Impact current limiting circuit for sudden short circuit of transformer

The invention belongs to the technical field of anti-short-circuit tests of transformers, and particularly provides an impact current limiting circuit for sudden short circuit of a transformer. The circuit is composed of a single-phase rectifier transformer (1), a PWM rectifier H-bridge module (2), a discharge branch circuit (3), a low-frequency cascade H-bridge module (4), a high-frequency H-bridge module (5), a high-frequency connection reactor (6), a low-frequency connection reactor (7) and a system access point (8), wherein the high-frequency H-bridge module (5) generates harmonic current11-31 times, the low-frequency cascaded H-bridge module (4) generates harmonic voltage 2-10 times, and superposed output of the harmonic current is formed at the system access point (8) through the high-frequency connection reactor (6) and the low-frequency connection reactor (7). The circuit has the advantages that the generation range of harmonic current is remarkably expanded, the overall switching loss of the device i