iniGrid
Integration of Innovative Distributed Sensors and Actuators in Smart Grids

Smart Breaker

Figure 1: 3D-Model of the Smart Breaker

Figure 2: Short circuit interruption process

The first key innovative approach of iniGrid is the integration of power management and grid protection functions within one device, called the Smart Breaker.

Hybrid architecture
 • Simulation & test verification (10 kA)
 • Stepwise integration of sub-systems
 • Basic verification with Demonstrator-1
 • Further improvements with Demonstrator-2
 • IGBT-evaluation by TSEP method
 • Packaging on dye-level Power Electronic Module
 • Power Module-1 & -2 (10 kA& 20 kA)

Superfast bypass relay
 • Concept verified by simulation & testing( < 200 μs).
 • Relay-1 & -2 (45 A / 125 A)

Fault current detection algorithm

 • Verified by simulation & testing

Communication
 • Bi-directional RF communication

Medium Voltage Sensor

Figure 3: Testing of the Medium Voltage Sensor

The second innovation is an air-insulated medium voltage sensor, which can be integrated into insulating structures. The challenge here is to provide precise data since these isolators have no earthed cover and therefore suffer from parasitic capacitances to geometrically and electrically (switching state) undefined external structures.

Main parameters
 • Insulation level: 10kV (20kV if required)
 • Accuracy Class 0.5 acc. IEC 61869-9
 • Deviation error: ± 0,5%
 • Phase error: ± 20‘

Influence of fringing earth capacitance
 • Different arrangements of high-voltage electrodes and earth electrodes
 • Significant impact of fringing earth capacitance on phase error
 • Impact on deviation error is negligible

Architecture security recommendations

The following scheme gives an overview about the recommended system architecture based on IEC 62351-10.

Figure 4: Architecture security recommendations

Risk analysis

Figure 5: Flowchart risk analysis

  • Risk analysis was done in the KIRAS project SG2 together Linz AG
  • No significant changes to earlier risk analysis
  • CEMS can be considered critical as it is under control of the operator
  • Impact of depends on number of effected devices
  • Most attacks only have local impact

Rollout-concept

Figure 6: Rollout-concept configuration

Customer energy management system

Figure 7: Graphic interface of the customer energy management system

  • OpenMUC Framework drivers
  • EATON SmartBreaker interfaces
  • GUI and future designs
  • SCADA DSO/aggregator simulator
  • Secure IEC 61850 VHP ready
  • Future critical Q(U) settings
  • Working prototype demo boards
  • Programmable current sink loads HIL emulation
  • Sub smart meter integration in AIT SmartEST lab

Implemented Scenarios

  • Fail safe: limits for Smart Breakers ahead of communication loss
  • Priority list: configuring importance of switched loads for soft start after shutdown or pre-blackout critical emergency states
  • Self consumption: optimizing usage of local renewable generation and battery storage systems

Local domestic smart grid demonstrator

Figure 8: Assessment of models and hardware

Cost-benefit analysis

Use case A

Goal: Automation enabling electricity savings at e.g. industry customers (7x Smart Breaker, 2x R-Pi solution)

Figure 9: Cost-benefit analysis, use case A

Use case C

Goal: Calculation of possible cost savings implementing newly developed Sprecher IT solution as well as MV-sensors in DG DemoNet MV Grids (16 MV Zelisko sensors, 11 Sprecher IT solutions)

Figure 10: Cost-benefit analysis, use case C