Medium-Voltage Connection – WAGO and Ingenieurbüro Pfeffer
15 January 2025
They may not be eye-catching, but customer substations are essential. Any electrical customer with high energy demands – whether a shopping center or a manufacturing facility – is directly connected to the medium-voltage grid of the distribution network operator through a customer substation.
Growing Requirements
Over the years, the demands on these projects have increased. Simply supplying electricity is no longer sufficient. Today, surplus energy from renewable sources must be fed into the grid, heat pumps need to be integrated and charging infrastructure for electric vehicles must be accommodated. Managing these requirements effectively necessitates the continuous recording and processing of measurement data – ensuring seamless communication with the network operator’s control system. Achieving this level of control is only possible with advanced software operating in the background.
Standards-Compliant Customer Substations
Marco Genehr of Ingenieurbüro Pfeffer explains their work: “Our daily task is to design substations and customer substations that fully comply with current standards.” This is no small challenge. The specialists at Rödermark design and plan customer substations (KÜS) of all sizes, from compact to large-scale installations. The general requirements for customer substations are outlined in the VDE-AR-N 4110 technical connection rules. These are further supplemented by individual Technical Connection Conditions (TCCs) set by grid operators. With nearly 900 network operators across Germany, these TCCs can range from 20 to 150 pages, detailing the specific technical requirements for customer substations.
“Comparable to Planning a House”
Marco Genehr tackles these complex projects with extensive experience and a structured approach. “It's similar to planning a house. At its core, someone just wants a place to live. Our customers simply need a KÜS. The decision, as to whether this becomes, figuratively, a normal house or a smart home, is based on individual needs, requirements and possibilities.” For example, how much power do the existing or planned machines need? Do renewable energy generation plants need to be integrated? How many low-voltage rings are required? The substation is then precisely tailored to meet these needs. Throughout the development process, Genehr ensures strict compliance with the supplier’s TCC. If necessary, WAGO is involved from the outset, as every telecontrol-enabled KÜS incorporates WAGO telecontrol and automation components. “Specialized expertise becomes critical, especially during commissioning,” he adds.
Stations in Transition: Increasing Demands
Ingenieurbüro Pfeffer and WAGO have been combining their expertise for over a decade to achieve optimal results. Their first joint project, a glass-encased substation, was a highlight of the 2014 E-World energy trade show in Essen. Since then, project requirements have evolved dramatically. Marco Genehr compares the shift to the transition from slide rules to modern computers. “Ten years ago, substations operated at the level of a slide rule – today, they are at a PC level.” As technology advances, systems grow more complex and content-heavy, making project planning increasingly time-intensive. “To streamline this process, control tasks must be clearly defined from the outset, ensuring they meet both current and future operational needs.” The more precisely these specifications are formulated, the better. “Exact performance specifications accelerate the planning process.” says Genehr. Buffer capacity is built in for future expansion. “Good planning always keeps costs in check – substations must not be overdesigned.” Once the design is finalized, technical documentation is compiled, detailing essential elements such as transformer specifications and protection systems.
The first joint project was a glass substation for the 2014 E-World trade fair in Essen. Photo: Ingenieurbüro Pfeffer
WAGO Supplies Hardware and Software
WAGO provides both telecontrol hardware and the software necessary for seamless communication with network operators. The WAGO Application Customer Substation enables direct access to the energy provider’s control center. The foundation of this system is a standardized telecontrol interface for each customer substation, pre-configured for diverse network applications. As an out-of-the-box solution, it prioritizes ease of use, integrating essential communication protocols and robust cybersecurity features. “The KÜS is configured through parameterization via WAGO Application Customer Substation's intuitive visual interface. This is as simple as it is effective. No programming skills are required, but a basic understanding of telecontrol technology is necessary. You need to know which parameters need to be set,” explains Genehr. He highlights a pressing issue: the shortage of skilled labor, particularly in power engineering and station technology.
Simulating Network Configurations and Future Changes
Ingenieurbüro Pfeffer is also preparing for the future. In collaboration with the Darmstadt University of Applied Sciences, the Smart Grid Lab Hessen is researching the impact of evolving energy flows. “Network configurations and changes can be simulated in the lab.” Genehr explains. Load curves are extrapolated and energy flows are modeled under various conditions. The goal is to anticipate and optimize grid expansion in alignment with the energy transition over the coming decades. “Especially in local networks, technology must be optimized.” WAGO and Ingenieurbüro Pfeffer continue to refine the planning and execution of customer substations, offering their expertise, support, and service – even after commissioning.
From e-mobility and renewable energy to storage systems, smart grids, and cybersecurity, WAGO’s Energy Tech Talk vodcast features expert discussions on the latest developments in the energy sector. Hosted by WAGO industry specialist Heiko Tautor, each episode delivers concise, technical insights. Listen and see now!
Power plant controllers help power plants achieve grid-compatible feed-in management at the grid connection point (GCP). WAGO Power Plant Control allows plant operators and system integrators to meet the requirements for these controllers that are set on the grid side – flexibly and reliably. The solution is certified per VDE-AR-N 4110 and 4120.
