AT134216B

AT134216B - Method and device for facilitating the starting of mercury vapor rectifiers.

Info

Publication number: AT134216B
Authority: AT
Original assignee: Bbc Brown Boveri & Cie
Priority date: 1931-05-18
Filing date: 1932-05-09
Publication date: 1933-07-25
Also published as: CH163125A

Description

  

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  Verfahren und Einrichtung zum Erleichtern des Anlassens von   Quecksilberdampfgieichrichtern.   



   Es ist bekannt, dass bei Quecksilberdampfgleichrichtern, die im kalten Zustand belastet werden, besonders bei Stosslasten,   Rückzündungen   auftreten. Die Ursache liegt darin, dass der Quecksilberdampfdruck in der Umgebung des Lichtbogens zu niedrig und daher der Lichtbogenabfall von Anode zur Kathode sehr gross und zudem sehr starken Schwankungen unterworfen ist. Diese Schwankungen, die ziemlich hohe Frequenzen haben können (z. B. zwischen 1000 und 10.000), können mit der Transformatorreaktanz   und-kapazität   in Resonanz geraten und hohe   Überspannungen   erzeugen, welche ihrerseits Rückzündungen zur Folge haben.

   Es ist nun bereits vorgeschlagen worden, die Temperatur des Gleichrichters bei kleiner Last oder bei abgestelltem Gleichrichter dadurch auf einer bestimmten Höhe zu halten, dass in den Kühlmantel des Gleichrichters Thermostate eingebaut werden. Diese Anordnung führt jedoch   keine gleichmässige Erwärmung   des Gleichrichters herbei, weil das warme Wasser stets nach oben steigt ; die unteren Partien des Gleichrichters bleiben kalt. Man hat ferner bereits vorgesehlagen, in die Kiihlwasserleitungen des Gleichrichters Heizeinrichtungen einzubauen, um das Kiihlwasser anzuwärmen und diese automatisch bei Inbetriebnahme einzuschalten, bei Erreichen einer bestimmten Temperatur aber abzuschalten.

   Es ist ferner bekannt, zur Formierung des Gleichrichters in das Gefäss eine Heizwieklung einzulegen, um die vorhandene Feuchtigkeit usw. zu beseitigen, die aber bisher nach erfolgter Formierung wieder aus dem Gleichrichter herausgenommen wird. 

**WARNUNG** Ende DESC Feld kannt Anfang CLMS uberlappen**.



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  Method and apparatus for facilitating the tempering of mercury vapor straighteners.



   It is known that reignitions occur in mercury vapor rectifiers which are loaded in a cold state, especially with shock loads. The reason is that the mercury vapor pressure in the vicinity of the arc is too low and therefore the arc drop from the anode to the cathode is very large and also subject to very strong fluctuations. These fluctuations, which can have fairly high frequencies (e.g. between 1000 and 10,000), can resonate with the transformer reactance and capacitance and generate high overvoltages which in turn result in reignitions.

   It has already been proposed to keep the temperature of the rectifier at a certain level when the load is low or when the rectifier is switched off by installing thermostats in the cooling jacket of the rectifier. However, this arrangement does not bring about even heating of the rectifier because the warm water always rises to the top; the lower parts of the rectifier remain cold. It has also already been proposed that heating devices be built into the cooling water lines of the rectifier in order to warm up the cooling water and to switch it on automatically when it is started up, but to switch it off when a certain temperature is reached.

   It is also known to insert a heating element into the vessel in order to form the rectifier in order to remove the existing moisture, etc., which, however, has so far been removed from the rectifier again after formation.

** WARNING ** End of DESC field may overlap beginning of CLMS **.

Claims

According to the invention, this heating element, which was previously only used for formation, is now permanently built into the rectifier and used to facilitate starting the rectifier in the cold state by accelerating the formation of steam. The heating winding is expediently arranged in the vicinity of the bottom of the rectifier housing, because the housing is coolest there due to the constantly flowing cooling water. The power supply to the radiator is vacuum-tight through the cover using a heat-resistant coating for the supply lines inside the housing. The heating function is expediently switched on automatically when the rectifier is started up before the ignition is switched on and switched off after ignition has taken place.

It is easily possible to switch on the heating coil during operation if the self-heating of the rectifier is insufficient to maintain operation, PATENT CLAIM: Method and device for facilitating the starting of mercury vapor rectifiers, characterized in that the heating coil previously only used for forming is permanently installed in the rectifier and used to facilitate starting the rectifier when cold by accelerating the formation of steam. ** WARNING ** End of CLMS field may overlap beginning of DESC **.