The Research on Effect of Zero Order Holder and First-order Lag to High Performance Digital Arc-welding Power Supply

摘要

W artykule wykazano, ?e podtrzymanie zerowego rz?du i opó?nienie pierwszego rz?du ograniczaj? stabilno?? uk?adu. Bazuj?c na tym za?o?eniu okre?lono parametry uk?adu sterowania w stanie nieobci??onym oraz w?a?ciwo?ci statyczne i dynamiczne, szczególnie w celu redukcji dodatkowego pr?du zwarcia.%Digital control become more attractive because of their stable control precision and flexible control strategy in welding occasions. In this paper, the impact of zero order holder and first-order lag to system performance Is analyzed firstly and it is conclude that zero order holder and first-order lag will reduce the stability of the system. Also, the trend of stability will change with damp PF-FB power supply in both voltage loop control and current loop control. Based on those conclusion, the control parameters are set based on unload state when the system in voltage loop and short-circuit state in current loop, it maximally improves the system steady and dynamic performance, especially, it reduces the excessive short-circuit current. Simulation and experiment verifies the results.