Investigation of the Incomplete Phase Mode of a Power Transformer

The article considers the causes and consequences of sequential ferroresonance in electrical networks in incomplete-phase operation modes of a power transformer. Transformations of substitution circuits of electrical installations are presented to determine the values of capacitances that cause ferroresonance processes in the circuit. Physical models have been constructed to study the features of sequential ferroresonance. Waveforms and vector diagrams are presented that characterize the voltage increase at the disconnected phase of the transformer with its overturning. The peculiarities of changing the capacitance of the damaged connection in the ferroresonance mode are shown. Studies have been conducted for electrical networks with isolated and deafly grounded neutral.