High voltage testing laboratory

Performing AC & DC investigation and type tests

SuperGrid Institute’s high voltage testing laboratory is a unique set of capabilities to perform DC and AC tests.

It comprises an indoor 700m² Faraday cage for ultra high voltage (UHV) tests and several shielded areas to perform medium voltage, high voltage and ageing tests.

The set of equipment, including generators and monitoring assets, is mobile to adapt at best to specific requests.

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High voltage testing services include:

Definition of test protocols & test set-ups
Test execution
Test reports
Test result analysis & expertise

Field of application:

MVAC, MVDC, HVAC, HVDC

Tested equipment include:

Cable systems
AIS and GIS

Model-scale equipment and prototypes

Technical brochure

The set of platforms includes

An indoor Ultra High Voltage (UHV) test platform
Two indoor 20m² shielded rooms for lower voltage tests (up to 400kV)
An outdoor platform dedicated for long-term ageing tests on GIS / AIS

Test capabilities

HVDC cables and HVDC GIS electrical type tests
Low signal measurements including partial discharges (PD)
Dielectric DC and AC tests (combined with thermal conditioning)
Switching (SI) and lightining (Li) impulse tests
Transient overvotalge (TOV) tests
Dielectric combined voltage tests (BIAS)
Superimposed tests (SUIMP)
Breakdown tests
Long-term thermal and electrical ageing tests
Characterisation of gas, liquid and solid insulation

Other tests upon request.

Nexans and SuperGrid Institute perform their first TOV test on a 525kV DC cable system

Damped oscillations TOV testing 525kv dc at SuperGrid Institute

TOV tests for DC cables – up to 525 kV

SuperGrid Institute is one of the few institutes in Europe performing Transient Over Voltage (TOV) tests on DC cable systems up to 525 kV.

Unique test capabilities validated with Nexans on a 525 kV DC cable system.
Guarantee your HVDC cables withstand disruptive events such as converter station faults or grounding failures.
Strengthen the reliability and durability of your DC cables in real operating conditions.

Our references

Nexans and SuperGrid Institute successfully carried out a first Transient Overvoltage (TOV) test on a 525 kV DC cable system, consisting of two external terminations, two joints and an extruded DC cable. The DC cable system passed several sequences of zero-crossing damped over voltage tests at both 350 Hz and 6 kHz (see graph).

SuperGrid Institute is fully prepared to support European DC cable system manufacturers in the qualification of 525 kV DC cable systems by conducting extended type test programs, as required by Transmission System Operators (TSOs).

HVDC cable testing expertise at Jicable HVDC'25

Ultra high voltage test platform

Our high voltage test platforms are among the most advanced in Europe and can be adapted to specific applications for cable manufacturers.

Faraday cage:
- 700 m², separable into two test areas (GIS, AIS, cable systems).
- Ultra-low PD levels, leakage current monitoring, UHF/UV/ultrasound instruments.
HVDC sources:
up to 1200 kV, 20 mA, low partial discharge levels.
HVAC sources:
up to 750 kV AC
Impulse generator:
up to 2000 kV, with flexible adjustment.

General main features of the high voltage test platforms

Equipment	Specification	Other features
DC Sources	Up to 200kV Up to 400kV	Easy use and handling Direct cable connection up to 200kV Polarity reversal Well-suited for R&D basic tests
HVDC Sources	Up to 800kV, 30mA Up to 1200kV, 20mA	With polarity reversal Slope adjustment from 1 to 20 kV/s Low partial discharge level, below 800fC at rated voltage
HVAC Source	Up to 660kV	Slope adjustment from 1 to 16 kV/s Fast switch-off unit available Possibility to test cable length up to 15m with compensation systems
HVAC & HVDC metal clad source	Up to 750kV AC Up to 850kV DC	Well-suited for long-terme / ageing tests Low PD level Access to outdoor test field (L 11m x W 11 m x H 15m)
Impulse generator	Up to 2000kV 200kJ	Possibility to adjust the generator to deliver impulses from 20kV to 2000kV BIAS and superimposed compliant

Measurements & Monitoring

Voltage measurements are performed with factory calibrated dividers. All our HVDC generators have embedded RC dividers. Two additional PD-free dividers can be positioned to accommodate different test set-ups:

Universal divider, up to 2000kV LI, 1400kV SI, 1000kV DC, 700kV AC
Capacitive divider up to 800kV AC, with embedded PD measuring impedance

Specific measurements can be carried out with scientific instruments available in the laboratory (UHF systems, UV systems, Ultrasounds, electrometers, high speed camera…)