Integration of Innovative Distributed Sensors and Actuators in Smart Grids

The project deals with the individual technology development and the integration of these novel components with future-proof and secure automation architecture and protocols. Integration of existing components such as smart meters and other sensors is also part of the research.

1. Develop innovative Sensors and Actuators for the customer and distribution grid domain
2. Integrate these with future-proof automation architecture and protocols
3. Perform Cost-Benefit Analysis for selected grid integration approaches with and without iniGrid technology
4. Ensure flagship character by interlinked field trials in customer and grid operation domain.

Goal 1:

Develop innovative sensors and actuators for the customer and distribution grid domain

The key innovative approach of iniGrid is the integration of the power management function and the grid protection function within one device, called the Smart Breaker. The consolidation of these two function-layers is reasonable both from a technical and a cost perspective. These innovative switching devices are located at the energy customer domain (mostly commercial customers) to provide:

a) protection functions for downstream system components (e.g., power consumers, installation facilities, etc.) or humans in the case of a fault, comparable to known devices like circuit breakers;

b) power management by intentionally switching ON and OFF related power branches; and

c) data on system state by additional sensor-based data to proactively indicate possible future faults on the grid, thus increasing the overall power availability (reliability).

In order to provide this feature-set, a circuit breaker (protection function) needs to be upgraded with dedicated communication interfaces that are suitable for remotely executing commands that are generated by a control unit, in response to special system conditions. 

The second innovative approach of iniGrid is the development of a medium voltage sensor. In a significant number of medium voltage switchgear and structures, voltage sensors for air insulated equipment are needed. Here accurate and stable voltage sensors have to be integrated into post insulators or other insulating structures. 

iniGrid aims to reach the required accuracy of at least class 0.5 according to IEC 61869 although these isolators have no earthed cover and therefore suffer from parasitic capacitances to geometrically and electrically (switching state) undefined external structures. It is therefore necessary to develop sensor structures, which overcome these problems by innovative electrode structures and materials, which suppress the impact of the parasitic capacitances to below the accuracy class requirements, while still fulfilling the strict partial discharge requirements of IEC61869. This task shall be investigated theoretically and experimentally, fully functional prototypes shall be developed and applied in this project.

Goal 2:

Integrate the sensors with future-proof automation architecture and protocols

To setup a local power management system and support active grid operation based on a Smart Beakers, these devices need to be network-enabled so they can send data to a remote node and to receive and process incoming data from a remote node. Depending on the system status a specified device can be switched off and on to follow a dedicated power policy (e.g., load shedding).

The local communication technology between multiple devices within a single installation (about 5 … 50 devices) could be realized either wire- or RF-based technology. Smart Breakers will firstly be integrated in control and energy management systems for the energy customer domain, together with smart meters and other local data sources. However, they also provide valuable information about the power system state, in a similar way as the developed MV sensors on MV level. This can be more detailed information as available from smart meters, and includes the actuator function. Therefore, it must be possible that selected data points from Smart Breakers can be made available for the external market and grid control systems.

This poses questions of communication media, protocols, security and also privacy for this application. Covering the customer and distribution domain up to the secondary substation, these questions shall be covered in iniGrid. 

Goal 3:

Perform cost benefit analysis for selected grid integration approaches with and without iniGrid technology

While it has become eminent that conventional grid reinforcement is often a costly approach, smart grid solutions enabling active management of renewable generators can be seen as the solution of choice for certain grid areas (also depending on the depreciation status of several grid assets). However, currently state of the art smart grid technologies comprising of industrial controllers, automation equipment and specialized hardware comes with a price. This reduces the application spectrum of smart grid technology and is a barrier for economy of scale effects.

Goal 4:

Ensure flagship character by interlinked field trials in customer and grid operation domain.

The developed smart LV breaker and MV sensor components will be tested in a realistic environment, where the automation architecture and procedures for large scale distributed installations is performed. Here, unexpected issues that cannot be tested in lab validation will be found. The successful system operation is demonstrated at distributed test sites at Linz Strom (Linz), AIT (Vienna), FH OÖ (Wels) and Ars Electronica Center.

With this, different target groups (network operators, industry, students, scientists and especially the general public by the activities of the Ars Electronica Center) can be reached.