Why is MISO implementing this flag?
The increasing difference in magnitude between modeled flows in Unit Dispatch System (UDS) and actual flows is resulting in System Operation Limit (SOL) violations, balancing issues and frequency deviations. Out-of-market actions by operators to address these issues are causing us to deviate from market design principles. Stakeholders have expressed a desire to assist with reliability, but existing ICCP points left it unclear when there was reliability risk.
What is the Uninstructed Deviation Enhancement Flag?
It is two New ICCP setpoints that go to all Generation Resources, except Electric Storage resources (ESR). One point is to dispatch down. The second one is the reason code.
Is this change effecting only Dispatchable Intermittent Resources?
No, this change if needed for ALL generation resources except ESR.
What do generation owners need to do?
You will need to set up the new ICCP setpoints and make sure your system can then provide the message to your units. Depending upon your setup this may be through SCADA or your Energy Management System.
What are the UDE Flag and reason codes?
UDE Flag = 0
Generation Resource does not have significant Generation Shift Factor (GSF) for an active constraint.
A DIR, using the MISO Forecast, may generate above Setpoint without penalty.
UDE Flag = 1
Generation Resource does have significant GSF for an active constraint or is bound by an Operating Instruction.
A DIR Setpoint will typically be less than ecomax.
Do we need to respond differently depending on the reason code we receive?
No. The UDE Flag itself should be what is driving unit response. The reason codes are informational in nature and provide insight into the UDE Flag setting. The reason codes will also be used in future evaluation for changes to market settlement rules around uninstructed deviation.
Will the UDE Flag remain static across the five-minute interval?
Yes, unless there is an abnormal use case when UDS fails, and MISO is using DTA (Dispatch Target Adjust) it is possible for the MISO Operator to update the UDE flag within the 5-minute interval. This scenario though is highly unlikely.
When will the UDE Flag go into production?
June 3, 2025
Will the UDE flag and reason code be available in the Backup Dispatch instructions used during times of ICCP failure?
Yes, both will be available.
How will the UDE flag impact the functionality and expectations when UDS is down and MISO is leveraging Dispatch Target Adjustment (DTA)?
The DTA logic has been enhanced to incorporate the UDE flag from the last known UDS solution. Expectations under DTA are similar under UDS. When the UDE flag is true, units need to stick to their 4-second setpoints. Additionally, the specific logic for DIRs and DTA has been modified to assist MISO in better managing congestion. If UDE=1 the DIR setpoint max will be capped at the last known UDS dispatch target. DIRs can be dispatched down below this point but no higher. If UDE=0, the current DTA logic will be effective where DIRs are treated as off-control and setpoints will echo unit output.
How can units test the two new ICCP points prior to UDE go-live?
The two new ICCP points are already available in the Production environment. Resources can conduct open loop testing on these UDE points by emailing ICCPmodeling@misoenergy.org to schedule testing with the ICCP modeling team, which will use the same process as a normal open loop test of a unit.
Can a non-DIR resource have a UDE Flag = 0? What are MISO's expectations in this situation?
The logic for determining the UDE flags is the same for both DIRs and traditional generation. However, the current settlement rules and expectations (which are not changing with the UDE flag implementation) aren’t necessarily the same. DIRs are exempted from the traditional tolerance band for excessive/deficient energy settlements, as long as they are utilizing the MISO forecast and aren’t being dispatched down for congestion. However, traditional generators do not have that exemption. As such, even if the UDE Flag = 0 for a traditional generator, we still expect them to maintain close tracking with their dispatch targets. A common situation in which the UDE Flag may be = 0 for a traditional generator is when they are being dispatched to their ecomax and don’t have significant GSF to active congestion.
Why use a real data type, instead of using a discrete data type, for an integer?
The Discrete data type isn't specific to integers but is either a 2 state or 4 state devices in our EMS systems (OPEN CLOSE TRANSIT INVALID). So, we can't send integers without using an analog type, which makes using the Real data type more convenient even in the Unit status example.
Is there a purpose for making discrete reason code, modes, or statuses in ICCP a Real data type instead of Discrete data type? Is this necessary for particular software vendors?
Yes, and yes basically.
For More Information:
MSC Presentation