In order to facilitate the transition towards renewable energy, the Dutch power grid will need to be operated towards its limits. This poses the risk of increased number of failures and accelerated ageing of grid components. To mitigate this risk, real-time insight in the present and future state of the grid is necessary. This will allow Alliander to connect more customers to the grid while ensuring that the grid remains safe, reliable and green.
For underground power cables, the maximum current is determined by the cable temperature. The present method of determining this maximum relies on overly simplistic and conservative assumptions. For example, load is assumed constant which is unrealistic for solar- and windparks. In order to safely use more accurate dynamic models for cable temperature, realistic estimates of the model uncertainty are necessary to ensure that cable temperatures always remain within safe limits. This is where you come in.
In this position you will divide your time between working at Alliander, and doing strongly related research at the Radboud University.
Proposed PhD research topic
To make accurate and robust predictions of the cable temperature, it is necessary to take into account the uncertainties involved in its functioning. There are many sources of uncertainty, among which:
geometry, for example the depth of cable circuits in the soil, the distance between cable circuits and the thickness of the coating around the cable;
boundary conditions, for example the surface temperature of the soil;
ground resistivity, which can be modeled either as a single uncertain, scalar parameter, or, with higher resolution, as an uncertain function (random field);
forcing, coming from the load in the cable;
the role of ground humidity.
In order to incorporate uncertainties in the model, we need to solve two main tasks: given an initial estimate of the uncertainties in the parameters, we have to study how these affect the temperature distribution of the cable (forward problem); furthermore, using the knowledge provided by measurement data, we can obtain more accurate estimates of the uncertainties in the parameters (inverse problem), which can in turn be used for prediction in the forward problem. According to the skills and interests of the candidate, the project will focus more either on the forward or on the inverse problem.
A feature to exploit in both tasks is the presence of a hierarchy of models for the temperature distribution in the cable. These range from a basic zeroth order model where cable temperature is modelled as a single variable, through the basic finite difference model, to a complex finite element model that includes local permeabilities and ground resistivities (as random fields), and time dependent geometry (the coating of the cable). In our algorithms, we will exploit such hierarchy and combine different model resolutions to enhance computational efficiency while retaining high accuracy in the results.
A more detailed description of the proposed research is available upon request, see the contact details below. Your academic supervisors from Radboud University will be prof. Gabriel Lord and dr. Laura Scarabosio of the Applied Mathematics group.
Your work as an energy data expert at Alliander
At Alliander, you will work in the Grid Quality Management team, which is part of the System Operations department. This is a multi-disciplinary scrum team consisting of data scientists, software engineers and energy experts. Here you will help on implementing the mathematical models coming from your PhD research directly into the IT systems used for grid operations. In this way, your models will use real field data and the model results can be used directly to get insight into the power grid. The goal is to enable Alliander to realize customer connections without making major capital investments.
An MSc degree in (applied) mathematics, physics, or a related field.
Computational experience: numerical methods for partial differential equations.
Proficient in programming languages used in scientific computing, such as Python and a willingness to develop programming skills further.
Fluency in verbal and written English.
Excellent communication, presentation and writing skills.
Comfortable in working in multi-disciplinary team.
Your working conditions
You have the energy, we give you the space – the space to get the best out of yourself. Because that benefits everyone: you, Alliander and most of all our customers. And there's more. In this role, you can expect (based on a 38-hour working week):
A gross monthly salary of up to € 4.530, - (scale 8).
A permanent contract after one year.
A Personal Budget of 18% of your annual salary on a full-time basis. You can choose to have this paid out, to purchase extra leave days or to pay it into your pension.
An allowance of 70% of the statutory minimum wage for parental leave hours. This applies if you take parental leave after one year of service.
36 hours (4.5 days) extra saved leave each year. You can use this leave or save it for up to 10 years for a sabbatical etc.
A long-term employability budget of €500. You can use this for career development, a gym membership and/or ergonomic home office furniture etc.
A pension at ABP. Alliander pays 70% of your pension premium.
A fixed year-end bonus of 5.94%.
Alliander offers you plenty of space and opportunities for development. We work with the best trainers in the Netherlands. You can choose from a wide range of training courses, workshops, study programmes, study books, webinars and e-learning modules.
An NS Business Card or a mileage allowance if you travel by car.
A gross contribution of €360 and discounts on supplementary insurance if you have a collective health insurance policy with Zilveren Kruis Achmea.
A laptop and mobile phone, or Bring Your Own Device.
You'll be surprised by the excellent working conditions at Alliander. We have listed them for you at https://werkenbij.alliander.com/arbeidsvoorwaarden
Alliander screens all applicants. Depending on the position, the screening consists of the following steps: checking references, checking the authenticity of identity papers and diplomas, an integrity check and requesting a certificate of conduct (VOG).