Title :
Improved techniques for switching power amplifiers
Author :
Flinders, Frank M. ; Wolfs, Peter J. ; Kwong, Ken C.
Author_Institution :
Dept. of Electr. Eng., Univ. of Central Queensland, Rockhampton, Qld., Australia
fDate :
10/1/1993 12:00:00 AM
Abstract :
The control system design of a DC to 10 kHz bandwidth 45 kVA current sourced power amplifier suitable for geophysical exploration application is presented. A five-level modulation scheme has been implemented using a modified bridge topology with only four switches. This scheme gives an order-of-magnitude improvement in switching ripple and control performance over two-level modulation. Using this system, a 50 kHz switch frequency allows a 20 kHz, -3 dB bandwidth to be easily achieved. Simulation and tenth scale model test results are presented. The current output waveform reproduction is of high quality over the rated DC to 10 kHz frequency range. The total harmonic distortion is 0.3% at 1 kHz
Keywords :
Earth crust; geophysical equipment; geophysical prospecting; invertors; power amplifiers; switching circuits; terrestrial electricity; voltage control; 20 kHz; 45 kVA; 50 Hz; DC to 10 kHz bandwidth; control system design; current output waveform reproduction; current sourced power amplifier; five-level modulation scheme; geophysical exploration; inverters; modified bridge topology; ripple; simulation; switching power amplifiers; tenth scale model test results; total harmonic distortion; Bridge circuits; Conductivity; Control systems; Impedance; Magnetic field measurement; Power amplifiers; Power semiconductor switches; Switching circuits; Switching frequency; Testing;
Journal_Title :
Power Electronics, IEEE Transactions on
