Daniel Esteban Morales Bondy

Electric vehicle charge planning using Economic Model Predictive Control

Economic Model Predictive Control (MPC) is very well suited for controlling smart energy systems since electricity price and demand forecasts are easily integrated in the controller. Electric vehicles (EVs) are expected to play a large role in the future Smart Grid. They are expected to provide grid services, both for peak reduction and for ancillary services, by absorbing short term variations in the electricity production. In this paper the Economic MPC minimizes the cost of electricity consumption for a single EV. Simulations show savings of 50-60% of the electricity costs compared to uncontrolled charging from load shifting based on driving pattern predictions. The future energy system in Denmark will most likely be based on renewable energy sources e.g. wind and solar power. These green energy sources introduce stochastic fluctuations in the electricity production. Therefore, energy should be consumed as soon as it is produced to avoid the need for energy storage as this is expensive, limited and introduces efficiency losses. The Economic MPC for EVs described in this paper may contribute to facilitating transition to a fossil free energy system.

A clearinghouse concept for distribution-level flexibility services

Flexibility resources on the demand side are anticipated to become a valuable asset for balancing renewable energy fluctuation as well as for reducing investment needs in distribution grids. To harvest this flexibility for distribution grids, flexibility services need to be defined that can be integrated with distribution grid operation and that provide a benefit that can be traded off against other grid investments. Two key challenges are here that the identification of useful services is still ongoing and that the transaction cost for the individually small contributions from the demand side could be prohibitive. This paper introduces a flexibility clearinghouse (FLECH) concept and isolates FLECH key functionality: to facilitate flexibility services in distribution grids by streamlining the relevant business interactions while keeping technical specifications open.

Assessment of distribution grid voltage control strategies in view of deployment

Increasing integration of distributed energy resources (DER) and available monitoring devices in the power distribution grid make system services provided by DERs possible and an integral part of distribution grid operation. Numerous publications have proposed various control solutions by utilizing different capabilities of DERs and regulating devices to assist grid operation. However, very few of them have discussed the opportunities and barriers of deploying the control strategies in practice. This paper reviews some typical control solutions on providing voltage control services. Furthermore, it provides some qualitative discussions on the challenges in view of deployment. Several qualifying metrics are listed to specify the challenges from different perspectives. A metrics comparison diagram is proposed to asses deployment of a control strategy. Five case studies are presented to identify the corresponding advantages and challenges of deployment.

Procedure for validation of aggregators providing demand response

As aggregators become viable sources of ancillary services, they will be required to undergo a validation process similar to the prequalification process of traditional generators. Aggregators are fundamentally different from traditional generators in that they are formed of a large quantity of small heterogeneous resources that are geographically distributed. Therefore, a new test procedure must be designed for the aggregator validation. This work proposes such a procedure and exemplifies is with a study case. The validation of aggregators is essential if aggregators are to be integrated succesfully into the power system.

Design of experiments aided holistic testing of cyber-physical energy systems

The complex and often safety-critical nature of cyber-physical energy systems makes validation a key challenge in facilitating the energy transition, especially when it comes to the testing on system level. Reliable and reproducible validation experiments can be guided by the concept of design of experiments, which is, however, so far not fully adopted by researchers. This paper suggests a structured guideline for design of experiments application within the holistic testing procedure suggested by the European ERIGrid project. In this paper, a general workflow as well as a practical example are provided with the aim to give domain experts a basic understanding of design of experiments compliant testing.

A functional reference architecture for aggregators

Aggregators are considered to be a key enabling technology for harvesting power system services from distributed energy resources (DER). As a precondition for more widespread use of aggregators in power systems, methods for comparing and validating aggregator designs must be established. This paper proposes a functional reference architecture for aggregators to address this requirement.

Performance requirements modeling and assessment for active power ancillary services

New sources of ancillary services are expected in the power system. For large and conventional generation units the dynamic response is well understood and detailed individual measurement is feasible, which factors in to the straightforward performance requirements applied today. For secure power system operation, a reliable service delivery is required, yet it may not be appropriate to apply conventional performance requirements to new technologies and methods. The service performance requirements and assessment methods therefore need to be generalized and standardized in order to include future ancillary service sources. This paper develops a modeling method for ancillary services performance requirements, including performance and verification indices. The use of the modeling method and the indices is exemplified in two case studies.