ENHANCED POWER FACTOR CORRECTION FOR WELDING AND CUTTING POWER SUPPLIES

摘要

Enhanced power factor correction for a welding-based power supply includes a controller that tracks a rectified input voltage waveform and detects zero-crossing events therein. The controller generates an ideal sinusoidal current reference signal synchronized by expected zero-crossings in the supplied power. The reference signal is used in a current control loop within the controller to control the power electronics such that the waveform of the current drawn by the power supply matches the waveform of the input voltage. The frequency of the supplied power may be calculated using the expected zero-crossings and used to adjust the expected zero-crossings.