Physical Data Page
- brett gebert
Summary
The physical data page charts unit variables using enriched 4 second causer pays, frequency indicator (FI) and the MMS data. It is designed to analyse unit behaviour and compare unit behaviour either between different charts or within the one chart.
How To Access
To open the "Physical Data Page" use the URL fcaspays.com or click on the line symbol in the left hand navigation bar (shown left).
Create a Chart
Click on a predefined report in the report catalogue (I nearly always use "Absolute Unit"). A chart window will appear and the contents will be shown on the right. Click "Run" to generate a chart. You should get a chart looking something like the image below.
Using the Content Window
We've defined four element types in the 4 seconds causer pays data, they are;
- UNITS (duid), note that AEMO uses the term "elements" to describe duids in the four second causer pays data,
- SYSTEM (frequency and related data from four locations),
- LOADS (duid of smelters), and
- INTERCONNECTORS (major flow lines).
You can select more than one element type to chart.
Note that the greyed out element types have already been selected.
Personally I always chart one element at a time however you may chart multiple elements in one chart.
You can select any number of elements of an element type to chart.
You can scroll through the list or shorten the list by typing the first characters of the element you are looking for.
You can select any number of variables to chart. Note that there is a separate variable list for each element type.
A description of each variable is shown when you hover over the information symbol.
Multiple Charts
The Physical Data page is designed to generate and compare multiple charts with multiple data types and variables.
Moving, duplicating, adding, deleting, editing a chart
The symbols to the left of a chart do the following (listed from top to bottom)
- Add a new chart. Note that there will be no content in this chart. It is the same as clicking "blank" in the Reports Catalogue.
- Edit the current chart. This selects the chart and the list of contents of this chart will be shown in the content window. The border of the chart will go green. Equally you can click on a chart header which is equivalent to clicking the edit icon (the pencil symbol to the left).
- Duplicate the chart. The duplicate chart will appear underneath. This is my favourite button in the entire app since you can have many charts open, change the date and select "run all" and all of the charts will update so you can quickly compare and view through the different units.
- The arrows move the chart up and down respectively.
- The rubbish bin symbol deletes the chart.
Data enhancements
Normalised data
We have created additional unit variables that have been "normalised", or made consistent with, other variables. For example RaiseReg Instruction has been added to Totalcleared so that you can compare with Generation. Similarly Totalcleared has been removed from some variables such as Generation. This makes it easy to compare units with different levels of generation because they are normalised around zero. Warning: be careful when the Totalcleared changes with a change in dispatch interval since this creates a step change in the data.
Restructured data
We've separated the element types into four separate tables. Those elements are Unit, System, Interconnector and Load.
We've also removed variable numbers and have created explicit columns with the correct label. This makes variable selection much easier.
Enriched data
We've derived new variables to help analyse the data. These new variables include:
- Basepoint: Basepoint is a 4 second variable is the linear trajectory from the unit's generation measured approximately 15 seconds before the beginning of the dispatch interval and the mw target (totalcleared) at the end of the dispatch interval. To avoid accumulating any causer pays participation factor a unit's generation trajectory should follow this line or be on the side of the line that implies supporting any frequency deviation. An example of the Basepoint is shown in the adjacent diagramme.
- Effective Enablement: Effective Enablement is a 4 second variable which is derived at the beginning of the dispatch interval and measures the amount of regulation raise the unit can be instructed to provide by AGC regulation instructions at any point assuming the unit has otherwise followed its' Basepoint. The adjacent diagramme shows this value pictorially relative to the dispatched enablement. In this diagramme the Initial MW is outside of the technical envelope where the unit can be provided with an AGC regulation instruction. Assuming the unit follows the Basepoint it will not be until half way through the dispatch interval that it can be sent (if required) any AGC raise signals. Even in the second half of the dispatch interval any unit response (driven by regulation AGC) is limited to the green arrows. In this example the average Regulation Raise Effective Enablement for the dispatch interval will be one quarter of the dispatched Regulation Raise Enablement. The Value of Effective Enablement is capped between zero and the dispatched Enablement.
- Actual Raise Headroom: Actual Raise Headroom is a 4 second variable and is the retrospective version of effective enablement. Hence it is measured relative to actual generation rather than the Basepoint. This variable is not shown in the diagramme.
| Raise Reg Effective Enablement = | min [ max (0, Raise_Reg_Enablement + Totalcleared - Basepoint), Raise Reg Enablement ] |
| Actual Raise Reg Headroom = | min [ max (0, Raise_Reg_Enablement + Totalcleared - Generation), Raise Reg Enablement ] |
