PLEXOS 6.201 Release Notes
- Upgrade Compatibility
- Changes
- Features
- New Inputs
- Moved Inputs
- Input Changes
- New Outputs
- Changed Outputs
1. Upgrade Compatibility
Your 6.200 (or 5.200) database will be upgraded automatically and should function just as before. There should be no manual upgrading required.
2. Changes
N/A
3. Features
3.1. Interregional and Interzonal Wheeling
This feature allows for the efficient formulation of interregional and interzonal wheeling charges, without having to define the wheeling charges on the a line-by-line basis:
- In input, added Region Regions Wheeling Charge to define the wheeling charge for all flows between regions. Same is repeated for Zone objects.
- In output, added Region Wheeling Revenue, Wheeling Cost Region Regions Wheeling Cost. Same is repeated for Zone class.
3.2. Additional Transmission Controls
Several new options have been added to the transmission settings, to allow finer control of the transmission algorithms:
- Added option Transmission SCUC Interface Constraints Enabled to control enforcement of Interface limits in the SCUC. Default behaviour is that lines are 'on', transformers 'on', and interfaces 'off'. Setting this switch causes interfaces to be monitored in SCUC by default.
- Added Interface Overload Max rating and Overload Min Rating.
- Added Transformer Overload Rating, Enforce Limits, Must Report, Limit Penalty similar to the existing Line properties, and now support import of these data from PSS/E.
- Added Node Allow Unserved Energy and Allow Dump Energy flags to give finer control of these variables.
- Added Transmission Bound Node Phase Angles to turn on/off phase angle bounds and Max Absolute Phase Angle to set the limit (default of 2 radians).
- Added Line/Transformer/Interface/Constraint Formulate Upfront flag i.e. individual for each element so we can force-in certain key constraints.
Added controlling parameters for initial transmission limit convergence:
- Transmission Limit Bootstrap Initial Threshold,
- Transmission Limit Bootstrap Initial Threshold Decrement.
This new feature tries to limit the number of slack transmission constraints added by starting with a higher limit tolerance and stepping down in iterations. Also added Transmission Max Limit Iterations to set the iteration limit in any one call to enforce the limits. This can be set to 0 for debugging.
3.3. Generator Run Up and Run Down Rates
It's always been possible to model run up and run down rates using the Start Profile and Shutdown Profile properties, but when you start doing 5-minute modelling, which is becoming increasingly popular, the input schema for those properties can be cumbersome. Hence we have added the following simplified inputs:
- Added Generator Run Up Rate as a shortcut to defining a Start Profile when the run-up ramp rate is constant.
- Similarly for running down added Run Down Rate and shortcut to defining Shutdown Profile.
3.4. Generator Formulation Control
Relevant to MIP models:
- Added the Production Formulate Upfront switch to force upfront formulation of Start/Stop logic constraints. These constraints are rarely required and by default are added in iterations, which can be expensive in MIP models.
3.5. Storage Model and Volume Controls
- Added Storage Model attribute supplementing the file setting of "Hydro Model" and allows the hydro storage model to be set per Storage object.
- Added Storage Internal Volume Scalar which sets the internal scalar. Setting the scalar by storage can improve scaling in the mathematical program.
3.6. Reserve Shortage Pricing Controls
Added Reserve Price Cap and Price Floor to control the output price of reserve when there is shortage or oversupply of the Reserves.
3.7. Additional Diagnostic and Log Controls
Added the following Diagnostic switches:
- MPS Files = Yes/No (No): controls writing of MPS format files
- Generic Names = Yes/No (No): uses generic (x1, x2, etc) names in math program files
- Times = Yes/No (Yes): controls printing of time parts in logs
- Task Size = Yes/No (Yes): controls printing of task size in logs
- Step Summary = Yes/No (Yes): controls printing of step summary in logs
- Sample Summary = Yes/No (No): controls of sample summary in logs
- Clear Existing = Yes/No (Yes): if existing diagnostics files should be cleared from the output folder
3.8. RSI Enhancement
Added Generator Strategic Reference Price for use in RSI as a baseline marginal cost against which future years' mark-ups are applied. Avoids the problem of the RSI mark-ups escalating unrealistically with fuel prices.
4. New Inputs
See above.
5. Moved Inputs
N/A
6. Input Changes
The following minor changes have been made to input properties:
- Generator Rating Factor: It is now allowed to define both Rating and Rating Factor. This can be useful when you want to randomise the Generator Rating with a frequency other than every period. The 'final' rating used is the product of Rating and Rating Factor.
- Line Limit Penalty: If this input is defined with a zero value in all periods of the horizon, the checking of line limits is disabled i.e. it is assumed flow is unlimited.
- Generator Retirement Cost: The unit for this input has been changed to $000 from $/kW.
7. New Outputs
The following new output properties are added:
- Region and Zone Importing Transformers, Exporting Transformers, Inter and Intraregional, Transformers collections.
- Added Transformer Is Violated, Hours Violated Back, Violation, Violation Back, Violation Cost, Violation Cost Back to support Limit Penalty input.
- Added Generator, Region, Zone output Total Generation Cost which is all costs including Generation Cost, Start & Shutdown Cost, and emissions costs.
- Added Generator Units Shutdown.
8. Changed Outputs
N/A