing and punch detection.
  • An input / output 95 is also connected to the bus 96, to which the two microprocessors 91 and 92 are connected, via which the microcomputer system takes the measured values from the electrostatic filter system and outputs the control voltage U st to the actuator 5.
  • a semiconductor memory 93 for the system program and the data is also connected to the same bus 96. Communication with a higher-level master computer is possible via a coupling module 94, which is also provided, as indicated by line 99.
  • the individual parameter values are entered into the microcomputer system, which is constructed in the same way for all filter systems, via a supply device 97 with the aid of a programming device 98. In this way, the same control can be individually adapted to the different filters and filter zones.
  • each of the electrostatic filters 1-111 is a Assigned control serving microcomputer system 9, which communicates via a bus 99 with a higher-level control computer 10. With this master computer, optimization strategies can then be calculated and, depending on the dust loading detected by a measuring device 8 and / or the operating states of the system supplied via line 11, those parameter values are activated in the controls 9 which result in an optimal overall efficiency of the system; e.g. B. it is conceivable that the filters 1 and 2 are reduced in their performance in a time of low dust and only the filter 3 is operated at full power.
  • process signals temperature, dust fraction, gas composition (CO, H 2 etc.), raw gas dust quantity, clean gas dust content, pressure, gas velocity, dust resistance and gas humidity; for a power plant: load status, load change gradient, type of coal burned (sulfur content) and for waste incineration: type of waste to be burned (composition), type of additional combustion (oil, natural gas, coal).
  • the parameters affected by parameters include: filter current, filter voltage, permitted undervoltage limit, permitted number of breakdowns, gradient of the scan, level of filter voltage reduction during the knocking measures, recording of the filter characteristics allowed (yes / no), pause time of the knocking, duration of the knocking, frequency knocking measures, quantity of conditioning additives (e.g. S0 3 , H 2 0), type of reaction to a breakdown (e.g. length of deionization time, ramp-up time, voltage reduction), length of search periods (for optimization strategies) and length of time keeping the filter voltage constant (until the breakdown limit is sampled again).

Landscapes

  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Electrostatic Separation (AREA)
  • Elimination Of Static Electricity (AREA)
  • Superconductor Devices And Manufacturing Methods Thereof (AREA)
  • Inorganic Insulating Materials (AREA)
  • Control Of Electrical Variables (AREA)
  • Feedback Control In General (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)

Claims (4)

1. Procédé de réglage de la tension d'un élec- trofiltre (1) mis en oeuvre dans une installation, à l'aide d'un ordinateur (6), et selon lequel des valeurs de paramètres servant au réglage sont prises en compte en fonction du processus de telle sorte que dans le cas d'une décharge, la tension (UF) du filtre est réduite d'une valeur prédéterminée (AU) et est ensuite accrue avec un gradient prédéterminé de tension dans le temps (α) jusqu'à une nouvelle décharge (D), caractérisé par les moyens suivants:
a) lors de la mise en service du filtre (1), une série de valeurs de paramètres sont introduites dans des mémoires à semiconducteurs (61-63) pour chacun des paramètres: diminution de la tension (ΔU), gradient de tension (α) et courant nominal (JFN), et
b) les valeurs, servant au réglage, des différents paramètres (ΔU, α, JFN) sont rendues actives en fonction du processus.
2. Procédé suivant la revendication 1, caractérisé par le fait que lors de la mise en service, différentes valeurs pour d'autres paramètres sont en supplément mémorisées et rendues actives pour le réglage en fonction du processus.
3. procédé selon la revendication 1, caractérisé par le fait que les valeurs des paramètres sont rendues actives en fonction des signaux d'un appareil (8) de mesure de la charge en poussière.
4. Procédé suivant les revendications 1 et 2, caractérisé par le fait que les valeurs des paramètres sont rendues actives par des instructions d'un calculateur pilote (10) de rang supérieur que est prévu pour une multiplicité d'électrofiltres
EP81103149A 1980-05-08 1981-04-27 Méthode de réglage de la tension d'un électrofiltre placé dans une installation Expired EP0039817B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT81103149T ATE8849T1 (de) 1980-05-08 1981-04-27 Verfahren zum regeln der spannung eines in einer anlage eingesetzten elektrofilters.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19803017685 DE3017685A1 (de) 1980-05-08 1980-05-08 Verfahren zum regeln der spannung eines in einer anlage eingesetzten elektrofilters
DE3017685 1980-05-08

Publications (2)

Publication Number Publication Date
EP0039817A1 EP0039817A1 (fr) 1981-11-18
EP0039817B1 true EP0039817B1 (fr) 1984-08-08

Family

ID=6101937

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81103149A Expired EP0039817B1 (fr) 1980-05-08 1981-04-27 Méthode de réglage de la tension d'un électrofiltre placé dans une installation

Country Status (7)

Country Link
US (1) US4432061A (fr)
EP (1) EP0039817B1 (fr)
JP (1) JPS574245A (fr)
AT (1) ATE8849T1 (fr)
AU (1) AU534688B2 (fr)
DE (2) DE3017685A1 (fr)
ZA (1) ZA813032B (fr)

Families Citing this family (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3048979C2 (de) * 1980-12-24 1986-09-04 Thyssen Industrie Ag, 4300 Essen Verfahren zum Betrieb eines Elektroabscheiders für die Gasentstaubung und Vorrichtung dazu
SE8104574L (sv) * 1981-07-28 1983-01-29 Svenska Flaektfabriken Ab Styranordning for en elektrostatisk stoftavskiljare
DK355382A (da) * 1982-08-09 1984-02-10 Smidth & Co As F L Fremgangsmaade til styring af et impulsdrevet elektrofilter til minimal effektoptagelse ved en given rensningsgrad
DE3233249C2 (de) * 1982-09-08 1986-10-02 Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt Verfahren zum Steuern eines Elektroabscheiders und Steuerungsvorrichtung zur Durchführung des Verfahrens
DE3241060A1 (de) * 1982-11-06 1984-05-10 Buckau-Walther AG, 4048 Grevenbroich Elektrische schaltung fuer einen elektrostatisch arbeitenden staubabscheider
DE3326041A1 (de) * 1983-07-20 1985-02-07 Siemens AG, 1000 Berlin und 8000 München Regeleinrichtung fuer ein elektrofilter
US4605424A (en) * 1984-06-28 1986-08-12 Johnston David F Method and apparatus for controlling power to an electronic precipitator
GB8431293D0 (en) * 1984-12-12 1985-01-23 Smidth & Co As F L Controlling pulse frequency of electrostatic precipitator
US4747061A (en) * 1986-03-17 1988-05-24 Westinghouse Electric Corp. Automatic transfer switch for a wide range of source voltage
DK552186A (da) * 1986-11-19 1988-05-20 Smidth & Co As F L Fremgangsmaade og apparat til detektering af tilbagestraaling i et elektrofilter med almindelig eller intermitterende jaevnspaendingsforsyning
DK171319B1 (da) * 1987-08-06 1996-09-02 Smidth & Co As F L Fremgangsmåde til styring af en roterovn under opstart
US4811197A (en) * 1987-09-02 1989-03-07 Environmental Elements Corp. Electrostatic dust collector system
JPH05505137A (ja) * 1990-04-04 1993-08-05 シーメンス アクチエンゲゼルシヤフト 電気集塵装置の電力供給装置に対する調節方法
DE4142501C1 (fr) * 1991-12-21 1992-12-10 Metallgesellschaft Ag, 6000 Frankfurt, De
DE4222069A1 (de) * 1992-07-04 1994-01-05 Rothemuehle Brandt Kritzler Verfahren zum Betrieb eines Elektrofilters sowie Elektrofilter zur Ausübung des Verfahrens
US5378978A (en) * 1993-04-02 1995-01-03 Belco Technologies Corp. System for controlling an electrostatic precipitator using digital signal processing
SE506246C2 (sv) * 1996-03-28 1997-11-24 Flaekt Ab Förfarande för styrning av en elektrostatisk stoftavskiljare
DE10050188C1 (de) * 2000-10-09 2002-01-24 Siemens Ag Verfahren zum Betrieb eines Elektrofilters
DE10214185A1 (de) * 2002-03-28 2003-10-16 Siemens Ag PC-Anordnung für Visualisierungs-, Diagnose- und Expertensysteme zur Überwachung und Steuerung bzw. Regelung von Hochspannungsversorgungseinheiten von Elektrofiltern
EP1872858A3 (fr) * 2006-06-29 2011-05-11 Siemens Aktiengesellschaft Procédé d'optimisation d'un filtre électrostatique multi-zones
US7488375B1 (en) * 2007-10-23 2009-02-10 Inventec Corporation Fan cooling system
EP2397227A1 (fr) * 2010-06-18 2011-12-21 Alstom Technology Ltd Procédé pour contrôler la distorsion de ligne dans un système d'alimentations électriques de dépoussiéreurs électriques
EP2873464A1 (fr) * 2013-11-13 2015-05-20 Siemens VAI Metals Technologies GmbH Filtration d'un gaz d'échappement, présentant des particules solides, d'une installation technique sidérurgique

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US3507096A (en) * 1967-03-07 1970-04-21 Cottrell Res Inc Method and apparatus for automatic voltage control of electrostatic precipitators
DE1923952C3 (de) * 1969-05-10 1980-04-30 Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt Regelvorrichtung für einen Elektroabscheider zum elektrostatischen Abscheiden von Aerosolen, insbesondere für die Abgasentstaubung
US3622839A (en) * 1970-01-19 1971-11-23 Robicon Corp Control system for electrostatic precipitator power supply
US3745749A (en) * 1971-07-12 1973-07-17 Envirotech Corp Circuits for controlling the power supplied to an electrical precipitator
GB1424346A (en) * 1972-11-16 1976-02-11 Lodge Cottrell Ltd Automatic voltage controller
JPS5344068B2 (fr) * 1972-11-25 1978-11-25
DE2317256C3 (de) * 1973-04-06 1983-11-24 Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt Steuer- und Regeleinrichtung für eine Anlage zum Abscheiden von Aerosolen mit einem Elektroabscheider
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Also Published As

Publication number Publication date
AU7024481A (en) 1981-11-12
DE3017685A1 (de) 1981-11-12
DE3165352D1 (en) 1984-09-13
JPS574245A (en) 1982-01-09
ZA813032B (en) 1982-05-26
ATE8849T1 (de) 1984-08-15
AU534688B2 (en) 1984-02-09
EP0039817A1 (fr) 1981-11-18
US4432061A (en) 1984-02-14

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