DE1563157B2

DE1563157B2 - CIRCUIT ARRANGEMENT WITH AN INPUT FILTER ARRANGED BETWEEN A DC SOURCE AND AN INVERTER

Info

Publication number: DE1563157B2
Application number: DE19661563157
Authority: DE
Inventors: Hans 6000 Frankfurt. H02p 13-30 Schuchardt
Original assignee: Voigt & Haeffner Gmbh, 6000 Frankfurt
Priority date: 1966-10-20
Filing date: 1966-10-20
Publication date: 1972-02-17
Also published as: DE1563157A1

Description

28 000 }iF, ist die Kapazität des Kondensators 3 gegenüber der Kapazität des Ladekondensators 6 vernachlässigbar klein. Der Widerstand 6', mit einem Wert von 0,66 Ohm, wird beim stationären Betrieb des Wechselrichters 7 durch Kontakte 8 eines Zeit- S relais 9 überbrückt, welches eine Laufzeit von beispielsweise 0,3 Sekunden vom Schließen des Schalters 2 bis zum Schließen der Kontakte 8 besitzt. Wechselrichter und Eingangsfilter sind an eine Gleichstromquelle 10, die eine Batterie sein kann, zusammen mit einem oder mehreren Verbrauchern 11 angeschlossen. Der Verbraucher 11 kann beispielsweise eine Fernsprechanlage sein. F i g. 1 zeigt die Anlage unmittelbar nach dem Einschalten, d. h. nach dem Schließen des Schalters 2, aber vor dem Schließen der Kontakte 8. Während dieser Zeit treten die eingangs geschilderten Nachteile auf, indem nämlich infolge der hohen Kapazität des Kondensators 6 über den Widerstand 6' und die Drosselspule 4 ein hoher Strom von beispielsweise maximal 280 A fließt. Die Zeitkonstante beträgt in diesem Falle 26 Millisekunden, die für ein optimales Anlaufen des Wechselrichters 7 erforderlich sind. Nach dem Schließen der Kontakte 8, d. h. nach 0,3 Sekunden, liegt die mittlere Stromaufnahme bei 57 A. Die Einschalt-Stromspitze war somit rund fünfmal so hoch.28 000} iF, is the capacitance of capacitor 3 negligibly small compared to the capacitance of the charging capacitor 6. Resistance 6 ', with a A value of 0.66 ohms is determined by the contacts 8 of a time S during steady-state operation of the inverter 7 Relay 9 bridged, which has a running time of, for example, 0.3 seconds from closing the switch 2 until the contacts 8 close. Inverter and input filter are connected to one Direct current source 10, which can be a battery, together with one or more consumers 11 connected. The consumer 11 can for example be a telephone system. F i g. 1 shows the system immediately after being switched on, d. H. after closing switch 2, but before Closing the contacts 8. During this time, the disadvantages outlined above occur, namely due to the high capacitance of the capacitor 6 via the resistor 6 'and the choke coil 4 high current of, for example, a maximum of 280 A flows. The time constant in this case is 26 milliseconds, which are necessary for the inverter 7 to start up optimally. After closing of contacts 8, d. H. after 0.3 seconds, the average current consumption is 57 A. The inrush current peak was thus around five times as high.

F i g. 2 zeigt die erfindungsgemäße Schaltung, wobei die Bezugszeichen aus F i g. 1 übernommen sind. Bei gleichen Bezugszeichen besitzen die entsprechenden Bauteile im Ausführungsbeispiel auch die gleichen technischen Daten.F i g. 2 shows the circuit according to the invention, the reference symbols from FIG. 1 are adopted. With the same reference numerals, the corresponding components in the exemplary embodiment also have the same ones technical data.

Das Zeitglied aus Fig. 1, bestehend aus dem Kondensator 6 mit einer Kapazität von 28 000 ,uF und dem Widerstand 6', ist in F i g. 2 in zwei Teilzeitglieder 12 und 13 aufgeteilt. Das Teilzeitglied 13 besteht aus dem Kondensator 15 und dem Widerstand 15'. Der Kondensator 15 liegt parallel am Eingang des Wechselrichters 7 und hat eine Kapazität von 10 000 nF. Der Widerstand 15' hat einen Wert von 1,85 Ohm. Mit diesem Wert ergibt sich für das Ansteigen der Spannung eine Zeitkonstante von 26 Millisekunden, entsprechend der Anordnung von Fig. 1.The timing element from Fig. 1, consisting of the capacitor 6 with a capacitance of 28,000 µF and the resistance 6 'is shown in FIG. 2 in two part-time members 12 and 13 split. The part-time element 13 consists of the capacitor 15 and the resistor 15 '. The capacitor 15 is parallel to the input of the inverter 7 and has a capacity of 10,000 nF. The resistor 15 'has a value of 1.85 ohms. This value results in an increase the voltage has a time constant of 26 milliseconds, corresponding to the arrangement of FIG. 1.

Das Zeitglied 12 besteht aus dem Kondensator 14 mit einer Kapazität von 18 000 μΈ und dem Widerstand 14' mit einem Wert von 4,5 Ohm.The timing element 12 consists of the capacitor 14 with a capacity of 18,000 μΈ and the resistor 14 'with a value of 4.5 ohms.

Die Summe der Kapazitäten der Kondensatoren 14 und 15 beider Zeitglieder ist gleich der Kapazität des Kondensators 6 entsprechend der Anordnung von Fig. 1.The sum of the capacities of the capacitors 14 and 15 of both timing elements is equal to the capacitance of the Capacitor 6 corresponding to the arrangement of FIG. 1.

Der Wert des Widerstandes 14' bewirkt die Aufladung des Kondensators 14 mit einer Zeitkonstanten von etwa 80 Millisekunden. Diese Zeitkonstaiite ist so gewählt, daß der Kondensator 14 nach Ablauf des Zeitrelais 9 und dem Schließen der Kontakte 8 gerade mit Sicherheit voll aufgeladen ist.The value of the resistor 14 'causes the capacitor 14 to be charged with a time constant of about 80 milliseconds. This Zeitkonstaiite is chosen so that the capacitor 14 after expiration of the timing relay 9 and the closing of the contacts 8 is definitely fully charged.

Bei der erfindungsgemäßen Schaltung nach F i g. 2 tritt bei den angegebenen Daten der einzelnen Bauteile eine Einschaltstromspitze von nur 107 A auf. Das sind knapp 40.% der Einschaltstromspitze bei der Schaltung nach Fig. 1. Der aufgenommene Betriebsstrom nach Schließen der Kontakte 8 steigt bei F i g. 2 nur unwesentlich auf 65 A.In the circuit according to the invention according to FIG. 2 occurs with the specified data of the individual components an inrush current peak of only 107 A. That is almost 40% of the inrush current peak at the circuit according to FIG. 1. The operating current consumed after closing the contacts 8 increases at F i g. 2 only insignificantly to 65 A.

Hierzu 1 Blatt Zeichnungen1 sheet of drawings

Claims

1 2 on the other hand, the voltage rise must not be too slow.

1. Circuit arrangement with an intermediate stors for the opposite half-wave is not achieved a direct current source and an inverter 5 can be.

ter arranged input filter with one of it is also known, during the switch-on Series connection of a charging capacitor to put a resistor in the filter circuit, and one only immediately after switching on which is dimensioned in such a way that the voltage on the Ladedes Inverter effective, otherwise short capacitor with a favorable one for the thyristors closed resistance existing timer, io time constant (about 20 to 30 milliseconds with a characterized in that the time-generated frequency of 50 Hz) increases. The size member in two or more part-time members (12,13) capacity of the charging capacitor has despite the resistance significantly different time constants when switching on the inverter is divided. result in a very high charging current, the voltage input

2. Circuit arrangement according to claim 1, that causes 15 breaks in the direct current source. These characterized in that parallel to the charging lead to disturbances in the other connected capacitor (1.5) of the part-time element (13) with the consumers. In addition, backups are twinned Time constant of the inverter (7) see the power source and input filter with regard to lies. a change in the tripping characteristic and a

3. Circuit arrangement according to claim 2, there is a detrimental effect on shortening the service life, characterized by the fact that the smallest time con It would now be obvious to use the resistance in the constant in the order of 20 to 3OMiUi- filter circuit to increase the inrush current Seconds. Reduce. However, this measure would have

4. Circuit arrangement according to claim 1, corresponding extension of the time constant of the characterized in that the time constant of the filter results in that according to the above off part-time element (12) with the largest time settings is not acceptable.

stanten a maximum of one third of the running time of a. It is therefore the object of the invention to provide a

to short-circuit the resistors serving circuitry to create the charging current

Time relay (9) is. while maintaining the favorable for the thyristors

30 Time constant reduced.

The task at hand is thereby achieved with a circuit arrangement of the type mentioned at the beginning

The invention relates to a circuit that the timing element in two or more sub-arrangements with a DC timing element with a significantly different time con source and an inverter arranged constants 35 is divided.

output filter with one of a series connection of a In this way, the current consumption of the FiI charging capacitor and one only stretched immediately after ters over a longer period of time and the . effective when the inverter is switched on, current peak is kept low. Nevertheless it works otherwise short-circuited resistance existing inverter due to the unstretched span timer. Such an arrangement is already known. 40 voltage timing at its input terminals faulty

Due to their intermittent nature, inverters have free.

Power consumption repercussions on the feeding it expedient configurations of the invention power source, in the form of vibrations on the object are that parallel to the loading one occur in a wide frequency band. This is the uncapacitor of the part-time element with the smallest It is pleasant when the inverter also has a 45 time constant connected to the power source that the other consumers are connected to the smallest time constant of the order of 20 carry over the repercussions. Particularly disadvantageous is up to 30 milliseconds and that the time constant is the influence of the inverter if it is the part-time element with the largest time constant the other consumers by electroacoustic connections a maximum of one third of the running time of a short-term, z. B. telephones, acts in which 5 ° close the resistors is serving timing relay. the repercussions are noticeable as continuous disturbing noise do. To avoid this, the device is already explained in more detail with reference to the drawing; it shows the inverters what are known as input filters

been switched, which the current oscillations in F i g. 1 a conventional and

of the inverter's feed line. A 55 F i g. 2 the circuit according to the invention,

such a known filter consists, for example, of FIG. 1 is with 1 a fuse and with 2 the

a charging capacitor, which, in parallel with the source of interference, designates a switch for the filter circuit and the inverter.

so the input of the inverter, switched is net. 3 is a capacitor that works together with a

and one or more LC members. To, especially choke coil 4 is a filter member, in particular for

this is the case with inverters with higher powers, 60 higher frequencies. However, this filter element is intended

sufficient effect of the charging capacitor is not of interest here, since the capacitor 3 is a

enough, this must have a relatively large Ka- very low value, for example 20 μΡ, so

have capacity. that due to the low charging current of the condenser

If, for example, thyristors are used as the switch 3, a special current limiting resistor is used elements of the inverter are used, so it is 65 superfluous. A timing element is denoted by 5, expediently, the voltage at the inverter unit which consists of a charging capacitor 6 of the input gear not to be switched on suddenly, but consists of the filter and a resistor 6 '. At a To let the power-on instant increase. Anderer- capacity of the charging capacitor 6 of z. B.