Data acquisition and analysis system for power electronic circuits

A LabVIEW based virtual instrument for data acquisition and analysis for power electronic circuits is presented. The LabVIEW software defining this instrument is described in detail with reference to the instrument front panel and the program block diagram. The data acquisition system consists of a Power Macintosh 7100/66 running LabVIEW4 with an NI-488 card controlling a Tektronix TDS 420 oscilloscope via General Purpose Interface Bus (GPIB). Four channels of data can be acquired and saved in Matlab or Spreadsheet format. The program performs harmonic analysis and power factors calculations associated with power electronic circuits.;As an introduction to the subject harmonics, the major power system disturbances are briefly described. The "classical" harmonic producers are discussed and diode bridge rectifiers are reviewed with emphasis on current distortion and power factors.;The data acquisition system is employed in experiments including different rectifier circuits, voltage source inverter drives and novel topologies of rectifiers with resonant harmonic correction units. The performance of the virtual instrument is demonstrated by plots of acquired data, harmonic spectrums and calculated quality factors.