Transmission Systems

Due to the expansion of renewables and the dismantling of conventional power plants, the transmission systems are currently subject to major changes. In periods of high feed-in of power from renewable sources in particular, power is fed back from the distribution networks, while the load flows over long distances and the exchange of power with the network partners increases as well.

New transmission technologies and the complex characteristics of power systems without synchronous generation play a role as well. Current planning scenarios provide for the use of HVDC VSC systems for the transmission of power over long distances.

Consulting Services - Overview

  • Grid Development Plans (GDP)
  • Feasibility studies
  • Decarbonisation studies
  • Comparative AC/DC concept studies
  • Technical analyses of offshore transmission systems (AC/DC)
  • SVC, FACTS and HVDC systems (LCC/VSC)
  • Phase angle regulating transformers (demand, design, protection)
  • Concept analyses for transmission technologies (overhead lines, cables)
  • Analyses of technical problems of underground cables (Technical problems of underground cables)
  • Technical specification of equipment
  • Analyses of the reactive power demand
  • Steady-state voltage stability
  • Requirements regarding reactive power exchange with lower-level distribution networks
  • Concepts for meeting the reactive power demand (steady-state/dynamic; parallel/serial)
  • System control and operating reserve
  • Optimisation of system operation (e.g. switching sequences, maintenance processes)
  • Strategies and technical requirements for system restoration after an outage
  • Criteria for black-start capability
  • Combined system and market studies
  • Cost-benefit analyses
  • Reliability of supply as part of system security; consequences for the plant configuration
  • Analysis and assessment of steady-state and dynamic system stability, taking voltage, rotor angle, and frequency stability into account
  • Feasible stability concepts (e.g. realisation of required fault clearing times)
  • Analysis and assessment of the stability of parallel control structures in the transmission system
  • Effects of a quantitative change of rotating masses on the system
  • Determination of minimum inertia necessary for secure system operation
  • Design, control and operation of systems without synchronous generation
  • Requirements regarding the load change rates of generating units
  • Power system stabiliser (PSS) tuning
  • Analysis of grid oscillations
  • Sub-synchronous resonances (SSR)
  • Electromagnetic transient processes
  • Insulation coordination
  • Harmonics in transmission systems (sources, propagation, planning level)
  • Switchgear requirements for switching near generation (absence of zero-crossings in fault current)

Services