Publiée 19 août 2026
Internship - Overvoltage calculations in metallic return cable for HVDC grids W/M
SuperGrid Institute
Villeurbanne, Auvergne-Rhône-Alpes 69100, France
CDI
Description
Established in 2014, SuperGrid Institute is an independent private company with over 150 employees of 21 different nationalities. The institute is a key player for energy transition in France and throughout Europe, specialising in innovative high and medium voltage direct current (HVDC and MVDC) power systems. SuperGrid Institute also develops new technologies for the integration of renewable energies into the electricity networks of the future.
SuperGrid Institute has been ranked every year since 2018, reaching the podium 3 times in the INPI prize list.
Find out more by visiting our website: www.supergrid-institute.com
Key words: Insulation Coordination / Multi Terminal DC grid / HVDC
General Context
Extended HVDC (High Voltage Direct Current) networks, covering large areas and long distances, are considered the most suitable solution for integrating renewable energy sources and strengthening the security of the electrical system. In Europe, several radial HVDC networks are expected to be installed over the next decade.
In HVDC links, the return current must flow through a defined path. During monopolar operation, a dedicated metallic return cable (DMR) is often used instead of ground return in order to avoid corrosion and environmental impacts. However, this configuration introduces new challenges related to overvoltages that may occur during faults, converter blocking, or switching operations. These transient overvoltages can stress the insulation of the metallic return cable and associated equipment, affecting the reliability and lifetime of the system.
Understanding and predicting these phenomena requires detailed electromagnetic transient studies that take into account cable parameters, grounding schemes, and interactions with the system. Accurate calculation of overvoltages in the DMR is therefore essential for insulation coordination and for the safe and reliable operation of current and future HVDC networks.
Missions
Tasks
• Literature review and state-of-the-art study on HVDC systems, including point-to-point links and multi-terminal DC networks, with a particular focus on the operation of bipolar HVDC systems using a dedicated metallic return cable (DMR) and the associated operational challenges.
• Familiarization with EMT software for insulation coordination (EMTP training).
• Modeling of HVDC system components (HVDC converter, transmission line, and fault modeling).
• Performing simulations to calculate transient overvoltages in the DMR cable for different fault and switching scenarios.
• Sensitivity analysis of parameters: evaluation of the influence of cable length, system architecture and configuration, grounding resistance, and coupling with other conductors on overvoltage levels.
• Identification of the most critical parameters affecting the insulation stress of the DMR cable.
Profil
Candidate Profile
Master or engineering school student in the last year of her/his studies. The student must have good knowledge of the following fields: Electrical engineering, power network, transmission lines. Fluency in English is mandatory.
Start date: from September 2026
Duration: 6 months
Soft skills
What we can offer you:
Other information
At SuperGrid Institute, we respect and value the diversity of our employees, their backgrounds and experiences, with the aim of providing equal opportunities for all. Diversity is at the heart of our operations, and we are committed to banning all discrimination from our human resources management. SuperGrid Institute makes all its positions accessible to people with disabilities and is committed, as part of its action plan for professional equality, to paying particular attention to applications from women in order to achieve a balanced overall distribution of the workforce.
Established in 2014, SuperGrid Institute is an independent private company with over 150 employees of 21 different nationalities. The institute is a key player for energy transition in France and throughout Europe, specialising in innovative high and medium voltage direct current (HVDC and MVDC) power systems. SuperGrid Institute also develops new technologies for the integration of renewable energies into the electricity networks of the future.
SuperGrid Institute has been ranked every year since 2018, reaching the podium 3 times in the INPI prize list.
Find out more by visiting our website: www.supergrid-institute.com
Key words: Insulation Coordination / Multi Terminal DC grid / HVDC
General Context
Extended HVDC (High Voltage Direct Current) networks, covering large areas and long distances, are considered the most suitable solution for integrating renewable energy sources and strengthening the security of the electrical system. In Europe, several radial HVDC networks are expected to be installed over the next decade.
In HVDC links, the return current must flow through a defined path. During monopolar operation, a dedicated metallic return cable (DMR) is often used instead of ground return in order to avoid corrosion and environmental impacts. However, this configuration introduces new challenges related to overvoltages that may occur during faults, converter blocking, or switching operations. These transient overvoltages can stress the insulation of the metallic return cable and associated equipment, affecting the reliability and lifetime of the system.
Understanding and predicting these phenomena requires detailed electromagnetic transient studies that take into account cable parameters, grounding schemes, and interactions with the system. Accurate calculation of overvoltages in the DMR is therefore essential for insulation coordination and for the safe and reliable operation of current and future HVDC networks.
Missions
Tasks
• Literature review and state-of-the-art study on HVDC systems, including point-to-point links and multi-terminal DC networks, with a particular focus on the operation of bipolar HVDC systems using a dedicated metallic return cable (DMR) and the associated operational challenges.
• Familiarization with EMT software for insulation coordination (EMTP training).
• Modeling of HVDC system components (HVDC converter, transmission line, and fault modeling).
• Performing simulations to calculate transient overvoltages in the DMR cable for different fault and switching scenarios.
• Sensitivity analysis of parameters: evaluation of the influence of cable length, system architecture and configuration, grounding resistance, and coupling with other conductors on overvoltage levels.
• Identification of the most critical parameters affecting the insulation stress of the DMR cable.
Profil
Candidate Profile
Master or engineering school student in the last year of her/his studies. The student must have good knowledge of the following fields: Electrical engineering, power network, transmission lines. Fluency in English is mandatory.
Start date: from September 2026
Duration: 6 months
Soft skills
- Teamwork
- Good communication skills
- Organizational skills
What we can offer you:
- You will be joining an institute dedicated to the energy transition, a promising and stimulating field of activity,
- Participation in meal expenses (company restaurant),
- Activities between colleagues within the company (football, running, choir, etc.),
- CSE,
- Electrical approvals covered,
- Self-service bicycles.
Other information
At SuperGrid Institute, we respect and value the diversity of our employees, their backgrounds and experiences, with the aim of providing equal opportunities for all. Diversity is at the heart of our operations, and we are committed to banning all discrimination from our human resources management. SuperGrid Institute makes all its positions accessible to people with disabilities and is committed, as part of its action plan for professional equality, to paying particular attention to applications from women in order to achieve a balanced overall distribution of the workforce.
