ED tries to allocate available generation to meet the current system load at lowest cost. The classic text is Wood & Wollenburg.
In this mathematical formulation generators are indexed by . is a generator’s power output and is its cost function. The objective is to minimize the total cost. There are two constraints:
To define a simple ED problem, Minpower requires two spreadsheets. The first describes the generator parameters (generators.csv):
"heat rate equation","P min","P max","fuel cost"
"225+8.4P+0.0025P^2",45,450,0.8
"729+6.3P+0.0081P^2",45,350,1.02
"400+7.5P+0.0025P^2",47.5,450,0.9
The second simply describes the load (loads.csv):
name,power
load,500
Note
For more information about what options you can specify in each spreadsheet see: Creating a Problem.
Save the two spreadsheets above into into a folder (call it mydispatch) and run:
minpower mydispatch
This particular problem is also Minpower built-in test case (based on Wood & Wollenburg Problem 3.7), so if you haven’t been following along, to solve it, call:
minpower ed-WW-3-7
The result is a plot (dispatch.png):
and a spreadsheet (dispatch.csv):
These outputs show that the problem’s two generators (named cheap and expensive) are being dispatched so that their incremental costs (the vertical axis in the plot and IC in the spreadsheet) are near equal. Each generator’s linearized incremental cost is shown in the plot, with a dot on its current real power output (P). Because this is a dispatch each generator is on (u=True) unless specified in the input spreadsheet.