High-current test-bench for thyristor-based semiconductors

Increasingly thyristor-based converters (e.g. FACTS) are being integrated in the grids, to stabilize the distribution and transmission grids, due to the high power handling-capability of these semiconductor devices. Nevertheless, during faults, these converters need to withstand high circulating currents without failing. To investigate these scenarios, this paper presents a test bench to simulate different failure modes in a controlled environment. This test bench is able to generate symmetrical and asymmetrical sinusoidal currents up to 20 kA with a maximum duration of two seconds. Directly after the high current event, the voltage blocking capability of the thyristor is tested, by measuring the leakage current of the device under test under high voltage conditions (DUT).