Demonstration of

coordinated ancillary services covering different voltage levels and the integration in future markets


Innovation Cell Austria

IC Austria is focusing on coordinated voltage control based on existing research infrastructure within the distribution grid area of Salzburg Netz, which includes medium voltage as well as low voltage networks. Besides Salzburg Netz, the IC partners include Siemens, AIT and TU-Vienna. This IC enhances concepts and results of the prior project ZUQDE and the ongoing project LEAFS. Whilst LEAFS focus on LV operation considering decentralized storage, within DeCAS this it is aimed for integrating this aspect via iSSN. As one of the enhancements an intelligent substation (MV/LV Interface) will be connected to the SCADA system to control the reactive power flow over system boundaries. 

Technical Requirements

The figure below shows the target schematics of IC Austria mapped to SGAM. The aim of this specific Innovation Cell is to establish a coordinated VAr-control (Volt-ampere reactive) between high, medium and low voltage grids taking augmented concepts for LV grid operation into consideration.

Traditional network operation, still dominant today, is based on three distinct and in terms of control separated levels: the HV transmission network with voltage and frequency control, the MV distribution network with basic voltage control and the LV distribution network, without observability and controllability. This topology is reflected also in most smart grid pilot projects, focusing on the three levels separately. However, with the rising share of DG the influence between the levels will become substantial, and will require addressing the interaction between HV, MV and LV networks. The coordinated network control will form the basis for the definition of new ancillary and market services, and will be tested via simulations and validated on-field. A coordinated approach is essential to analyse the interdependencies across voltage levels to guarantee overall system stability with increased hosting capacity at LV and MV level. As field trial region, the northern part of the federal state of Salzburg was chosen. This part of the grid is also modelled in an additional, project specific SCADA system. Also the intelligent substation network (iSSN) Köstendorf is included in the field trial area. Therefore it will be possible to demonstrate the interface and the interaction of the central SCADA System with a decentralized intelligent local grid.  

Stakeholder Adoption

The implementation of a smart grid will impact different stakeholders such as customers (prosumers), network operators, aggregators and market actors. In future the classic consumer will be substituted by prosumers which are operating DG, flexible loads like e-cars and battery storage systems. Via demonstration activities and description of best practices the DeCAS project will reduce the barriers for engaging the prosumers, as well as technicians and other staff at DSOs in smart grid topics and how to take part in future ancillary service provision. Therefore one part of the planned project will evaluate promising concepts for low voltage grid operation e.g. transferred from the world of IoT (Internet of Things), bringing the stakeholders together. The figure below shows some exemplary use cases for IoT based operation of iSSNs as well as how they could interface with MV/HV SCADA DMS as described above.

In this project, a true interaction between the decentralized controllers (=iSSN) on the LV/MV side and the substation on the MV/HV side will be designed and implemented in a proof-of-concept/field test. To avoid flooding of the control center, the iSSNs aggregate and process the collected data from prosumer’s technical representatives (e.g. a Customer Energy Management System) and provide KPIs. If necessary, more detailed information can be requested by network operators or planers. A further important advantage gained by using IoT for the iSSN is that local information can be provided directly to service teams.  

Market Requirements

Future distribution grids will include a range of flexibilities, but these are often not owned by DSOs, but rather by prosumers or independent plant operators. Inter-voltage-level ancillary services contracted bilaterally or via flexibility markets could create an incentive for aggregators and prosumers to offer their flexibility also to DSOs or attract DSOs to act as platform operator. However, markets are not in the scope of the developments around the IC Austria.