NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Distortion and regulation characterization of a Mapham inverterOutput-voltage total harmonic distortion (THD) of a 20-kHz, 6-kVA Mapham resonant inverter is characterized as a function of its switching-to-resonant frequency ratio, f(s)/f(r), using the EASY5 Engineering Analysis System. EASY5 circuit simulation results are compared with hardware test results to verify the accuracy of the simulations. The effects of load on the THD versus f(s)/f(r) is investigated for resistive, leading, and lagging power factor load impedances. The effect of the series output capacitor on the Mapham inverter output-voltage distortion and inherent load regulation is characterized under loads of various power factors and magnitudes. An optimum series capacitor value which improves the inherent load regulation to better than 3 percent is identified. The optimum series capacitor value is different from the value predicted from a modeled frequency domain analysis. An explanation is proposed which takes into account the conduction overlap in the inductor pairs during steady-state inverter operation, which decreases the effective inductance of a Mapham inverter. A fault protection and current limit method is discussed which allows the Mapham inverter to operate into a short circuit, even when the inverter resonant circuit becomes overdamped.
Document ID
19900051070
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Sundberg, Richard C.
(General Dynamics Corp. Space Systems Div., San Diego, CA, United States)
Brush, Andrew S.
(NASA Lewis Research Center; Sverdrup Technology, Inc. Cleveland, OH, United States)
Button, Robert M.
(NASA Lewis Research Center Cleveland, OH, United States)
Patterson, Alexander G.
(NASA Lewis Research Center; Analex Corp. Cleveland, OH, United States)
Date Acquired
August 14, 2013
Publication Date
January 1, 1989
Subject Category
Electronics And Electrical Engineering
Meeting Information
Meeting: IECEC-89
Location: Washington, DC
Country: United States
Start Date: August 6, 1989
End Date: August 11, 1989
Accession Number
90A38125
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available