Combined Alternator Map File (.aalt)
The Combined Alternator Map (.AALT) file contains data
relating to the efficiency of the alternator at various engine speeds and
current demand. The .AALT file is a CSV file containing three fields: “Amp”,
“RPM” (engine speed), and “Efficiency”. It can be created via the select file
button, or an existing map directly imported into VECTO via the File Browser.
A new combined alternator map can be created or an existing one edited using
the Combined Alternators editor module (see below). This module enables
the creation of a combined average alternator efficiency map by the advanced
auxiliaries module, using input data for one or more alternators (Pully Ratio,
Efficiency at different RPM/AMP combinations):
Alternators may be added/deleted from the list. Data for existing alternators
can be loaded into the form by double-clicking on the relevant alternator, and
the data may then be updated and saved back down.
The ‘Diagnostics’ tab provides a summary of the input data that is fed into
combined alternator map calculations:
The methodology for calculating the combined efficiency map is summarised below
(and also included in the full schematics file included with the User Manual).
Note: A simplified calculation is performed using the average of the user input
efficiency values in the model pre-run only, to keep total run-time to a
minimum (with negligible impact on the final result). :
File Format
The file uses the VECTO CSV
format.
Several example default alternator maps are provided for use until a finalised
certification procedure is in place for OEM-specific data.
Example Default Alternator Configuration for Advanced Alternator Map
Pulley Ratio: |
3.6 |
|||||
RPM |
2000 |
4000 |
6000 |
|||
|
Amps |
Efficiency |
Amps |
Efficiency |
Amps |
Efficiency |
|
10.00 |
62.00 |
10.00 |
64.00 |
10.00 |
53.00 |
I_max/2 |
27.00 |
70.00 |
63.00 |
74.00 |
68.00 |
70.00 |
I_max |
53.00 |
30.00 |
125.00 |
68.00 |
136.00 |
62.00 |
Notes: Grey cells are locked/fixed values; I_max = the maximum current in Amps.
Controls
Open file
browser if file not listed, open the Combined Alternator Map file (.aalt) if
file is present
View file contents or navigate to folder
Add button to add a newly defined alternator to the
list
Update
button, to update data for selected alternator in the list
Delete
button to remove alternator from the list
Clear Form button
Save and close file
Cancel
without saving