The SENDER project aims to upgrade home automation and energy services and shows how functional testing continues to be an important aspect of these developments.
SENDER is a project funded by the European Commission’s Horizon 2020 program aimed at developing next-generation energy service applications for demand response (DR) and home automation. This is a collaborative project that brings together several organizations such as companies, cooperatives, associations and universities, with Smart Innovation Norway serving as the project coordinator. A key aspect of SENDER is functional testing to ensure that the developed solution meets its objectives and provides a high-quality user experience.
SENDER validation framework
Functional testing verifies that the application works as intended. This ensures that the generated software meets your requirements and works well in a variety of scenarios. This is essential to ensure that energy service applications provide users with the expected services and benefits.
Functional testing ensures that the developed service can handle different scenarios and continues to work reliably over a long period of time. Functional testing also contributes to delivering reliable and user-friendly products. When your application works as intended, users are more likely to have a positive experience. This is especially important for consumer projects like SENDER, which target home automation and DR.
A dedicated verification environment has been developed for functional testing on SENDER. This enabled the deployment of different scenarios to test the system’s response to different DR instructions. Integrate all the necessary components based on the selected test case and connect the SENDER solution with hardware prototypes and simulation tools to emulate the external environment.
The global solution’s decision-making layer, when DR orders from utilities are received and routed to the SENDER solution, was created in partnership with SENDER technology vendors. This enabled laboratory-scale testing and validation of the SENDER solution and related components using a controller hardware-in-the-loop approach using simulated demand outage signals generated by the validation environment.
The tests were designed and executed to provide comprehensive functional coverage and to analyze the dependencies of the developed solution.
The validation environment was deployed utilizing a dedicated shared working environment for system integration and testing called VLab Central, developed, hosted and maintained by AIT Austrian Institute of Technology.
VLab Central provides a virtualized work environment and enables the deployment of containerized services that can be accessed remotely over a local network (LAN) or via a virtual private network (VPN).
During the design of the SENDER system, the importance of providing an external interface to the aggregator was recognized. Since aggregators are the main market actors for SENDER solutions, this interface must rely on well-established and generally accepted standards and protocols for DR schemes.
For the purposes of the SENDER solution, the OpenADR 2.0b specification is recognized as an open communications standard used in the energy industry to facilitate the exchange of information and signals between utilities and end users for DR purposes.
The OpenADR framework has two major components that work together to enable an effective DR program.
- The Virtual Top Node (VTN) serves as the central management system within the OpenADR architecture. It acts as an interface between the utility or aggregator and the participating customers. The VTN is responsible for sending signals to and receiving information from assets. It conveys information such as price signals, grid status, and DR event notifications.
- A virtual end node (VEN) represents an individual asset within a customer’s premises that can respond to DR signals. These include smart thermostats, energy management systems, building automation systems, and even individual home appliances. The VEN receives and interprets signals from the VTN and takes appropriate actions to adjust energy consumption based on predefined response strategies set by the customer or device owner. In other words, the VTN acts as a central command center, sending signals and coordinating responses. Meanwhile, VEN receives these signals and takes the necessary actions to optimize energy usage and participate in the DR program.
Functional testing requires a verification environment that simulates the external systems or components with which the test system must interact. The specific case of SENDER involves testing his OpenADR-based communication and data flow of the SENDER solution using various external configurations.
Functional testing on SENDER also covered different operating modes of OpenADR for exchanging data between VTN and VEN, and had to cover a wide range of deployment options.
The SENDER validation framework, with VLab Central at its core, allows you to integrate all the necessary components according to both the OpenADR specification and the SENDER solution architecture.
Application example: Electric vehicle charging energy management system (EVC-EMS)
Electric vehicles (EVs) are valuable flexible loads for DR programs because their effective charging time is typically less than the time they are plugged in.
For example, auxiliary system services can utilize EVs to support grid operations by changing charging profiles, such as synchronizing EV charging to periods of renewable power output. Additionally, EV owners with dynamic pricing contracts may choose to reduce their power bills by adjusting their vehicle’s charging during periods of power shortages.
A key component of the SENDER solution is therefore the Electric Vehicle Charging Energy Management System (EVC-EMS) developed by Triariog SAS.
EVC-EMS extracts EV-based flexibility from local charging stations, adjusts EV charging prices, calculates available demand flexibility, and notifies external aggregators to dispatch flexible dispatch on demand. This is a system for moving forward.
EVC-EMS is designed for “fast DR” scenarios, i.e., DR use cases where the expected application of DR signals is immediate or near-instant.
While standard peak-shaving DR systems require lead times of hours or days, this setup is designed to provide load balancing and frequency stabilization (such as ancillary and regulatory services) in seconds or minutes. Masu.
For functional testing of EVC-EMS, test scenarios were developed that focused on leveraging the flexibility of EV charging stations to manage voltages in low-voltage (LV) distribution networks.
In this scenario, an external aggregator monitors the power grid to keep voltage levels within certain limits. To generate a DR event, the aggregator can match the network status information with the flexibility prediction obtained from her EVC-EMS. Every 15 minutes, a new set point for the total power consumption of all charging stations is calculated and distributed to the EVC-EMS. The latter acts based on these events and controls the charging station accordingly.
As in a real setup, EVC-EMS is deployed using Trialog’s IT/OT infrastructure. The interface to the external aggregator is a dedicated VEN client that can receive DR signals and send reports to the aggregator’s VTN. REST APIs provide predictive flexibility to aggregators.
The SENDER verification environment is used to emulate and connect all necessary components of external systems in real time. A series of simulators for EVs and EV supply equipment emulates EV charging at local charging stations. Similar to charging stations in a real setup, these simulators communicate with EVC-EMS via Open Charge Point Protocol (OCPP).
The operating state of the LV distribution network is calculated on demand using a power system simulator. The emulated aggregator performs the calculation of the charging station’s total power consumption set point based on the flexibility prediction and the simulated network conditions. The corresponding DR signal is sent to the EVC-EMS every 15 minutes via the VTN server.
The results demonstrate that EV charging coordination utilizing EVC-EMS can be successfully utilized in fast DR programs for voltage control in LV distribution networks. The tested DR scheme was able to significantly reduce the overvoltage, as shown by the comparison of the voltage profiles of unregulated EV charging and EV charging regulated by EVC-EMS.
The SENDER project relies on a dedicated verification environment for functional testing.
Although functional testing is not a new idea, its importance in the product lifecycle is often overlooked. In the energy sector, this seems particularly true for home automation and related flexibility services that take place ‘behind the meter’ and outside the regulated electricity grid.
However, potential issues that are not resolved during testing can cause interruptions or failures in the actual production environment, causing inconvenience to users and potential financial losses.
The SENDER project relies on a dedicated verification environment for functional testing. This validation environment is equipped with the tools and resources necessary to emulate real-world scenarios and thoroughly test the functionality of your SENDER solution. This allows project teams to identify and address potential issues before deploying the solution into production, ensuring a smooth and seamless experience for end users.
Next year, the SENDER solution will be rolled out at three pilot sites in Austria, Finland and Spain. Based on the experience gained during the functional testing phase, the project team is confident that the SENDER solution can be successfully integrated and demonstrate its applicability to the next generation of his DR schemes.
The SENDER project receives funding from the European Union’s Horizon 2020 Research and Innovation program under a grant agreement.
This article will also be published in issue 16 of the quarterly magazine.