Conference Agenda

Increasing environmental concerns and the depletion of petroleum reserves have driven the exploration of renewable and biodegradable insulating fluids for transformers. Conventional mineral oils face disposal challenges, prompting the search for alternatives. Vegetable oil-based transformer fluids meet many of these needs. To address the above issue, in one of our recent studies' it was explored a non-edible vegetable oil based natural esters, an eco-friendly, fire-resistant insulating fluid for transformer application. This study analyses the chemical properties of natural esters using techniques such as Fourier-transform infrared spectroscopy (FT-IR) and gas chromatography with mass spectrometry (GC-MS). It was also examined thermal properties, including thermal conductivity, degradation, and dielectric characteristics. The findings are compared with conventional mineral oil in accordance with national and international standards. Our findings have shown that thermal conductivity decreases with increase in temperatures from 25 to 100 °C for the specific type of natural ester studied. The electrical properties meets the requirement as per IEC standards and proven as an excellent alternative to mineral oils. Natural esters provide numerous benefits: they are abundant, cost-effective, environmentally sustainable, biodegradable, renewable, and do not compete with food industry. Adopting these type of natural esters can lead to a greener future in transformer applications.

One of the major concerns in high-voltage power semiconductor modules is the high electric field stress at the edge of the metallization, where the substrate, encapsulation material, and electrode meet; commonly referred to as the triple junction. If this stress is not controlled, partial discharge may occur, eventually leading to insulation failure. To mitigate this issue, electric field grading techniques, such as the use of permittivity-graded materials in encapsulation, have been investigated. However, the optimal distribution of permittivity remains unclear. This study explores the effective distribution of relative permittivity (𝜀r) in permittivity-graded materials for reducing electric field stress at the triple junction. By comparing the stress-reducing effects of four different types of permittivity distributions, the study aims to identify and discuss the most effective approach.

Modern insulation systems for Hydro Generator Stators use mica-based insulations that are made with either a Vacuum Pressure Impregnation system or a system where resin is preloaded into the mica tapes using a Resin Rich insulation. Traditionally, these systems are based on binding the mica layers together with epoxy that is based on petroleum.

With advances in bio-based materials, there are now sustainable versions of epoxies that are available. Recent work has shown that some of the epoxies that are commonly used in our industry are now available in sustainable form.

Within Andritz, there is a CEO driven initiative to improve our ESG (Environmental, Social, and Governance) performance. Andritz recently has driven work such as removal of chemicals that have Carcinogenic, Mutagenic and Reproductive risks for workers and have invested heavily in businesses and technologies to improve environmental impacts for our customers. In our Hydro Power business more recently, we have teamed up with Isovolta to explore