Test Specification TC17.TS2
Characterization of recovery from failure
Test Specification Definition
| ID | TC17.TS2 |
|---|
| Reference to Test Case | TC17 |
|---|
| Title of Test | Characterization of recovery from failure |
|---|
| Test Rationale | This test will characterize the response of the fault recovery mechanism. The results obtained will also allow a performance comparison with the baseline system. |
|---|
| Specific Test System
(graphical) | 
|
|---|
| Target measures | - Time to restoration of service delivery
- Deviation of service delivered from service requested
|
|---|
| Input and output parameters | - Input: Level of base load [kW]
- Input: Service requested (by DSO) to dispatch unit
- Input: Time of fault occurrence [s]
- Output: Active power production/consumption at individual DERs [kW]
- Output: Active power sum flow at grid connection [kW]
|
|---|
| Test Design | The test can be performed as a hardware experiment, a simulation experiment or a combination of the two. - Configure grid, DER units and base load to bring system into initial state (t=t0)
- At t=t1, request a load relief service from the dispatch unit, wait for aggregators to activate DER units. Measure the effectiveness of the service delivery (impact on grid) after stabilization.
- At t=t2, command fault simulator to disrupt communication to aggregator 1
- Determine the points in time t=t3 where the dispatch unit has noticed the fault, and t=t4 where aggregator 2 has rescheduled.
- Continuously measure the effectiveness of the service delivery in order to determine the disruption to service delivery during t3<t<t4.
- Verify that the effectiveness of service delivery after t4 is comparable to before the fault (t<t2).
|
|---|
| Initial system state | - No service requested by dispatch unit
- All DERs in neutral state (not delivering a service)
- Feeder in overload condition by combined baseload+DER consumption
- Fault simulator in bypass state (no fault)
|
|---|
| Evolution of system state and test signals | - Base load continues to change, following e.g. a random pattern
- Aggregator response tracks changes in base load
- Dispatch unit moves from “service delivery” to “fault recovery” and back to “service delivery”
|
|---|
| Other parameters | |
|---|
| Temporal resolution | Electrical system measurements: 1s. Logging of ICT events (messages exchanged, communication fault event etc.) using timestamps with at least 1ms resolution. |
|---|
| Source of uncertainty | Residual time synchronization difference between ICT entities |
|---|
| Suspension criteria / Stopping criteria | Elapsed time (fixed length experiment) |
|---|