IN Brief:
- Redeia has validated anti-cascading transmission tower behaviour using advanced dynamic simulation.
- The work assessed extreme sequential collapse scenarios affecting high-voltage overhead lines.
- The project supports more detailed resilience assessment as transmission networks face harsher operating conditions.
Redeia has completed advanced simulation work to assess the behaviour of anti-cascading towers on high-voltage overhead transmission lines under extreme structural failure scenarios.
The project was developed through Redeia’s technology platform Elewit in partnership with engineering software specialist Akselos. It assessed anti-cascading tower performance under sequential multi-tower collapse conditions, using dynamic simulation methods rather than relying only on static analysis.
Anti-cascading towers are reinforced structures installed at strategic points along overhead line routes. Their purpose is to prevent a local structural failure from propagating across a wider section of the network. If adjacent towers fail because of extreme weather, external impact, or another critical incident, the reinforced tower must absorb abnormal conductor tensions and stop progressive collapse.
That function is becoming more demanding as high-voltage corridors carry greater system value. Transmission lines are exposed to wind, temperature, ice, wildfire risk, ground movement, vegetation, and external interference. When renewable generation and electrified demand increase, the operational consequences of losing a major corridor become more severe.
The simulation work focused on dynamic behaviour during extreme events. Static models can assess loads under defined conditions, but they may not fully capture the transient effects created when one structure fails and conductor loads redistribute rapidly through insulators, fittings, foundations, and neighbouring towers. Multi-tower failure scenarios can involve vibration, shock loading, rapid stress transfer, and complex mechanical interaction.
Akselos’ finite element modelling approach was used to develop high-fidelity simulations while reducing the computational burden normally associated with detailed structural analysis. For transmission operators, faster and more detailed modelling can support asset assessment, design validation, maintenance planning, and future reinforcement strategies.
The project confirmed the effectiveness of current Spanish design standards for mitigating cascading failures across the transmission network. That gives Redeia a stronger technical basis for applying existing criteria while assessing how overhead line assets behave under extreme conditions.
Transmission operators across Europe are having to align renewable growth with network capability. The warning from Balkan transmission system operators that grids must keep pace with renewables growth reflects the same structural pressure, although Redeia’s project focuses on physical resilience rather than cross-border capacity or market integration.
Transmission resilience is often discussed through cyber security, system stability, or generation adequacy. Physical asset resilience carries equal weight. A tower, conductor, insulator string, foundation, or fitting failure can remove a circuit from service, constrain power flows, create safety hazards, and trigger wider system management actions. Where a line forms part of a critical corridor, structural performance becomes part of system operation.
Advanced simulation can also inform future design choices. Better modelling of dynamic failure behaviour can help operators refine where reinforced towers are installed, how much additional structural capacity is justified, and which existing assets require closer inspection or strengthening. That can improve resilience without applying excessive reinforcement across entire routes.
The project also demonstrates the growing role of digital tools in asset management. Transmission operators are increasingly using detailed models, sensor data, digital twins, and predictive analytics to assess assets under conditions that are difficult or impossible to test physically. These tools do not replace engineering judgement, but they can improve the evidence base behind standards, maintenance decisions, and investment planning.
Spain’s transmission network is operating within a power system shaped by renewable growth, interconnection, and closer scrutiny of system resilience. Structural modelling of anti-cascading towers is a specific technical exercise, but it supports a wider requirement: ensuring that the physical network can tolerate exceptional events without disproportionate system consequences.
The validation work gives Redeia a stronger technical foundation for resilience planning across high-voltage overhead lines. As European transmission networks expand and face greater environmental and electrical stress, the ability to model asset behaviour under extreme conditions will become a more valuable part of grid engineering practice.
