Siemens Energy delivers substation of the future

As the largest distribution system operator in Baden-Württemberg, Netze BW wanted to design a substation with ecological, yet economically sustainable components. With the previous delivery of a CO2-neutral circuit-breaker for a substation in Nördlingen, Siemens Energy had already proven its competence in environmentally friendly products. Combined with a future-oriented vision of a digitally enabled substation, Siemens Energy convinced Netze BW to implement a complete digital substation in Burladingen; where switchgear becomes Sensgear® and a transformer becomes a Sensformer®.

To meet the customer's requirements, the latest innovations from Siemens Energy were chosen. This includes the world's first SF₆-free gas-insulated switchgear (GIS) with a rated voltage of 145 kV. As part of Siemens Energy’ Blue portfolio, the GIS is insulated with clean air. On top of providing the best properties as an arc extinguishing medium, clean air technology represents a climate-neutral solution, with Zero additional expenses of mandatory handling, recycling, and reporting in the EU that would be required for the application of SF₆. Vacuum interrupter technology also offers ‘sealed for life’ technology, by virtually Zero maintenance.

Another innovation is the usage of low-power instrument transformers (LPIT) to measure current and voltage within the GIS. This innovation relies on the application of a Rogowski Coil for the measurement of the current and an electrical field probe with capacitive principle for voltage measurements. They are used in the conventional bushings between the gas compartment of the GIS, offering the most compact way to accurately and safely measure current and voltage and to transmit data digitally. A network cable transmits the analogue signals from the sensors through a connectivity box to the merging unit, which converts the measurements into digital signals for real-time evaluation.

As well as Sensgear, the substation will include two 40 MVA Sensformer. Both Sensgear and Sensformer are enabled with Siemens Energy’ digital intelligence and cloud-based technology. This intelligence analyzes and provides feedback about asset parameters, captured by sensors, into the cloud. Sensformer can therefore be load-optimized thanks to this real-time data.

Based on 40 years of experience manufacturing medium-voltage vacuum interrupters, with more than 5.5 million tubes delivered, Siemens Energy introduced proven vacuum interrupter technology into high-voltage grids of up to 145 kV. Netze BW continues to rely on environmentally friendly products with this technology. Siemens Energy Blue portfolio requires no SF₆ switching and insulating gas. This innovative solution relies on a vacuum interrupter unit for switching and extinguishing the arc and on Clean Air for insulation. Clean Air is technically prepared and purified air in a mixing ratio of 80 percent nitrogen to 20 percent oxygen. Siemens Energy former Siemens has been using this technology in the medium voltage range up to 72.5 kV for over 40 years. Switchgear, as part of the Blue portfolio, is available for voltage ranges of up to 145 kV, offering the same performance, as well as additional, superior features. One result of risk-free handling is that certain precautions are no longer necessary during shipping, installation, maintenance, and recycling. Nor is there any requirement to report the quantity of gas applied in the devices as it is mandatory for SF₆ according to the EU-F-Gas-regulation.

Siemens Energy’ grid solutions enabled as Sensformer® and Sensgear®, allow grid operators to more effectively manage their network. With an eye to the grid anywhere, at any time, customers can get an overview of their asset’s main functionalities such as temperature, oil-level and winding current, enabling more informed operational decisions. With SF₆ insulated switchgear, future annual reports can be generated from the cloud. In the long-term, this can facilitate a more economic and efficient tackling of challenges, such as integrating the growing share of renewables and distributed energy into the power grid. The ability to store and process operational data, allows customers to harness the wealth of generated data through value-adding applications and advanced analytics, enabling a more cost-effective operation. Parallel to the project, Siemens and Netze BW are working with the big data in order to analyze how the collected data can be further utilized with analyses and software applications.

Through the production of innovative SF₆-free equipment Siemens Energy is supporting the implementation of the United Nations Sustainable Development Goals number 7,9 and 15: “Securing access to affordable, reliable, sustainable and modern energy for all”, “Building resilient infrastructure, promoting inclusive and sustainable industrialization and supporting innovation" and "Living on land".

Transmission products play a vital role in the energy value chain. Siemens Energy Transmission offers all key elements including power transformers, gas-insulated and / or air-insulated switchgear and components, individually or bundled, with related engineering. With our global factory network and leading innovations we provide the highest level of quality and reliability to support our customers in achieving their objectives.