Method and apparatus for welding with short clearing prediction

A welding-type system, comprising:

• a power supply with a control input, wherein the power supply provides a welding-type output having an output voltage, and wherein the power supply includes a feedback circuit that provides a feedback signal responsive to the output voltage;
• and
• a controller, wherein the controller includes a short clearing prediction module that receives the feedback signal responsive to the output voltage, and determines a first derivative with respect to time of the feedback signal, and further calculates a predicted output voltage from the first derivative, and wherein the short clearing prediction module includes a comparison module that receives the feedback signal and a value that is a function of the predicted output voltage, wherein the value that is a function of the predicted output voltage is greater than the predicted output voltage by at least one of an offset and a multiple of the predicted output voltage, and wherein the short clearing prediction module determines that the short is about to clear and the comparison module is programmed to determine if the feedback signal exceeds or equals the value that is a function of the predicted output voltage, and wherein the controller provides a signal to the control input, causing an output current to decrease, in response to the short clearing prediction module determining that the short is about to clear;
• wherein the controller includes a multiplier that calculates the predicted output voltage, and is connected to the comparison module to provide the value that is a function of the predicted output voltage to the comparison module, and wherein the short clearing prediction module further is programmed to include a second comparison module that compares a one of the first derivative of the feedback signal and the feedback signal to a second threshold, and wherein the short clearing prediction module is further programmed to determine that the short is about to clear when the comparison module determines that the one of the first derivative of the feedback signal and the feedback signal exceeds or equals the second threshold, and wherein the controller provides a signal to the control input, causing an output current to decrease, in response to the short clearing prediction module determining that the short is about to clear.