AFD Data

This dialog box includes the following areas and tabs:

• Connection Information
• Specifications
• Harmonics
• Imported Data
• Comments
• Hyperlinks

See also: Notes on AFD

Connection Information

ID Name: Uniquely identifies the adjustable frequency drive (AFD). This ID name is sometimes referred to as the AFD name, and can be up to 16 characters long. The names default to AFD-1, AFD-2, AFD-3, and so on as you enter new AFD on the one-line diagram, but you can change those names if needed.

Input Bus: ID name of the bus on the input side of AFD. The based kV of the bus is shown on the right.

Output Bus: ID name of the bus on the output side of AFD. The based kV of the bus is shown on the right.

Specifications

Figure 1: AFD Data Dialog Box—Specifications Tab

Input AC Frequency: The fixed frequency on the input side. This is specified in the System tab of Options dialog box.

Output AC Frequency: The adjustable frequency on the output of the AFD. This affects the frequency of all equipment connected on the output of the AFD.

Rating: Rated Input kVA or the motor HP of the drive.

X/R: If the AFD is regenerative, this value is used to define the short circuit X/R ratio of the contribution delivered at the input of the AFD. The Calculate button uses an ANSI standard lookup table to fill in this value. 

PF: The input power factor of the AFD for power flow simulations.

Efficiency: The efficiency of the AFD. This creates a real power increase from the output to the input of the AFD.

Input Side

Diode / IGBT: This is presently forced to IGBT only.

ANSI Code: Select Non-regen to simulate and non-regenerative drive and Regenerative to simulate a regenerative drive (which includes a short circuit contribution on the input of the AFD).

Momentary Fault x FLA: The defined bolted fault level for the input of the AFD if it is regenerative.

Output Side

IGBT / Thyristor: Select IGBT to model a source inverter on the output, or choose Thyristor to model a Thyristor output. This currently does not affect any calculations.

Fault x FLA: The fault current output of the AFD under a bolted fault condition.

Fault Time: The time that Fault x FLA is produced by the AFD under fault conditions.

Harmonics

Use the Harmonics tab to indicate whether this equipment item is introducing harmonics into your power system.

Load Type

The default is Linear, indicating the equipment does not produce harmonics. Choosing Harmonic makes the item an harmonic source and makes other fields in this tab available to edit.

Note:
For an adjustable frequency drive (AFD), the Load Type is always Harmonic.
For motors, the Load Type is Harmonic if the With Adjustable Frequency Drive (AFD) check box is selected on the Specifications tab of the motor; otherwise, it is always Linear.

Harmonic Spreadsheet

Use the spreadsheet to enter the harmonic spectrum produced by this item. You can enter up to 30 different harmonics in each equipment item. In the spreadsheet, enter the Harmonic Number (such as 5 for the 5^th harmonic), the Harmonic Current in percent of the Fundamental Amps, and the Current Angle. By indicating the current angle, you can simulate transformer phase shift effects on rectifiers so appropriate canceling can take place. The harmonic may be integer or non-integer.

Library Load

Common harmonic spectra may be entered from the device library. For instructions on how to enter your own spectra information, see Harmonics with Spectrum™. After selecting a particular device library spectrum from the Mfr and Type lists, click Import, and that spectrum is entered into the harmonic spreadsheet.

Resistance Factor

EasyPower offers two methods for calculating R_H:

• Resistance varying with a power of the harmonic (R-EXP):

R_H = R_Fund * H ^R-EXP

• Resistance varying with a percent eddy current factor (%ECF):

R_H = R_Fund * (1+ECF*H²)/(1+ECF)

EasyPower defaults all skin effect correction to R-EXP and a value of 0.5.

Fundamental Amps

Use to set the fundamental amps. The options are as follows:

• Equipment Rating sets Fundm Amps to the equipment rating of the item described in the Specifications tab. 
• User Specified activates the Fundm Amps field, enabling you to specify a value. 

To use fundamental current calculated by power flow, select Calculated from Power Flow in the Summation Fundamental Voltage area of the Harmonics Options > Control dialog box.

Imported Data

This tab is read-only and appears only if you have imported data from an SKM Data Format file. See Importing an SKM Format File for more information.

Comments

See Comments for information.

Hyperlinks

See Hyperlinks for information.

More Information