LS Cable & System Passes 525 kV HVDC PQ Test

LS Cable & System has passed the pre-qualification test for 525 kV, 80°C-class HVDC submarine cables, becoming the first company in Korea to achieve the certification. The company announced the milestone on 9 July 2026, following a one-year testing programme that validates the long-term performance and reliability of the extruded cross-linked polyethylene (XLPE) cables for voltage-source converter HVDC systems.

The pre-qualification process is an international certification that allows suppliers to deliver products after completing only a type test once a contract is awarded. The test was conducted to TenneT TSO B.V. specifications and aligned with CIGRE TB-496 and IEC 62895 standards.

Technical Specifications and Performance

The new 525 kV submarine cables operate at an allowable conductor temperature of 80°C, compared to 70°C for previous-generation products. The increase in operating temperature raises transmission capacity by up to 25 percent, enabling power flows exceeding 2 GW. LS Cable & System described the cables as a next-generation product incorporating extra-high-voltage insulation technology and long-term reliability suitable for long-distance, large-capacity power transmission.

West Coast Energy Highway Application

The pre-qualification positions LS Cable & System to supply 525 kV, 80°C-class submarine cables for Korea's West Coast Energy Highway project, a planned high-voltage direct current corridor along the country's western coast. The project is among the initiatives driving demand for advanced HVDC infrastructure in Korea as the country expands renewable energy integration and upgrades its national transmission network.

LS Cable & System is currently the only Korean company with a commercial track record in HVDC submarine cable supply. The company has delivered HVDC cables for the Jeju 2 and Jeju 3 interconnection projects linking Jeju Island to the Korean mainland, and supplied cables for TenneT's European grid projects, including a $1.5 billion contract awarded in 2022 following an earlier pre-qualification test completed in October 2022.

Market Context and Subsidiary Activity

Demand for long-distance, large-capacity HVDC transmission infrastructure is accelerating globally, driven by the expansion of renewable energy generation and the proliferation of artificial intelligence data centres. The certification strengthens LS Cable & System's position in the domestic and international HVDC markets, where it competes with established suppliers including Prysmian and Nexans, both of which completed 525 kV HVDC extruded submarine cable pre-qualification tests in 2022 and recently, respectively, under similar international standards.

A company spokesperson stated that passing the pre-qualification test represents an important milestone for targeting the next-generation national power grid market. The spokesperson added that LS Cable & System will leverage its turnkey manufacturing and construction capabilities alongside LS Marine Solution to expand into the energy highway and global HVDC markets.

Within the LS Cable & System group, subsidiaries are strengthening their capabilities in the power infrastructure sector. LS Eco Energy recently completed the pre-qualification test for 400 kV extra-high-voltage cables for the North American market, while Gaon Cable has developed extra-high-voltage cables meeting Korea Electric Power Corporation specifications and is scheduled to begin supplying them in 2027.