Wideband PWM Power Amp Is Suited To Inductive Loads

The 38-kW Model 263P PWM power amplifier functions as: a programmable ac power source to 3.5 kHz; a function generator with fast response output; or a highly stable, programmable, bipolar dc supply. The unit's peak high-voltage output of ±300V at 266A makes it particularly suitable for the inductive loads that characterize emerging industrial, medical and scientific applications.The amplifier develops continuous output of ±300V at 128A. Its MOSFET output bridge generates bipolar power from a single-polarity, 100V to 330V dc supply. A built-in dc-to-dc converter develops the low internal operating voltages from this single-polarity dc supply. A separate 28 vdc supply is required for fan motor power.The unit operates at a 51-kHz switching frequency, which provides output frequencies of dc to 3.5 kHz in current mode, and output settling to within 0.2% of final value in 350 µs. Total harmonic distortion at 128A_RMS and 200-Hz output is 0.2%.