Analysis and Research on Short-circuit Capability of Transformer in Power System Series Compensation Test

Series compensation can shorten the electrical distance of the line and improve the power transmission capacity of the sending power grid. At the same time, due to the strengthening of the grid structure, the system's equivalent reactance is reduced, and the short-circuit current is increased, posing a threat to the operation of electrical equipment. The short-circuit resistance of power transformers is one of the important indicators to measure the safety performance of transformers. In this paper, setting a short-circuit fault at the first and the end of the series-compensated line, the short-circuit current passing through the main transformer is calculated, and the ability of the transformer to withstand short-circuit is checked by comparing with the design capability value. Analyze the influence of different operation modes on the main transformer crossing current, and propose the operation scheme of reducing the short-circuit current with the sending power grid of series compensation, pointing out the method of adopting the series compensation to promote the sending risk and avoidance of sending capacity, which have a certain guiding significance for the series compensation planning and operation of the sending power grid.