Contributing to the stable supply of energy

In this Project, the system to be delivered uses Voltage Source Converter (VSC) High-Voltage Direct Current Transmission (HVDC) power transmission technology, enabling interconnection between systems with different frequencies implemented by converting alternate current into direct current. Hitachi will construct the system with the combination of an ABB HVDC converter together with control and protection system and Hitachi converter transformers based on the strategic partnership with ABB.

In the Great East Japan Earthquake that occurred on March 11th, 2011, many large-scale power supplies were lost in areas where power was supplied by power companies in the Tohoku and Kanto regions. The situation required scheduled outages in some areas in the Kanto region because of the restricted capacity of the power interconnection lines on the amount of power interchange from other power company areas.

To prevent this issue from reoccurring, the Organization for Cross-regional Coordination of Transmission Operators, Japan, which supervises the power interchange among power companies, has been advancing a priority project to increase the interconnection capacity between the 60Hz area of Chubu Electric and the 50Hz area of Tokyo Electric Power Grid (TEPCO) from the current 1,200MW to 3,000MW.

Chubu Electric has been developing an important project for increasing the interconnection capacity of the Higashi Shimizu Substation from 300 to 900MW, which is scheduled to commence operation in FY2027.

This Project employs VSC-HVDC technology with fewer restrictions on the operation of system interconnection, which is capable of implementing a black start even if one of the systems loses its power supply.

Compared to Line Communicated Converter High-Voltage Direct Current Transmission (LCC-HVDC) technology that has been used so far, VSC-HVDC technology can control the active power and reactive power in the system separately, which enables downsizing of peripheral devices such as the phase modifying equipment and reduction of the installation area. It is a new technology that can be expected to stabilise effect on the power system.

In most HVDC projects installed within Japan, Hitachi has taken charge of the technical development and arrangement of the projects, contributing to HVDC, which has operated to maintain Japan's high power quality and high availability.

Atsushi Oda, Senior Vice President and Executive Officer, in charge of Nuclear Energy Business and Energy Business, said: “Hitachi is scheduled to acquire the power grid business company from ABB through an 80.1% investment around the first half of 2020, and considers the HVDC business as one of Hitachi's main businesses. Moving forward, Hitachi will respond to the need for system interconnection equipment involved in enhancing system interconnection and the increased use of renewable energy that is predicted to occur in Japan in the future, contributing to the enhancement of system interconnection in Japan and overseas.”