Different short-circuit impedance calculation method of controllable reactor of transformer type

The short-circuit impedance calculation of CRT is especially important to the establishment of equivalent circuit and analysis of operating characteristics. The paper reveals the intrinsic link between short-circuit impedance and equivalent circuit inductance by mathematical formula, and it elaborates three different methods to calculate short-circuit impedance, respectively the formula method, which calculates short-circuit impedance directly and easily; self and mutual impedance analytical method and ANSYS finite-element method, which calculate short-circuit impedance through the self and mutual inductance indirectly and have no geometric space restrictions to the windings. Then, an example is given to show that the results of these three methods are consistent, so these methods can be rationally chosen according to their own characteristics and the actual situation.