Harmonic Frequency Scan Software
One particular concern with harmonics is the resonance condition in the power system. Because of the existence of both inductive components and capacitive components in the system, at certain frequencies, resonance conditions might occur at some buses. If the resonance occurs at a bus where a harmonic current is injected into the system, an overvoltage condition will be observed.
The ETAP Frequency Scan module is the best tool to investigate the system resonance problem. It calculates and plots the magnitudes and phase angles of bus driving point impedance over a frequency range specified by the user; thus, any parallel resonance condition and its resonance frequency can be clearly identified. The harmonic frequency scan study also allows users to tune their harmonic filter parameters and test the final results.
In Harmonic Frequency Scan module, the frequency range for scanning is defined by the user, which starts from the fundamental frequency and can go as high as the user needs.
The results from the harmonic frequency scan study are reported in reports which includes the system input data, and a tabulation listing bus driving point impedances. The same tabulated information is also given on the one-line diagram, as well as in a plot format.
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Harmonic Frequency Scan Analysis Key Features
- User-definable frequency range
- Identify resonance conditions
- User-customizable plots
Harmonic Frequency Scan Module Capabilities
- Same system and component modeling capabilities for harmonic load flow and fundamental load flow
- Modeling of frequency dependency of rotary machine impedance
- Modeling of nonlinearity and frequency dependency of cable/line and transformer impedance
- Modeling of frequency dependency of other power system components and loads
- Considering transformer phase shifting
- Considering machine and transformer winding connections and grounding types
- Built-in harmonic filters in different types
- Automatic harmonic filter sizing based on different criteria
- User-definable harmonic frequency scan range and step
- Graphic one-line display of study results
- Slider bar to display bus driving point impedance magnitude and phase angle at selected frequencies
- Graphic plots of bus driving point impedance in ohms for viewing and printing
- Graphic plots of bus driving point impedance phase angle for viewing and printing
- Text report for input data, fundamental load flow results, tabulated bus driving point impedance magnitudes and phase angles
- Report resonance frequencies and magnitudes