Filter Data

A filter is a passive tuned circuit that presents a low impedance “sink” to currents at a given frequency or frequencies. Filter on the Equipment Palette inserts a filter in the one-line diagram. The application of harmonic filters can cause the creation of parallel resonance below the filter tuning point (single tuned notch). The filter must be designed to minimize the impact of this resonant point.

This dialog box includes the following areas and tabs:

See Common Tabs for information on the Location, Reliability, Comments, Hyperlinks, Media Gallery, or Collected Data tabs.

Figure 1: Filter Data Dialog Box

Connection Information

Option Description
ID Name

Uniquely identifies the equipment item. The program automatically assigns a name, but you can change it, if needed. The name can be up to 16 characters long.

For filters, the program automatically assigns the names FL-1, FL-2, FL-3, and so on.

To Bus This is the ID name of the bus to which the equipment is connected. The base kV of the bus is indicated on the right.

Specifications Tab

Option Description
Type

You can select from four different types of filters. When you choose the type of filter, EasyPower makes unavailable any filter data fields that do not apply to the selected filter.

Figure 2: Filter Types
Filter Data
Resistor Resistance of resistor of the filter in ohms.
Inductor Real and imaginary impedances (ohmic resistance and inductive reactance) at system frequency in ohms.
Capacitor Bank (1 and 2) The reactive power of capacitors for the system frequency in MVARs at the voltage level specified in kilovolts.

Harmonics Tab

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

Figure 3: Harmonics Tab

Option Description
Resistance Factor

EasyPower offers two methods for calculating RH:

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

    • RH = RFund * H R-EXP

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

    • RH = RFund * (1+ECF*H2)/(1+ECF)

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

Typical Resistance Correction Factors

  R-EXP %ECF

Transformer

0.5-1.0

1.0-3.0

Utility

0.0-0.8

    -

Generator

0.3-0.6

    -

Line/Cable

0.5

    -

Reactor

0.5-1.0

0.8-3.0

Motor

0.2-0.4

    -
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.

Other Tabs

See Common Tabs for information on the Location, Reliability, Comments, Hyperlinks, Media Gallery, or Collected Data tabs.

More Information

Database Technical Reference Common Tabs
Media Gallery