DC OPF (#543)

* DC OPF changes: Added DC OPF method for power flow calculations, Added IEEE 9-Bus test case (for both single time-stamp and time-series), Update transmission.jl with splitting DC OPF and non-DC-OPF

Documentation for DC-OPF: deactivate network expansion when dcopf is used, changed angle limit unit to radiant and modified column names for consistency, fixed input files, computation of DC-OPF coefficient, and write_angles.jl to output radians not degrees, Update investment_transmission.jl, Modified the writing of angles and flows to only write hourly values, fixed automated tests

---------

Co-authored-by: Chakrabarti, Sambuddha (Sam) <[email protected]>
Co-authored-by: Filippo <[email protected]>
Co-authored-by: lbonaldo <[email protected]>

CHANGELOG.md

@@ -25,6 +25,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Maintenance formulation for thermal-commit plants (#556).
 - Add new tests for GenX: three-zone, multi-stage, electrolyzer, VRE+storage, 
   piecewise_fuel+CO2, and TDR (#563 and #578).
+- Added a DC OPF method (#543) to calculate power flows across all lines
 - Added write_operating_reserve_price_revenue.jl to compute annual operating reserve and regulation revenue.
   Added the operating reserve and regulation revenue to net revenue (PR # 611)
 - Add functions to compute conflicting constraints when model is infeasible if supported by the solver (#624).

Example_Systems/DC_OPF/IEEE_9BUS/Demand_data.csv

@@ -0,0 +1,5 @@
+Voll,Demand_Segment,Cost_of_Demand_Curtailment_per_MW,Max_Demand_Curtailment,$/MWh,Rep_Periods,Timesteps_per_Rep_Period,Sub_Weights,Time_Index,Demand_MW_z1,Demand_MW_z2,Demand_MW_z3,Demand_MW_z4,Demand_MW_z5,Demand_MW_z6,Demand_MW_z7,Demand_MW_z8,Demand_MW_z9
+2000000,1,1,1,2000,1,1,1,1,0,0,0,0,90,0,100,0,125
+,2,0.9,0.04,1800,,,,,,,,,,,,,
+,3,0.55,0.024,1100,,,,,,,,,,,,,
+,4,0.2,0.003,400,,,,,,,,,,,,,

Example_Systems/DC_OPF/IEEE_9BUS/Fuels_data.csv

@@ -0,0 +1,3 @@
+Time_Index,natural_gas,coal,nuclear,None
+0,0.05306,0.05306,0.05306,0.05306
+1,0.05306,0.05306,0.05306,0.05306

Example_Systems/DC_OPF/IEEE_9BUS/Generators_variability.csv

@@ -0,0 +1,3 @@
+Time_Index,z1_natural_gas,z2_natural_gas,z3_natural_gas
+0,1,1,1
+1,1,1,1

Example_Systems/DC_OPF/IEEE_9BUS/Network.csv

@@ -0,0 +1,10 @@
+,Network_zones,Network_Lines,Start_Zone,End_Zone,Line_Max_Flow_MW,transmission_path_name,distance_mile,Line_Loss_Percentage,Line_Max_Reinforcement_MW,Line_Reinforcement_Cost_per_MWyr,DerateCapRes_1,CapRes_1,CapRes_Excl_1,Angle_Limit_Rad,Line_Voltage_kV,Line_Resistance_Ohms,Line_Reactance_Ohms
+BUS1,z1,1,1,4,250,BUS1_to_BUS4,0.5,0.015,500,12000,0.95,0,0,0.785398,345,0,68.5584
+BUS2,z2,2,4,5,250,BUS4_to_BUS5,0.5,0.015,500,12000,0.95,0,0,0.785398,345,20.23425,109.503
+BUS3,z3,3,5,6,150,BUS5_to_BUS6,0.5,0.015,500,12000,0.95,0,0,0.785398,345,46.41975,202.3425
+BUS4,z4,4,3,6,300,BUS3_to_BUS6,0.5,0.015,500,12000,0.95,0,0,0.785398,345,0,69.74865
+BUS5,z5,5,6,7,150,BUS6_to_BUS7,0.5,0.015,500,12000,0.95,0,0,0.785398,345,14.163975,119.9772
+BUS6,z6,6,7,8,250,BUS7_to_BUS8,0.5,0.015,500,12000,0.95,0,0,0.785398,345,10.117125,85.698
+BUS7,z7,7,8,2,250,BUS8_to_BUS2,0.5,0.015,500,12000,0.95,0,0,0.785398,345,0,74.390625
+BUS8,z8,8,8,9,250,BUS8_to_BUS9,0.5,0.015,500,12000,0.95,0,0,0.785398,345,38.088,191.63025
+BUS9,z9,9,9,4,250,BUS9_to_BUS4,0.5,0.015,500,12000,0.95,0,0,0.785398,345,11.9025,101.17125

Example_Systems/DC_OPF/IEEE_9BUS/README.md

@@ -0,0 +1,17 @@
+# IEEE 9-BUS Test case 
+
+They are total of 3 generators and three loads
+
+To run the model, first navigate to the example directory at `GenX/Example_Systems/DC_OPF/IEEE_9BUS`:
+
+`cd("Example_Systems/DC_OPF/IEEE_9BUS")`
+
+Next, ensure that your settings in `Settings/genx_settings.yml` are correct.
+The default settings use the solver HiGHS.
+Other optional policies include minimum capacity requirements, a capacity reserve margin, and more. 
+
+Once the settings are confirmed, run the model with the `Run.jl` script in the example directory:
+
+`include("Run.jl")`
+
+Once the model has completed, results will write to the `Results` directory.

Example_Systems/DC_OPF/IEEE_9BUS/Resources/thermal.csv

@@ -0,0 +1,4 @@
+Resource,Zone,Model,New_Build,Can_Retire,Existing_Cap_MW,Min_Cap_MW,Max_Cap_MW,Inv_Cost_per_MWyr,Fixed_OM_Cost_per_MWyr,Var_OM_Cost_per_MWh,Start_Cost_per_MW,Start_Fuel_MMBTU_per_MW,Cap_Size,Heat_Rate_MMBTU_per_MWh,Fuel,Min_Power,Ramp_Up_Percentage,Ramp_Dn_Percentage,Up_Time,Down_Time,Reg_Max,Rsv_Max,Reg_Cost,Rsv_Cost,MGA,Resource_Type,region,cluster
+z1_natural_gas,1,1,0,1,250,10,0,0,5,0.1,0,0,250,0.1,natural_gas,0.04,1,1,0,0,1,1,0,0,1,natural_gas,BUS1,1
+z2_natural_gas,2,1,0,1,300,10,0,0,1.2,0.1,0,0,300,0.1,natural_gas,0.033333333,1,1,0,0,1,1,0,0,1,natural_gas,BUS2,1
+z3_natural_gas,3,1,0,1,270,10,0,0,1,0.1,0,0,270,0.1,natural_gas,0.037037037,1,1,0,0,1,1,0,0,1,natural_gas,BUS3,1

Example_Systems/DC_OPF/IEEE_9BUS/Run.jl

@@ -0,0 +1,3 @@
+using GenX
+
+ run_genx_case!(dirname(@__FILE__))

Example_Systems/DC_OPF/IEEE_9BUS/Settings/cplex_settings.yml

@@ -0,0 +1,10 @@
+# CPLEX Solver Parameters
+Feasib_Tol: 1.0e-05 # Constraint (primal) feasibility tolerances.
+Optimal_Tol: 1e-5 # Dual feasibility tolerances.
+Pre_Solve: 1 # Controls presolve level.
+TimeLimit: 110000 # Limits total time solver.
+MIPGap: 1e-3 # Relative (p.u. of optimal) mixed integer optimality tolerance for MIP problems (ignored otherwise).
+Method: 2 # Algorithm used to solve continuous models (including MIP root relaxation).
+BarConvTol: 1.0e-08 # Barrier convergence tolerance (determines when barrier terminates).
+NumericFocus: 0 # Numerical precision emphasis.
+SolutionType: 2 # Solution type for LP or QP.

Example_Systems/DC_OPF/IEEE_9BUS/Settings/genx_settings.yml

@@ -0,0 +1,21 @@
+OverwriteResults: 0 # Overwrite existing results in output folder or create a new one; 0 = create new folder; 1 = overwrite existing results
+PrintModel: 1 # Write the model formulation as an output; 0 = active; 1 = not active
+NetworkExpansion: 0 # Transmission network expansionl; 0 = not active; 1 = active systemwide
+Trans_Loss_Segments: 0 # Number of segments used in piecewise linear approximation of transmission losses; 1 = linear, >2 = piecewise quadratic
+Reserves: 0 # Regulation (primary) and operating (secondary) reserves; 0 = not active, 1 = active systemwide
+EnergyShareRequirement: 0 # Minimum qualifying renewables penetration; 0 = not active; 1 = active systemwide
+CapacityReserveMargin: 0 # Number of capacity reserve margin constraints; 0 = not active; 1 = active systemwide
+CO2Cap: 0 # CO2 emissions cap; 0 = not active (no CO2 emission limit); 1 = mass-based emission limit constraint; 2 = load + rate-based emission limit constraint; 3 = generation + rate-based emission limit constraint
+StorageLosses: 0 # Energy Share Requirement and CO2 constraints account for energy lost; 0 = not active (DO NOT account for energy lost); 1 = active systemwide (DO account for energy lost)
+MinCapReq: 0  # Activate minimum technology carveout constraints; 0 = not active; 1 = active
+MaxCapReq: 0  # Activate maximum technology carveout constraints; 0 = not active; 1 = active
+ParameterScale: 0 # Turn on parameter scaling wherein load, capacity and power variables are defined in GW rather than MW. 0 = not active; 1 = active systemwide
+WriteShadowPrices: 1 # Write shadow prices of LP or relaxed MILP; 0 = not active; 1 = active
+UCommit: 0 # Unit committment of thermal power plants; 0 = not active; 1 = active using integer clestering; 2 = active using linearized clustering
+TimeDomainReductionFolder: "TDR_Results" # Directory name where results from time domain reduction will be saved. If results already exist here, these will be used without running time domain reduction script again.
+TimeDomainReduction: 0 # Time domain reduce (i.e. cluster) inputs based on Load_data.csv, Generators_variability.csv, and Fuels_data.csv; 0 = not active (use input data as provided); 0 = active (cluster input data, or use data that has already been clustered)
+ModelingToGenerateAlternatives: 0 # Modeling to generate alternatives; 0 = not active; 1 = active. Note: produces a single solution as output
+ModelingtoGenerateAlternativeSlack: 0.1 # Slack value as a fraction of least-cost objective in budget constraint used for evaluating alternative model solutions; positive float value
+ModelingToGenerateAlternativeIterations: 3 # Number of MGA iterations with maximization and minimization objective
+MethodofMorris: 0 #Flag for turning on the Method of Morris analysis
+DC_OPF: 1 #Flag for running DC-OPF: 0 = not active (transport model); 1 = active

Example_Systems/DC_OPF/IEEE_9BUS/Settings/gurobi_settings.yml

@@ -0,0 +1,15 @@
+# Gurobi Solver Parameters
+# Common solver settings
+Feasib_Tol: 1.0e-05           # Constraint (primal) feasibility tolerances.
+Optimal_Tol: 1e-5             # Dual feasibility tolerances.
+TimeLimit: 110000             # Limits total time solver.
+Pre_Solve: 1                  # Controls presolve level.
+Method: 2                    # Algorithm used to solve continuous models (including MIP root relaxation).
+
+#Gurobi-specific solver settings
+MIPGap: 1e-3                  # Relative (p.u. of optimal) mixed integer optimality tolerance for MIP problems (ignored otherwise).
+BarConvTol: 1.0e-06          # Barrier convergence tolerance (determines when barrier terminates).
+NumericFocus: 0               # Numerical precision emphasis.
+Crossover: 0               # Barrier crossver strategy.
+PreDual: 0                    # Decides whether presolve should pass the primal or dual linear programming problem to the LP optimization algorithm.
+AggFill: 10                   # Allowed fill during presolve aggregation.

Example_Systems/DC_OPF/IEEE_9BUS/Settings/highs_settings.yml

@@ -0,0 +1,11 @@
+# HiGHS Solver Parameters
+# Common solver settings
+Feasib_Tol: 1.0e-05        # Primal feasibility tolerance # [type: double, advanced: false, range: [1e-10, inf], default: 1e-07]
+Optimal_Tol: 1.0e-05       # Dual feasibility tolerance # [type: double, advanced: false, range: [1e-10, inf], default: 1e-07]
+TimeLimit: 1.0e23              # Time limit # [type: double, advanced: false, range: [0, inf], default: inf]
+Pre_Solve: choose          # Presolve option: "off", "choose" or "on" # [type: string, advanced: false, default: "choose"]
+Method: ipm             #HiGHS-specific solver settings # Solver option: "simplex", "choose" or "ipm" # [type: string, advanced: false, default: "choose"]
+
+# run the crossover routine for ipx
+# [type: string, advanced: "on", range: {"off", "on"}, default: "off"]
+run_crossover: "off"

Example_Systems/DC_OPF/IEEE_9BUS/Settings/time_domain_reduction_settings.yml

@@ -0,0 +1,151 @@
+#####
+#
+#  TIME DOMAIN REDUCTION SETTINGS
+#
+#  Set parameters here that organize how your full timeseries
+#   data will be divided into representative period clusters.
+#   Ensure that time_domain_reduction is set to 1 in GenX_settings.yml
+#   before running. Run within GenX or use PreCluster.jl to test and
+#   examine representative period output before proceeding.
+#   Specify your data input directory as inpath within Run_test.jl
+#   or PreCluster.jl.
+#
+#####
+
+  #   - TimestepsPerRepPeriod
+  #   Typically 168 timesteps (e.g., hours) per period, this designates
+  #   the length of each representative period.
+TimestepsPerRepPeriod: 1
+
+  #   - ClusterMethod
+  #   Either 'kmeans' or 'kmedoids', this designates the method used to cluster
+  #   periods and determine each point's representative period.
+ClusterMethod: 'kmeans'
+
+  #   - ScalingMethod
+  #   Either 'N' or 'S', this designates directs the module to normalize ([0,1])
+  #   or standardize (mean 0, variance 1) the input data.
+ScalingMethod: "S"
+
+  #   - MaxPeriods
+  #   The maximum number of periods - both clustered periods and extreme periods -
+  #   that may be used to represent the input data. If IterativelyAddPeriods is on and the
+  #   error threshold is never met, this will be the total number of periods.
+MaxPeriods: 11
+
+  #   - MinPeriods
+  #   The minimum number of periods used to represent the input data. If using
+  #   UseExtremePeriods, this must be at least the number of extreme periods requests. If
+  #   IterativelyAddPeriods if off, this will be the total number of periods.
+MinPeriods: 8
+
+  #   - IterativelyAddPeriods
+  #   Either 'yes' or 'no', this designates whether or not to add periods
+  #   until the error threshold between input data and represented data is met or the maximum
+  #   number of periods is reached.
+IterativelyAddPeriods: 1
+
+  #   - IterateMethod
+  #   Either 'cluster' or 'extreme', this designates whether to add clusters to
+  #   the kmeans/kmedoids method or to set aside the worst-fitting periods as a new extreme periods.
+  #   The default option is 'cluster'.
+IterateMethod: "cluster"
+
+  #   - Threshold
+  #   Iterative period addition will end if the period farthest (Euclidean Distance)
+  #   from its representative period is within this percentage of the total possible error (for normalization)
+  #   or ~95% of the total possible error (for standardization). E.g., for a threshold of 0.01,
+  #   every period must be within 1% of the spread of possible error before the clustering
+  #   iterations will terminate (or until the max number of periods is reached).
+Threshold: 0.05
+
+  #   - nReps
+  #   The number of times to repeat each kmeans/kmedoids clustering at the same setting.
+nReps: 100
+
+  #   - LoadWeight
+  #   Default 1, this is an optional multiplier on load columns in order to prioritize
+  #   better fits for load profiles over resource capacity factor profiles.
+LoadWeight: 1
+
+  #   - WeightTotal
+  #   Default 8760, the sum to which the relative weights of representative periods will be scaled.
+WeightTotal: 24
+
+  #   - ClusterFuelPrices
+  #   Either 'yes' ro 'no', this indicates whether or not to use the fuel price
+  #   time series in Fuels_data.csv in the clustering process. If 'no', this function will still write
+  #   Fuels_data_clustered.csv with reshaped fuel prices based on the number and size of the
+  #   representative weeks, assuming a constant time series of fuel prices with length equal to the
+  #   number of timesteps in the raw input data.
+ClusterFuelPrices: 1
+
+  #   - MultiStageConcatenate
+  #   (Only considered if MultiStage = 1 in genx_settings.yml)
+  #   If 1, this designates that the model should time domain reduce the input data
+  #   of all model stages together. Else if 0, the model will time domain reduce each
+  #   stage separately
+MultiStageConcatenate: 0
+
+  #   - UseExtremePeriods
+  #   Either 'yes' or 'no', this designates whether or not to include
+  #   outliers (by performance or load/resource extreme) as their own representative periods.
+  #   This setting automatically includes the periods with maximum load, minimum solar cf and
+  #   minimum wind cf as extreme periods.
+UseExtremePeriods: 1
+
+# STILL IN DEVELOPMENT - Currently just uses integral max load, integral min PV and wind.
+#   - ExtremePeriods
+#   Use this to define which periods to be included among the final representative periods
+#   as "Extreme Periods".
+#   Select by profile type: load ("Load"), solar PV capacity factors ("PV"), and wind capacity factors ("Wind").
+#   Select whether to examine these profiles by zone ("Zone") or across the whole system ("System").
+#   Select whether to look for absolute max/min at the timestep level ("Absolute")
+#      or max/min sum across the period ("Integral").
+#   Select whether you want the maximum ("Max") or minimum ("Min") (of the prior type) for each profile type.
+ExtremePeriods:
+   Load:
+      Zone:
+         Absolute:
+            Max: 0
+            Min: 0
+         Integral:
+            Max: 0
+            Min: 0
+      System:
+         Absolute:
+            Max: 1
+            Min: 0
+         Integral:
+            Max: 0
+            Min: 0
+   PV:
+      Zone:
+         Absolute:
+            Max: 0
+            Min: 0
+         Integral:
+            Max: 0
+            Min: 1
+      System:
+         Absolute:
+            Max: 0
+            Min: 0
+         Integral:
+            Max: 0
+            Min: 0
+   Wind:
+      Zone:
+         Absolute:
+            Max: 0
+            Min: 0
+         Integral:
+            Max: 0
+            Min: 1
+      System:
+         Absolute:
+            Max: 0
+            Min: 0
+         Integral:
+            Max: 0
+            Min: 0