New Era of Low-Voltage Grid Management – LV SCADA

Supervisory Control and Data Acquisition (SCADA) systems are pivotal for the operational management of electrical grids as they allow for remote monitoring, data acquisition, and control of various processes. Though traditionally deployed at the medium and high voltage levels, there is a paradigm shift towards implementing SCADA systems in low voltage (LV) grids.

The rising demand for low voltage grid SCADA solutions

Historically, LV grids were operated with a lesser focus on real-time data monitoring and analytics, mainly due to their relatively straightforward and predictable load patterns. However, the transition to a more decentralized energy landscape and the race to reduce the global CO2 footprint led to a number of new challenges in managing LV grids.

On one hand, the increasingly decentralized feed-in and on the other hand, the higher penetration of loads such as charging stations and heat pumps lead to increased strain on the low-voltage networks. This increases the risk of faults and disturbances, whether due to overloads in the grid or activated circuit breakers.

Moreover, the increasing complexity and dynamics in the power grids require a more active network operation, which is characterized, for example, by more frequent switching or potentially, even control interventions.

The conventional approach to grid operation, characterized by manual interventions and lack of exhaustive or real-time granular monitoring, reaches its limits here. To meet the dynamic requirements of modern energy systems, more precise monitoring and fundamentally higher transparency of the grid state are required.

It also requires agile and more responsive systems to detect and fix problems and errors early. At the same time, many established operational processes from the high and medium voltage must be rethought and adapted to the large volumes of data and mass processes in the low voltage. Taken together, these trends drive the demand for a new category of support systems: SCADA for low voltage.

Hardware components of a low voltage SCADA system

At the core of a SCADA system for power grids are several critical hardware and software components. Traditionally, the essential hardware components include sensors and actuators placed throughout the grid for data collection and execution of control commands, respectively, and Remote Terminal Units (RTUs) that serve as the interface between field devices and the central SCADA system.

In the case of a low-voltage SCADA system in particular, the role of smart meters extends its significance beyond the traditional one. Smart meters collect detailed energy usage data at short intervals from consumers. This data provides valuable insights into the consumption patterns, peak demand periods, and potential areas for energy efficiency improvements.

So, when integrated into low-voltage SCADA systems, smart meter data enhances the capabilities of the SCADA system. It contributes to improved visibility of the low-voltage grid, facilitates introduction of flexibility management (aka load control) , and helps in quicker identification and localization of faults within the LV grid.

In addition to smart meters, supplementary hardware will be required for the execution of control commands at the low-voltage level to adjust energy consumption or feed-in according to the specifications of the SCADA. In this context, smart meter gateways and control boxes, even if they do not directly belong to the hardware components of the SCADA system, play an important role. They enable communication and control of feed-ins and loads and thus support the SCADA in optimizing energy flow during peak times

Software components of a LV grid SCADA

A more detailed monitoring of the grid state as a better basis for decision-making in operation management requires that more data points must be collected, processed, and analyzed. Only in this way can advanced functionalities such as grid state estimation or congestion management be implemented and bottlenecks quickly identified and remedied. The available data includes not only a wide range of grid data such as transformer or feeder measurements but also high-resolution grid state data from the smart meters

All this poses entirely new requirements for software systems than for a conventional SCADA system. It requires more integration points that are flexible, and a scalable, high-performance IT architecture.

The ability to efficiently manage mass data is becoming increasingly important as the amount of data collected from various sources of the energy network steadily increases. With increasing penetration of smart meters, millions of data points can quickly accumulate. A low-voltage control system must be able to filter the essential information from these large amounts of data and make it available to the user. This requires scalable and efficient data processing and analysis methods.

It is also important to consider that complete or correct data is not always available. In this context, the ability to work with poor data quality or low penetration of measurement data is also critical. A good LV SCADA must therefore have algorithms that offer reliable analysis and forecasting capabilities even under this uncertainty.

Moreover, a low-voltage SCADA system must offer a high degree of automation. The LV area includes considerably more grids and assets than the medium or high voltage area. Monitoring and control based on traditional, largely manual methods cannot be managed with the available personnel resources.

Automated systems and processes are therefore crucial to ensuring the efficiency and reliability of grid monitoring and control. This automation not only helps manage the complexity and scope of the required monitoring but also enables a faster response to changes in the grid.

The significance of low voltage SCADA systems in the modern energy landscape

So, what is the driving force behind the rising need for SCADA systems at the low voltage level?

The increasing integration of decentralized energy resources (DERs) such as photovoltaics and storage, as well as the electrification of the heating and mobility sectors (think heat pumps and charging stations), increases the dynamics in the power grid and leads to greater strain on the operational resources. This results in an increased risk of grid instabilities and failures.

These factors require more sophisticated grid management and monitoring capabilities to ensure stability and optimize energy flows.

However, we need to redefine the concept of a control system if we want to apply it in the context of low-voltage because traditional SCADA systems used in higher voltage levels cannot meet the specific requirements of LV networks – especially in terms of mass data handling and the need for high levels of automation.

Therefore, new and innovative solutions are needed that are specifically designed for the requirements of low-voltage grid to ensure efficient data processing and automated decision-making. Only in this way can the reliability and performance of modern power grids be ensured.