Glossary
Energy infrastructure from A to Z
This glossary summarizes key terms relating to transformers and modern energy infrastructure. For each letter of the alphabet, you will find one or more carefully selected terms with detailed explanations, frequently asked questions, and practical guidance.
The content is aligned with the product and application areas of R&S Group: power and distribution transformers, cast-resin transformers, oil-type transformers, BESS solutions, and more.
Do you have further questions or a specific project in mind? Get in touch with us – we look forward to the exchange.
A
Alternating Current
The Foundation of Modern Power Supply
Read more – Alternating CurrentAmorphous Cores
Highly Efficient Core Technology for Modern Transformers
Read more – Amorphous CoresAmpere
The Unit of Electrical Current Explained
Read more – AmpereAnnual Maintenance
Investment in Security of Supply and Service Life
Read more – Annual MaintenanceB
Battery Energy Storage Systems (BESS)
Key Technology for a Flexible Power Grid
Read more – Battery Energy Storage Systems (BESS)Buchholz Relay
Proven Gas Protection for Oil-Type Transformers
Read more – Buchholz RelayC
Cable Termination
Reliable Handover from Cable to Downstream Equipment
Read more – Cable TerminationCast-Resin Transformer
Safe Power Supply Without Oil
Read more – Cast-Resin TransformerCast-Resin Transformer
Powerful, Compact, and Oil-Free
Read more – Cast-Resin TransformerCondition Monitoring
An Early Warning System for Energy Infrastructure
Read more – Condition MonitoringCO₂ Reduction
Efficiency That Counts
Read more – CO₂ ReductionCurrent Transformer
Precise Current Measurement at Every Voltage Level
Read more – Current TransformerD
Distribution Transformer
The Last Transformer Before the Wall Socket
Read more – Distribution TransformerDistribution Transformer (ONT)
Last Transformer Before the End Consumer
Read more – Distribution Transformer (ONT)Dry-Type Transformer
Clean, Safe, Low-Maintenance
Read more – Dry-Type TransformerE
Ecodesign
The EU’s Efficiency Framework for Transformers
Read more – EcodesignF
Foil Winding
Robust Winding Technology for Modern Transformers
Read more – Foil WindingG
Generator
From Torque to Electrical Energy
Read more – GeneratorGrid Stability
The Foundation of a Reliable Power Supply
Read more – Grid StabilityH
High Voltage
Efficient Power Transmission over Long Distances
Read more – High VoltageHVDC (High-Voltage Direct Current)
Key Technology for Transcontinental Power Transmission
Read more – HVDC (High-Voltage Direct Current)I
Instrument Transformer
Precise Measurement in High- and Medium-Voltage Grids
Read more – Instrument TransformerInsulating Oil
The Invisible Heart of an Oil-Type Transformer
Read more – Insulating OilInsulation Coordination
Coordinated Protection Against Overvoltages
Read more – Insulation CoordinationJ
Joule
The Universal Unit of Energy and Work
Read more – JouleK
kVA (Kilovolt-Ampere)
The Standard Unit for Transformer Ratings
Read more – kVA (Kilovolt-Ampere)L
Low Voltage
Electricity for Households and Businesses
Read more – Low VoltageM
Medium Voltage
The Link Between Generation and Consumption
Read more – Medium VoltageN
No-Load Losses
The Invisible Energy Consumption of Every Transformer
Read more – No-Load LossesO
Oil-Type Transformer
Proven Design for High Power Ratings
Read more – Oil-Type TransformerP
Partial Discharge
An Early Warning Signal for Insulation Weak Points
Read more – Partial DischargePhase-Shifting Transformer
Controlling Power Flows in the Interconnected Grid
Read more – Phase-Shifting TransformerPhotovoltaics
Integrating Solar Energy into the Power Grid
Read more – PhotovoltaicsPower Distribution
From the Power Plant to the Wall Socket
Read more – Power DistributionPower Transformer
High-Performance Component for the Transmission Grid
Read more – Power TransformerPrimary Winding
The Transformer's Input
Read more – Primary WindingQ
Quality Assurance
Reliability Across Decades
Read more – Quality AssuranceR
Reactor Coil
Voltage Stabilizer in Power Supply
Read more – Reactor CoilRelay Protection
Guardian of the Energy Infrastructure
Read more – Relay ProtectionRenewable Energy
Transformers as the Backbone of the Energy Transition
Read more – Renewable EnergyS
Short Circuit
What Happens in the Power Grid During a Fault
Read more – Short CircuitSubstation
Node Between Voltage Levels
Read more – SubstationT
Tap Changer
Voltage Regulation in the Transformer
Read more – Tap ChangerThree-Phase Transformer
The Workhorse of Modern Power Supply
Read more – Three-Phase TransformerToroidal Transformer
Compact, Quiet, and Efficient
Read more – Toroidal TransformerTransmission Grid
The Electricity Highway Over Long Distances
Read more – Transmission GridTwo-Winding Transformer
The Classic Transformer Design
Read more – Two-Winding TransformerU
Unit Transformer
Linking Generators to the Grid
Read more – Unit TransformerV
Variable Frequency Drive
Flexibility for Motors and Grids
Read more – Variable Frequency DriveVolt
The Unit of Electrical Voltage
Read more – VoltW
Winding
The Heart of Every Transformer
Read more – WindingWye Connection (Star Connection)
Understanding Star Connections in Three-Phase Systems
Read more – Wye Connection (Star Connection)X
X-Ray Inspection
A Look Inside Without Intervention
Read more – X-Ray InspectionXLPE Insulation
Cross-Linked Polyethylene for Modern Cables
Read more – XLPE InsulationY
YNd Vector Group
Classic Configuration for Power Transformers
Read more – YNd Vector GroupZ
Zigzag Transformer
Creating a Neutral Point for Earthing
Read more – Zigzag Transformer