Hitachi Energy unveils AxoniQ: game-changing solution for the next era of transmission grids

Hitachi Energy, a global leader in electrification, today announced the launch of AxoniQ™, its comprehensive portfolio of solutions for multi-terminal direct current (MTDC) systems. As global electricity demand accelerates, MTDC systems are becoming critical to ensuring a secure, affordable, and sustainable power grid.

As renewable energy deployment accelerates and power systems become increasingly interconnected, MTDC systems help manage congestion and improve resilience by allowing dynamic power flow between multiple terminals and across different energy markets, while supporting faster planning, procurement, and execution of grid projects. By connecting multiple power sources and demand points, MTDC grids enable electricity to be directed where it is needed most.

ENTSO E’s Offshore Network Development Plans 2024 report¹ highlights that by 2040, Europe is moving into a massive scale‑up phase of offshore renewables, which requires major transmission expansion and early hybrid grids. Grids developed with MTDC systems can boost transmission capacity up to nearly threefold in a 2040 scenario.

Achieving the same capacity and reliability without these solutions would require substantial capital investment. Optimized assets not only translate into fewer converter stations, but also into fewer power cables and lines and a reduced use of land and materials, underpinning a more sustainable energy system for the benefit of both society and the environment.

Marking a significant step toward greater interoperability, the launch of AxoniQ comes as governments and grid operators worldwide accelerate investments in transmission infrastructure toward a fully electrified world to integrate renewable energy at scale, strengthen cross-border interconnections, and improve energy security.

The AxoniQ portfolio combines advanced power electronics and control technologies. It includes:

• AxoniQ Protect: An innovative solution that can interrupt a DC fault in less than three milliseconds, it offers fast and effective protection at up to 525 kilovolts (kV). It enables selective fault isolation by disconnecting only the affected section of the DC grid, while the rest of the system continues operating. This continuous, proactive protection enables extremely low losses and the optimal combination of performance, efficiency, and reliability throughout the entire lifecycle.
• AxoniQ Connect: A modular DC switching station that enables the connection of new terminals and structures the grid into several protection zones, creating manageable subsystems. AxoniQ Connect ensures reliable service continuity, simplifies maintenance, and supports cost-efficient scalability.
• AxoniQ Control: An advanced control system built with interoperability in mind that maintains voltage stability and power balance, optimized power flow, and flexible, market-driven energy exchange. AxoniQ Control addresses congestion and enables quick reconfigurations in the event of disturbances.

Together, the AxoniQ suite of cutting-edge power electronics solutions enables the re-routing of power in real time, rapid fault isolation, and maintaining continuity of power supply while minimizing the impact on the wider grid and avoiding the risk of costly power interruptions.

Engineered for interoperability by design, AxoniQ will continue to evolve to enable a sustainable expansion of direct current (DC) grids in the decades ahead.

The AxoniQ family is part of Hitachi Energy’s Grid-enSure®, a fully integrated solution portfolio to stabilize power systems by strengthening transmission, managing frequency variations and system voltage and addressing capacity constraints. AxoniQ takes its name from axons, the part of a nerve cell (neuron) that carries electrical signals away from the cell body to other neurons, muscles or glands, effectively functioning as the body’s electrical system. Like axons, AxoniQ brings power to life across the grid – intelligently and effectively transmitting electricity between multiple sources and demand points, acting as the vital connection that enables a more responsive, resilient, and interconnected energy system.

AxoniQ has been researched and developed by Hitachi Energy for more than a decade, and its benefits are demonstrated through the company’s work in partnership with TSOs and main industry players with the aim of making future HVDC systems mutually compatible and interoperable by design.