The world largest HV cable monitoring project!

Monday, 19 September 2016 08:33 | Written by 

Techimp is proud to announce its last outstanding achievement.

12x 10 km of 380kV-Cable in the West of the Netherlands to be monitored with a single system!

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BACKGROUND
The behavior of transients in high voltage cables is matter of concern, especially when overhead lines alternates with cable links. 
In a 380 kV link with so many cable accessories it is essential to keep track of the reliability of these accessories. Especially, in the case of transients (switching, lightning), partial discharge (PD) could potentially be triggered. In case the PD is sustained, accelerated insulation degradation could hamper component reliability.

NEEDS
A Monitoring System capable to synchronize the information from the monitoring of voltage and current transients in different parts of the system with PD activity in the accessories, would be fundamental.
It was decided to design and install an Advanced Condition Monitoring System to acquire, validate and present values of parameters that represent:

  • The behavior of the cables in the network
  • The influence of these cables on the network stability

 

AWARDING
In 2015 TenneT (leading European electricity transmission system operator with activities in Netherlands and Germany) commissioned to Techimp one of the bigger and innovative high voltage power network monitoring system in the world.


What we have done!
THE WORLD LARGEST HV CABLE MONITORING PROJECT

PURPOSE & ACHIEVEMENT

  • Collect evidences of the behavior of a combined transmission cable/overhead line and confirmation of the mathematical model in transient regime
  • Obtain a possible indicator of the degradation of the system (residual lifetime) as a result of transients occurring in time

A UNIQUE SYNCHRONOUS GLOBAL MONITORING SYSTEM WITH UNRIVALLED PERFORMANCES:

  • Partial discharge acquired signal frequency: 500MHz (against the standard 50MHz)
  • Transients phenomena acquired signal frequency: 1 MHz (against the standard 20kHz)
  • 0.2% (class 0.2) Accuracy
  • <100ns Time stamp
  • 2000+ Electric Boards
  • 1000+ Sensors
  • 8000+ Measured Variables

CUSTOMER BENEFIT PACKAGE

  • Synchronous global monitoring of critical (cable) system parameters allows:
  • Learning about the behavior of new topologies of HV cable systems that have not been proven yet;
  • Optimizing the economic use of the system through knowledge of the state of the critical components;
  • Validating the results of system studies through monitoring transients and synchronizing the measurements at different locations in the system;
  • Checking whether transients may lead to partial discharge induced accelerated ageing;
  • Reducing downtimes and unforeseen non-availability.

KEY TECHNICAL ASPECTS:
A full understanding of oscillating and transient phenomena at Substations, Transition Points, and Joint Bays:

@ Substations

  • Line (RMS) and Transient Voltage Measure
  • Line (RMS) and Transient Current Measure

@ Transition Points

  • Phase (RMS) and Transient Voltage Measure
  • Phase (RMS) and Transient Current Measure
  • Surge Arrester current
  • Surge Arrester leakage current
  • PD on Cable Termination

@ Joint Bays

  • Cross Bonding Voltage
  • PD Signal
  • Screen Current