News Release

Kawasaki, Japan – Toshiba Energy Systems & Solutions Corporation (Toshiba) has received an order from J-POWER Transmission Network Co., Ltd., for the design, procurement, and installation of a voltage-sourced converter (VSC) high-voltage direct current (HVDC) system, comprising converters, transformers, and control and protection systems and other components, for the renewal of Pole 1 of the Hokkaido-Honshu HVDC Link.

The Hokkaido-Honshu HVDC Link is the core transmission facility connecting the power grids of Hokkaido and Honshu, via a 167-kilometer transmission line. Efficient and stable long-distance power transmission along its length, including a 43 km submarine section under the Tsugaru Strait, is secured with an HVDC system that converts alternating current (AC) into direct current (DC) for transmission, and then converts it back to AC at the receiving end. Toshiba plans to start sequential delivery of the equipment from fiscal year 2029, in readiness for commercial operation, which is scheduled to begin during fiscal year 2031, following on-site testing and commissioning.

Currently, the total interconnection capacity between Hokkaido and Honshu is 900 MW: 600 MW from the Hokkaido-Honshu HVDC Link (300 MW for each of Poles 1 and 2), and 300 MW from Pole 1 of the New Hokkaido-Honshu HVDC Link. Capacity will increase by a further 300 MW when Pole 2 of the New Hokkaido-Honshu HVDC Link is completed. However, Pole 1 was commissioned in 1979, and after over 45 years operation its key equipment is aging and needs replacement.

The link connects the Hakodate Converter Station in Hokkaido and the Kamikita Converter Station in Aomori Prefecture via DC transmission lines, and plays a vital role in interconnecting the power systems of Hokkaido and Honshu. In the replacement project, VSC-HVDC equipment supplied by Toshiba will be installed in both converter stations.

The VSC-HVDC system to be employed in Pole 1 is self-commutating, ensuring stable power interchange even when the voltage of the connected AC grid is unstable. As Pole 2 of the Hokkaido-Honshu HVDC Link continues to employ an LCC-HVDC system, the renewed interconnection will feature a hybrid configuration combining VSC and LCC technologies.

Toshiba has been involved in all power interconnection facilities linking Hokkaido and Honshu. The company supplied HVDC systems for the Hokkaido-Honshu HVDC Link and Pole 1 of the New Hokkaido-Honshu HVDC Link, and won the contract for the VSC-HVDC system for Pole 2 of the New Hokkaido-Honshu HVDC Link, which is currently under construction. The VSC-HVDC converter for the renewal project is the same design as the one that will be supplied for Pole 2 of the New Hokkaido-Honshu HVDC Link. It leverages proven reliability and quality, and will contribute to a stable power supply.

With the worldwide expansion of renewable energy, demand for power system interconnection technologies, including HVDC, continues to grow. Through its expertise and track record in HVDC technologies, Toshiba will continue to provide high-quality products and solutions in Japan and internationally, contributing to the realization of stable and reliable power supplies over wide areas.