IIC Journal of Innovation 5th Edition | Page 40

Outcomes , Insights , and Best Practices from IIC Testbeds : Microgrid Testbed
be the size of an 18-wheeler cargo container . The Microgrid Testbed housed at the Industrial IoT Lab , realistically mirrors future end deployments : Putting all the equipment in a rack , connecting the equipment with a single Ethernet cable , and having all the equipment be TSN-compliant on a small scale .
Lab Status
The Microgrid Testbed lab in Austin is simultaneously in a state of completion and development . When Jamie Smith , Director of Embedded Systems , National Instruments , opened the lab in February 2017 , he made the tongue-in-cheek comment , “ Nothing in the lab is finished ,” to denote that it is meant to be a working lab , and all the testbeds housed within are meant to be working testbeds . So , the testbed team goes to IIC meetings and networks with other people to discover whether there could be someone with tablet technology or some other software technology , etc ., wanting to contribute to the testbed .
Utility experts are now being invited to the lab to witness all the parts of the solution currently being tested . The testbed team asks the utility experts for validation that the innovations of the testbed help solve the real-world problems . Those conversations have already begun and continue to be evolving discussions , probing and identifying other problems the utilities would like the testbed team to solve and move to deploy those solutions . The team is actively working toward moving to a field deployment with other partners ’ involvement .
GRID RE-SYNCHRONIZATION
One of the wrinkles of having a microgrid is , because of the way inverters are designed today , even when running from storage , it becomes difficult or impossible to reconnect to the main grid . It can happen with today ’ s technology but it is not guaranteed and when it does happen , is not a fully controlled maneuver .
When the main grid goes down , the microgrid disconnects and continues to run . There may be a short blackout to those on the microgrid , but because it is selfsufficient , it starts up again rather quickly . However , when it is time to reconnect to the main grid , it becomes complicated . Because there is no active control over the frequency and voltage on a microgrid , the frequencies between the main grid and microgrid need to match by happenstance to reconnect . If that occurs , then there is technology on the market today that will make the connection and both the main and microgrid are in sync . If the two grids are not on the same frequency then protection systems prevent the re-connect and the microgrid will run until storage ( batteries ) are depleted , blackout again , and then reconnect . The inconvenience of two blackouts is another microgrid problem that new IIoT technology can help solve .
STANDARDS
TSN is the technology enabling the synchronization required in the Microgrid Testbed to run a stable grid on 100 % inverter sourced power . National Instruments and Cisco are both heavily involved in the TSN standard development , both from the IEEE side as well as with the Avnu Alliance . Avnu is an organization working on the promotion and usage of TSN .
DDS is an open-communication protocol that is used to implement machine to machine communication at the edge where
- 38 - September 2017