Reactive power generation and control by thyristor circuits

Generally, static VAr generators function as variable reactances (capacitive or inductive impedances) or controllable ac current and voltage sources. This paper reviews possible methods of VAr generation and control by static thyristor circuits and describes new approaches in which power frequency changers (cycloconverters) are employed. Oscillographic recordings illustrate the operation and performance of practical systems, including a 35 MVAR arc furnace compensator.