SuperGrid Institute brings together 180 employees of 28 different nationalities who work together within a dynamic environment in the city of Lyon. As an independent research and innovation centre, we are dedicated to developing technologies for the future power transmission system, the “SuperGrid”, including HVDC & MVDC technologies.
As a multi-disciplinary research centre with advanced simulation capabilities & multiple test platforms, including numerous associated laboratories, SuperGrid Institute uses its comprehensive expertise to provide a wide range of services and solutions to support our customers in developing power systems, equipment, and components. We specialize in system architecture and work on ensuring network security and stability while allowing for the integration of intermittent renewable energy sources. Find out more by visiting our website: www.supergrid-institute.com
Integration of large amount of renewable energy sources (RES) (e.g., offshore wind, PV) and energy market integration are two of the main drivers for the future development of the pan-European power grid. This will require a reinforcement of the transmission grid to make it able to transport large amount of power over long distances from generation areas to load areas. Extended High-Voltage Direct Current (HVDC) grids, in Point to point or Multi-Terminal (MTDC) configuration covering large areas and distances, are considered to be the preferable solution for the reinforcement of the grid. Indeed, it has been understood that MTDC grids based on voltage source converter (VSC) technology are a key development for harnessing the offshore wind production potential of the North Seas. Those systems will be evolving from simple point to point and radial structures to complex meshed ones.
Existing HVDC projects are turnkey systems, mostly point-to-point links, provided by a single manufacturer. This set-up considerably limits the extension of point-to-point links to large MTDC systems. To facilitate such projects, HVDC systems must be broken down into sub-systems that can be delivered by different vendors and must then be interoperable. Examples of such sub-systems are the AC/DC converter station, the DC switching station, and the HVDC grid control system.
Achieving multi-vendor multi-terminal HVDC interoperability is identified as a key target by the European Commission. The Horizon Europe InterOPERA project proposal is a unique initiative to define and validate the appropriate HVDC Interoperability frameworks, through the development of a real-time Demonstrator. It encompasses functional design and specification frameworks, control and protection subsystems integration test frameworks, cooperation frameworks, procurement frameworks. The Demonstrator development consists of the specification, engineering development and HIL (Hardware-In-the-Loop) integration test of the full control system of a multi-terminal HVDC grid with sub-systems provided by at least three HVDC manufacturers. This is a four-year project gathering 21 partners (Transmission System Operators, Off-Shore Wind developers, HVDC converter manufacturers, Off-shore wind turbine manufacturers, …).
Within the InterOPERA project, SuperGrid Institute will lead the development of a generic functional framework, for multiterminal multivendor HVDC systems. The objective of the functional design framework is the following: A/ to define functional split and interface between the various sub-systems (some control and protection functions belong to the DC grid level and others belong to converter station level or to other components), B/ to express functional requirements and parameter ranges for each subsystem, with the aim to maximise interoperability (plug and play property) while not limiting innovation potential by subsystem providers. The interoperability subject relates to control and protection functions organization, at system level, subsystem level, component level. During the first two years of the project, SuperGrid will lead Task 2.1 – Basic functional requirements for multi-vendor HVDC Grid Systems and Subsystems. During the last two years of the project, SuperGrid will contribute to Task 2.3 – Connection network code recommendations for multi-vendor multi-terminal HVDC systems.
To support this work SuperGrid Institute plans to hire a research engineer who will carry out a PhD project related to the AC-side interoperability of multivendor multiterminal HVDC grids. The PhD project will especially address research issues that couldn’t be handled by the main operational resources of InterOPERA project Task 2.1, due to demonstrator-focused priorities, but remain important to be addressed before the conclusion of the InterOPERA project. Such research issues raised by Task2.1 will be processed through the PhD project, to contribute to Task2.3 and to project final conclusions.
PhD topic description
HVDC interoperability can be classified into DC-side interoperability and AC-side interoperability. Whereas all converters belonging to a given DC grid must be interoperable on their DC-side, AC-side interoperability is not always a concern, this depends on AC-side system and configuration.
Nowadays, a HVDC converter connected to an offshore wind farm grid is controlled to form the AC wind farm grid frequency and evacuate the power generated by the farm: this control is often named Vf control. A single HVDC converter is connected to a single wind farm. Moving forward, new offshore wind will be connected through 2GW bipolar HVDC scheme, instead of 900MW monopolar HVDC scheme. It may then be beneficial for wind farm operation (availabity optimization), to interconnect through their AC-side, the positive pole converter and the negative pole converter. Both converters would then share the grid forming duty and the evacuation of the power, leading to AC-side interoperability issue (#1).
Down the road, HVDC-connected OWF will be required to provide onshore grid forming services. This requirement will lead to a new way of operating the OWF AC grid. Wind turbine converter will have to adjust their power output to the dynamic demand from the onshore side. In such scheme, the offshore HVDC converter and the Wind Turbine converters would need to cooperate, leading to AC-side interoperability issue (#2).
The PhD project may address this background context, as well as complementary scientific issues that would be raised during InterOPERA project.
Work objectives and content will be defined according to Task2.1 inputs and research issues that are relevant to select for the PhD project, considering InterOPERA project aim.
Research work will call for:
- Bibliography and state of the art analysis
- Selection of scientific locks and research issues
- Electro-Magnetic-Transient (EMT) modelling of the HVDC system and the OWF system with its protection and controls,
- Theoretical approach of AC-side stability issues, based on simplified models,
- Formalization of AC-side control framework concepts and options
- Assessment of AC-side control framework options, also taking DC-side constraints into account
- Key findings validation, possibly on Supergrid HIL Simulation Platform
 Düllmann P. , et Al.: European Offshore grid : On protection system design for radial bipolar multi-terminal HVDC networks – Publication 11087 CIGRE Paris 2022
 Equinor : multivendor hvdc links providing O&G installations, perspectives and challenges – https://ec.europa.eu/energy/sites/ener/files/documents/10._sharifabadi_kamran_-_multivendor_hvdc_links_supplying_oil_and_gas_installations.pdf
Engineering degree (Master 2)
Background required in Electrical engineering
- Power System
- Power Electronics
- Control Engineering
Sens of deduction, ability to work within a research team
Written and oral communication in English
The application must be sent at the following address : firstname.lastname@example.org and has to include the job title, candidate name, CV and the most recent marks.
SuperGrid Institute is an equal opportunities employer. We respect and value the diversity of our employees, their backgrounds and their professional experience. We believe in equality and take affirmative action to ensure that discrimination has no place in our recruitment process nor our company.