– From Norway’s First Voltage regulating Distribution Transformer (VRDT) to Award-Winning Voltage Regulators.
At Snefjellåga in Nordland, nearly 10 years ago, a VRDT with an automatic on-load tap changer (OLTC) was commissioned. This «automatic voltage regulator» was the first of its kind in the Nordic region, and Linja AS engineer Eivind Parelius was the driving force behind the project.
The year was 2016, and the VRDT was considered expensive, while building a new grid would cost «only» around NOK 700,000 per kilometer. Nevertheless, Linja saw the potential of this type of solution from both a cost and grid operation perspective. “Even though the investment cost for this first transformer is high, we expect prices to decrease”, said Parelius at the time.
The transformer was supplied by Magtech AS and Norsk Transformator AS, with the OLTC provided by Maschinenfabrik Reinhausen (MR). This marked the beginning of what would become an exciting collaboration between Regensburg and Steinkjer.
Nearly a decade of experience later, Magtech receives the Innovation of the Year Award at the Smart Grid Conference in Trondheim, hosted by The Norwegian Smartgrid Centre, for its Medium Voltage Regulator, which increases capacity and postpones grid investments in the medium voltage network. Together with MR, Magtech has developed a 3-in-1 solution where the OLTC, originally designed for distribution transformers, has been placed in a 22/22kV autotransformer. Additionally, a tertiary delta winding has been designed to function both as a voltage measurement transformer and as a low-voltage power supply for the substation. This innovation halves the cost of typical Medium Voltage Regulator installations and has brought Magtech international recognition.
«Magtech has the longest experience and most installations in the Nordics. Looking at past pilot projects, we see you helping your customers solve their problems,» says Franco Pizzutto, Business Development Manager at MR. This experience benefits customers now that the price of OLTCs has dropped, while the cost of traditional grid reinforcement has increased significantly. Pizzutto continues, «The price level for each development step of our OLTCs has seen at least a 25% decrease.» Even though the raw material prices for transformers have risen over the years, the price for the complete VRDT has actually gone down.
At a time when grid capacity needs to increase dramatically, and deferred maintenance is a pressing issue for most DSO’s, voltage regulation will only become more critical. The technology is well-proven, and in Europe, we are already witnessing a shift:
«Several DSOs are currently ordering around 80-100%(!) of their distribution transformers as VRDTs with our ECOTAP VPD,» says Pizzutto.
