Ronnie Belmans

KU Leuven | ku leuven · Department of Electrical Engineering (ESAT)

An overall model and scenario for increasing the share of renewable electricity consumption in the Belgium grid is proposed by simulating different PV and home battery capacities. The model is balancing the electricity generation of these renewable sources on an hourly basis with the historical consumption profiles of 2014, 2015, and 2016 to estima...

The European Internal Energy Market consists of many interconnected market zones. Unless transmission capacities are constrained, these market zones share capacity assets and injected energy to the benefit of the system. Market and price coupling allows making use of resources more efficiently. These efficiency gains are grounded on the harmonizati...

Increased shares of Renewable Energy Sources (RES) to fulfill ambitious European policy targets, mothballing or decommissioning of existing units, and absent investments lead to concerns about the system and market adequacy. To restore market adequacy, capacity mechanisms (CMs) are widely discussed and implemented in various types. They are intende...

This paper presents a comprehensive modeling framework to analyze and compare the performance of different voltage droop control characteristics in an HVDC grid. All models are fully derived mathematically, both for dynamic simulations and for steady-state power flow analysis. The main contribution lies in the development of a common modeling and c...

Pumped hydro energy storage (PHS) currently is the only electricity grid storage technology with substantial deployment throughout the world, representing over 99% of storage capacity, but other storage technologies such as batteries are increasingly finding application. In Europe, the implementation of storage systems is expected to increase becau...

This paper presents a method to optimize equipment investments in multizonal transmission systems, considering spatial properties of the areas of focus. Together with a probabilistic technique for assessing nodal injection capability, the method in the paper completes the methodology of a long term transmission system planning tool. Transmission to...

The transmission grid in Europe is interconnected to guarantee the security of supply and to facilitate the competition among different market players, thereby making the system highly meshed. It is a challenging task for the transmission system operators (TSOs) to manage the power flows in their system, especially in the light of integration of re...

The future power system is characterized by more renewable and uncontrollable capacity at the supply side and an electrification of energy at the demand side. Both evolutions increase the need for flexibility in the power system. Although this flexibility can be triggered at the supply and demand side, the latter is often overlooked. In this perspe...

Electricity production from centralised and decentralised renewable energy resources in Europe is gaining significance, resulting in operational challenges in the electricity system. Although these challenges add to the locational and time dependency of the underlying cost of operating the system, this variability in time and location is not reflec...

The ability of load to respond to short-term variations in electricity prices plays an increasingly important role in balancing short-term supply and demand, especially during peak periods and in dealing with fluctuations in renewable energy supplies. However, price responsive load has not been included in standard models for defining the optimal s...

The scene of electric power systems has changed drastically and will continue to do so in the years to come. Causes of this evolution are the liberalization of the electricity markets and the increased use of intermittent renewable energy. Uncertainty in the transmitted power and congestion of the lines raise the need for new technologies. High vol...

In this paper, a methodology is presented to optimize the dc voltage droop settings in a multiterminal voltage-source converter high-voltage direct-current system with respect to the ac system stability. Implementing dc voltage droop control enables having multiple converters assisting the system in case of a converter outage. However, the abrupt p...

This paper discusses the extension of electromechanical stability models of voltage source converter high voltage direct current (VSC HVDC) to multi-terminal (MTDC) systems. The paper introduces a control model with a cascaded DC voltage control at every converter that allows a two-terminal VSC HVDC system to cope with converter outages. When exten...

This paper analyzes the influence of the converter droop settings and the dc grid network topology on the power sharing in a dc grid based on voltage source converter high voltage direct current technology. The paper presents an analytical tool to study the effect of the droop control settings on the steady-state voltage deviations and power sharin...

In a DC grid, contingencies such as converter outages give rise to a current imbalance that is reflected in the DC node voltages in the grid. This imbalance has to be accounted for by changing the currents flowing in and out of the DC system. These DC node voltages can be directly influenced by controlling the DC current of the HVDC converter at th...

This paper considers the portfolio management problem of a flexibility aggregator under uncertainty on real-time prices. Solving this stochastic optimal control problem in a reasonable time, considering overall scalability, comfort settings and grid constraints, is a challenging task. This paper tackles these problems by making use of a Three-Step...

The electric power system in Europe is fundamentally changing, due to the liberalization of the energy market, the internationalization of electric power system operations, the shift towards renewable energy sources and the increased difficulty to install new transmission lines. The transmission system operators face new problems and they require n...

The development of two educational workshops, one on energy efficiency and one on human-machine interfaces, is detailed and discussed. Attraction to engineering is not created as much as lost at early ages through current education methods. Through positive, hands-on experiences with engineering in K-12 education, this trend can be turned. IEEE stu...

In this paper, method to identify strong nodes in a transmission grid is shown. The method can be used to identify transmission system investment needs and can serve as filter for transmission system investment optimization. Based on an optimal power flow calculation, the maximum power injection capability of buses is calculated. In this context AC...

The price set in electricity markets is given by the intersection of supply and demand during a given time period. The demand-side has traditionally been a price taker while the supply-side actively adjusts the output of the market clearing unit to fluctuations in consumption. Currently, there is a transition toward active demand participation that...

In a liberalized electricity market, the introduction of dynamic pricing for residential consumers has consequences on the whole network structure. This structure consists out of all market participants and their interactions. To assess the impact of dynamic pricing, an accessible representation of the network structure is implemented in a networke...

In a transmission system with HVDC lines or other power flow controlling devices, it is possible to control the active power flow in the lines and indirectly also in other parts of the system. The active control of the power flow through a grid can affect flow-based transmission cost allocation methods as they are based on the DC load flow model. T...

This contribution studies the impact of wind power on the operation of island power systems. The analysis focuses on the available flexibility of thermal generation to balance wind power variations and prediction errors. This issue is highly relevant for small and medium sized islands where interconnections are absent and the smoothing of variation...

The increasing share of renewable energy sources for electricity, driven by variable output technologies such as wind and solar photovoltaics, is expected to have an impact on the operational reserve requirements of power systems. This study applies a probabilistic approach to estimate reserve requirements and establishes a methodology that makes i...

This paper discusses the aggregated active power control in a Voltage Source Converter High Voltage Direct Current(VSC HVDC) system, interconnecting one offshore wind farm and two asynchronous onshore grids. Existing control strategies have all been developed for point-to-point connections and need a revision when an operation with more than two co...

Energy consumption in buildings represents about one-third of the world-wide energy consumption. Consumers often are not fully aware of energy-conserving measures they could take. Intelligent control of the heating and lighting systems in buildings is one way to increase energy-efficiency. Children and young adults influence domestic energy consump...

This paper presents a methodology to study the impact of different DC voltage droop settings on the AC system stability. When several Voltage Source Converters (VSC) in a DC system jointly control the DC voltage by means of droop control, an outage of one converter results in an abrupt change of the active power set-points of several other converte...

Due to limited predictability of variable renewable energy sources such as wind energy, the balance between demand and supply in electricity systems is challenged. Market players integrating these technologies in their portfolio face increasing imbalances and are, consequently, charged with cost-reflective imbalance tariffs. In this paper, an optim...

With the development of VSC HVDC transmission, the realization of the first VSC MTDC grid is coming within reach. An outstanding issue is DC voltage control in MTDC systems. The easiest way to maintain stable operation is to assign the task of DC voltage regulation to one converter. This paper discusses a control strategy for an extended VSC MTDC g...

Uncertainty on arrival and departure times makes the scheduling of plug-in hybrid electric vehicles an intrinsically stochastic optimization problem. To take the stochastic nature of this problem into consideration, a scalable stochastic optimization strategy has been formulated. Generally, stochastic programming methods are computationally demandi...

A method to determine the optimal transmission system topology for multiple offshore wind farms is introduced using a rule-based generic algorithm. The methodology is implemented as a software tool determining the best economical and technically feasible offshore transmission solution. The optimization algorithm takes radial, ring shaped, and meshe...

The LINEAR project (Local Intelligent Networks and Energy Active Regions) focuses on the introduction and implementation of innovative smart-grid technologies in the Flanders region, and aims at a breakthrough in the further development and deployment of these solutions. It consists of a research component and a large-scale residential pilot, both...

Against the background of more renewable energy, limited investment in power generation, ageing distribution and transmission infrastructure, and the electrification of energy, the demand side of the electricity system is gaining attention. Moreover, the increasing ability to automate household appliances allows to involve the demand side more easi...

This paper discusses the modeling and control of Voltage Source Converter High Voltage Direct Current (VSC HVDC) systems in a multi-terminal configuration (MTDC). Both steady-state interactions, as well as transient stability modeling and control are addressed. Simulation results show that adequately modelling the DC voltage droop characteristics or...

In many papers, in dealing with bifurcation analysis of power systems, the power system is modelled as an ordinary differential equation system, in order to conveniently use the theory and numerical tools developed for bifurcation analysis of ordinary differential equation systems. We explain in this work how state‐of‐the‐art numerical techniques f...

Linear (Local Intelligent Networks and Energy Active Regions) is a large-scale project about smart grids. It is collaboration between industry and research institutes. The Flemish government, as well as the industry, support the project financial with budgets for innovation. The project is carried out by a consortium of around twenty partners and w...

The road towards a single internal electricity market in Europe is hampered by limited cross-border transmission capacity. As investing in new cross-border transmission capacity is a long term process with a lot of challenges, optimal use of the existing capacity is the best short term measure. In Europe, Flow-based Market Coupling (FMC) is the sta...

In this paper, a steady-state multi-terminal voltage source converter high voltage direct current (VSC MTDC) model is introduced. The proposed approach is extended to include multiple AC and DC grids with arbitrary topologies. The DC grids can thereby interconnect arbitrary buses in one or more non-synchronized AC systems. The converter equations a...

Demand response, defined as the ability of load to respond to short-term variations in electricity prices, plays an increasingly important role in balancing short-term supply and demand, especially during peak periods and in dealing with fluctuations in renewable energy supplies. However, demand response has not been included in standard models for...

More and more transmission planning has to cope with a multilateral context due to increased electricity exchanges between zones. Whereas investments are decided upon and approved at the zonal level, policy goals can be formulated at a higher supranational level. The zonal level, however, can have its own objectives or way to reach the policy goals...

In this contribution international experiences concerning the integration of electrified cars (e-cars) into the grid in particular when there is a high penetration of renewable energies are presented. Future shortage of fossil fuels and concerns about security of supply derived the idea of electrified mobility which requires a new approach to desig...

In this paper, we present a new Matlab-based toolbox for power system analysis, called MatDyn. It is open-source software, and available for everyone to download. Its design philosophy is based on the well-known open-source Matlab toolbox MATPOWER, but its focus is transient stability analysis and time-domain simulation of power systems, instead of...

Digital meters for electricity and gas, which are connected to an information infrastructure are an important component of the smart metering and smart grid infrastructure being deployed. Besides technical and business perspectives, such infrastructure has an impact on the consumer and on authorities that have public service obligations. This paper...

In this paper, a power flow model is presented to include a DC voltage droop control or distributed DC slack bus in a Multi-terminal Voltage Source Converter High Voltage Direct Current (VSC MTDC) grid. The available VSC MTDC models are often based on the extension of existing point-to-point connections and use a single DC slack bus that adapts its...

Notwithstanding its variability and limited controllability, wind power is expected to contribute strongly to electricity generation from renewable energy sources in the coming decades. Treating wind power as non-dispatchable by subtracting its output from the original load profile, results in a net load profile, which must be covered by convention...

The augmented importance of using renewable energy sources to produce electricity and their integration with the transmission grid leads to a significant increase in loop flows in the transmission network. The uncertainty of wind energy, one such renewable energy source, and its stochastic nature leads to variable energy and cross border flows thro...

This study identifies potential electricity market design (EMD) approaches of sending Locational Signals (LS) that guide the location of generation plants. The stability, predictability and strength of LS from each approach are evaluated using cases from European electricity market. Additionally, important LS outside EMD are identified and compared...

A new protection algorithm for DC line faults in multi-terminal high voltage DC (MTDC) systems is proposed in this study. A four-terminal MTDC model is used to investigate fault behaviour and detection using the simulation program PSCAD/EMTDC. The simulation results are post-processed using Matlab. The fault clearing must be done very rapidly, to l...

Consumer benefits of dynamic pricing depend on a variety of factors. Consumer characteristics and climatic circumstances widely differ, which forces a regional comparison. This paper presents a general overview of demand response programs and focuses on the short-term benefits of dynamic pricing for an average Flemish residential consumer. It reach...

Planning models have been used for many years to optimize generation investments in electric power systems. More recently, these models have been extended in order to treat demand-side management on an equal footing. This paper stresses the importance of integrating short-term demand response to time-varying prices into those investment models. Thr...

In this paper, two standard VSC HVDC dynamic models are proposed. The full system model, consisting of the converter and its controllers, DC circuit equations, and coupling equations, is derived mathematically. Special attention is given to the filter and phase-locked loop (PLL), often neglected in VSC HVC modelling. A reduced order model is then d...

This article deals with a specific support mechanism exempting offshore wind power generators partially from their balancing responsibilities by means of a tolerance margin. This specific support mechanism was enforced in Belgium as from 2009 and is defended by its proponents in view of the lower power output predictability at offshore locations. A...

The European transmission grid is facing an investment challenge. There is a strong call for more transmission capacity. At the same time, the investment climate is fierce and troubled by public opposition, a complex regulatory framework, etc. Many transmission capacity expansion projects are delayed or canceled. In this paper different technology...

Portfolio theory has found its way in numerous applications for optimizing the electricity generation mix of a particular region. Existing models, however, consider typically a single time period and correspondingly do not properly account for actual dispatch constraints and energy sources with a non-dispatchable, variable output. This paper presen...

The contribution of electric energy in the civilization and modernization process is undeniable. However, the people in rural and remote areas are the ones who can get the benefits from electricity access and economic achievements very late. Rural electrification is an essential element for the development in these areas. It can play an important r...

This paper shows an optimization method to determine the best economically and technically feasible transmission topology for connecting multiple offshore wind farms to the main electricity grid. The proposed optimization algorithm determines the connection possibilities with the lowest life cycle system costs. These possibilities are ranked with t...

This paper presents and motivates the development of a techno-economic education package, consisting oftwo simulation games, to simulate both the trading and the generation of electricity in a liberalized market. Six attributes (storytelling; players as problem solvers and explorers; feedback; challenges that fit the student characteristics; compet...

The European Commission has set a rene-wables target enforcing wind power investments. Simultaneously, a smart meter roll-out, in the context of smart grid developments, is said to facilitate the integration of this variable source of power generation. This paper analyzes to which extent a price responsive demand-side contributes to an efficient sh...

European policy goals are challenging for transmission networks, requiring investments in cross-border capacity. Despite those goals, an increased awareness of the need for investments and the voluntary cooperation among countries sharing the challenges, a regulatory gap between national and European interests persists. Further development of a Eur...

For analyzing and simulating the behavior of multiconductor transmission lines, a measurement of the transmission-line parameters is needed. In this paper, an accurate method for measuring the full capacitance, inductance, resistance, and shunt-resistance matrices by a vector impedance meter is described. The method has been applied for frequencies...

In this paper, the implementation of a sequential AC/DC power flow computation algorithm for Multi-terminal Voltage Source Converter High Voltage Direct Current (VSC MTDC) systems is discussed. The already available models for two-terminal Voltage Source Converter High Voltage Direct Current (VSC HVDC) presented in literature have certain shortcomi...

When feeding an induction motor by a PWM-inverter through long cables, reflections occur and overvoltages may arise. Using a terminator in parallel with the motor, the overvoltages are reduced. An analytical calculation of the motor voltage is obtained using transmission line theory. Simulations and measurements allow to verify the results.

In this paper, a new general voltage source converter high voltage direct current (VSC MTDC) model is derived mathematically. The full system model consists of the converter and its controllers, DC circuit equations, and coupling equations. The main contribution of the new model is its valid for every possible topology of the DC circuit. Practical...

Smart grids rely on a dependable information infrastructure for the monitoring and control applications. Two elements can enhance the suitability of the communication and control infrastructure for such smart grid applications. Overlay networks allow to resiliently deal with nodes that appear and disappear, as well as with the dynamic nature of the...

In this paper, a sequential AC/DC power flow algorithm is proposed to solve networks containing Multi-terminal Voltage Source Converter High Voltage Direct Current (VSC MTDC) systems. In VSC HVDC technology, the converter losses add up to a significant fraction of the overall system losses. However, they are often neglected or not taken into accoun...

Electrical energy storage services can bring benefit to multiple stakeholders in the distribution grid. Energy storage owners maximize their profit on an external energy market. This can cause a conflict with the distribution system operator because a grid is designed in terms of peak power, not energy. The subject of this paper is a optimization m...

This paper evaluates the application of the specific Belgian mechanism to relief offshore wind power generation partially from the imbalance settlement mechanism. A tolerance margin for imbalances originating from offshore production deviations is installed in which producers and balancing responsible parties enjoy beneficial imbalance tariffs. Thi...

Awareness among policy makers that electricity grids need to become smarter is growing. To allow policy makers to design policies for improving the smartness of grids, discussion is needed on what makes an electricity grid smart and how that this smartness can be measured. This paper provides a methodology to measure the smartness of the electricit...

The study presented in this paper determines the optimal location for the Belgian substation of a potential Belgium-UK VSC HVDC connection from stability considerations. Two locations are taken into consideration: Zeebrugge and Eeklo-Noord. This study analyzes the impact of the VSC HVDC connection on the transient stability of the Belgian grid. The...

This article focuses on the design of balancing markets in Europe taking into account an increasing wind power penetration. In several European countries, wind generation is so far not burdened with full balancing responsibility. However, the more wind power penetration, the less bearable for the system not to allocate balancing costs to the respon...

Many recent blackouts might raise a concern on how the introduction of distributed generation (DG) (from renewable or non-renewable energy resources) into the network influences its secure operation in terms of dynamic performance. The anti-islanding criteria of DG may harm the secure operation of the power system. In this paper, the maximum penetr...

Countries in Sub-Saharan Africa (SSA) are faced with the problem of expanding urban growth and demographic shift, necessitating the need to achieve a sustainable rate of positive economic growth. To move toward a sustainable future, many reforms have been implemented, including in the energy sector. Reforms in the energy sector will lead to a secur...

As Europe wants to move towards a secure, sustainable and competitive energy market, it has taken action, amongst other, to support electricity from renewable energy sources (RES-E) and to mitigate CO2 emissions. This paper first qualitatively discusses price- and quantity-based measures for RES-E deployment as well as CO2 mitigation. Next, a simul...

Fast switching of PWM-inverters cause a lot of electromagnetic interference (EMI). To lower the dv/dt, output filters are available. In this paper, the influence of the cable and the output filters on conducted emission is investigated. By combining impedance measurements and EMI-measurements particular dips in the spectrum can be explained.

The transmission of bulk power through HVDC is growing. Expansion of the HVDC network over large distances across the developing countries poses new challenges. The classic HVDC remains a cost effective alternative for such cases. The recent progress in power electronics heralded a new era for the HVDC technology. The VSC HVDC is believed to be a s...

The scene of electric power systems has changed drastically and will continue to do so in the years to come. Causes of this evolution are the liberalization of the electricity markets and the increased use of intermittent renewable energy. Uncertainty in the transmitted power and congestion of the lines raise the need for new technologies. High vol...

Renewable energy sources, and especially wind, take an increasing fraction of the European electric energy generation and they form an important part of the plans of the European commission towards a more sustainable future. Also for Belgium, wind power offers the most important renewable energy potential. Especially offshore wind power projects ar...

In Europe, the auctions organized by "power exchanges" one day ahead of delivery are multi-unit, double-sided, uniformly priced combinatorial auctions. Generators, retailers, large consumers and traders participate at the demand as well as at the supply side, depending or whether they are short or long in electric energy. Because generators face no...

The amount of distributed energy resources (DER) in the grid is continually increasing, and the potential benefits and drawbacks are becoming clearer. However, there is still a lack of clarity in how these multiple effects interact and which trade-offs should be made in the integration of new DER. There is a clear need for appropriate DER planning...