The technical developement of SMIT Transformers
10Pages

F i r st in Holland built transformer 40 k.V.A. 1050/120V/, delivered to Dutch R ailway together with a g enerator. Source: Anniversary book Smit Slikkerveer >

project of 1886, Smit also had a special bond with Nijmegen, despite it being a city very distant from Slikkeveer, both from a geographical and a cultural point of view. Operations in Nijmegen were started in 1913 with a workforce of approximately 50 employees. The provincial electric companies used an HV network based on 10kV, and in the smaller towns lower voltages of 3.5kV and 6kV were utilised. However, there existed no national standard voltage levels. In the first year the largest capacity transformer manufactured was rated at 1250kVA, with an average capacity of about 30kVA. During...

The Nolen Era, 1916-1955 Prof. Dr. Ir. Henry George Nolen must be regarded as the forefather of transformer technology in Smit Transformers. During his employment, transformer HV ratings increased from 10kV to 220kV and the power ratings increased from 1.25MVA to 200MVA. In 1925 he was appointed Technical Manager of Smit Transformers and he obtained his doctorate with distinction, with a thesis based on Transformer FieldsӔ with Professor Feldman, whom he succeeded in 1937 as Professor. He remained attached to Smit Transformers as Technical Manager until his retirement in 1955, and even...

windings were then lifted on site into the tank, finished and dried, and the final assembly of the transformer took place on site. In 1948, on the occasion of the firm's 35th anniversary, Professor Nolen wrote about this tour de force: I learned a hard lesson then, namely that it is absolutely necessary to always have the building, means of transport, dryers and test devices needed for new objects before they are sold. This has become our guiding principleӔ. Wise words indeed. By 1921 Smit Transformers already had test equipment which was modern for those days and which was already prepared...

followed in 1935 with the use of 150kV rated transformers in the Province of Limburg, though with a relatively small capacity of 6000kVA.The electrification of the railway network at 1500V DC voltage was developing successfully in 1937. The requirements of the transformers were high. Complex Yyd connected designs with 7.5 degree swing windings and extremely small tolerances for the short-circuit voltage were required, for use in connection with the mercury-arc rectifiers. The original capacity amounted to 1200kVA and increased to 2200 kVA in later years. In 1939, the cities of Rotterdam and...

During this period, basic designs were made which could be easily adjusted to the customer's specification. There was also a large amount of technical and project- based consultation with customers occurring. Although it was not yet defined as such then, a co-engineering culture was developing, which paid off in the next period in which more complex orders were obtained. However, market demand resulted in few memorable projects during this period. In 1955, Professor Nolen went into a well-deserved retirement, which marked the end of this era. The New Era 1955-Present The key technical...

19601965: The quality of the transformer oil improved greatly (higher breakdown voltage, higher degradation temperature and less ageing) as a result of which higher field strengths could be incorporated into the transformer designs. From 1995, it became more common to add inhibitors to the oil in order to provide it with even better properties. 1965֖1975: Complex calculations by hand gave gradually way to various types of calculators. At first a kind of Hollerith-like cards were used, which were processed in Delft; with the calculation result returned by post to Nijmegen. Between 1975 and...

During 1968-1970, the SEP (Association of Electricity-Generating Undertakings) started with the construction of a national interconnected network within the Netherlands at the 380kV level. Smit Transformers delivered the first single-phase units rated at 150 MVA, 380/ winding hotspot was situated, and the difference between the hotspot temperature and that of the average winding temperature could be easily seen. This resulted in designs featuring reduced winding hotspot temperatures and a corresponding extended life expectancy. √ 3//150/ √ 3//50kV, thus forming a three-phase bank of 450...

measurements of noise levels were carried out in the customer's presence, with the result that the noise requirements were completely satisfied. In 1987, one of our most loyal U.S. customers, NYPA, a firm we have supplied since 1978, granted us the order for the so far largest U.S. generator transformer, 607MVA 345/20.3 kV, 60 Hz. For the transformer factory acceptance tests, Smit Transformers have their own generators, which are capable of generating at either 50Hz or 60 Hz by means of a gearbox located between the motor and generator. In 1989, the designers faced a real challenge. UNA...

project was completed to the full satisfaction of the customer. At the time these were the largest PSTҒs in the world. Further information about Willem Smit: www.willemsmithistorie.nl 10 >