Pulsed power transmission line transformer based on modern cable technology

A high-voltage transmission-line pulse transformer has been constructed based on modern cable technology. The transformer has been successfully tested for output powers of 0.5 GW. The high-voltage cable is equipped with a resistive layer (semicon) on the inner conductor and on the inside of the outer conductor. Semicon cables are commonly used in high-voltage transmission of electrical power. The pulse transformer was built using a coaxial semicon cable, with the inner conductor used as secondary winding and the screen as primary winding. Such a transmission-line transformer works in the same way as an ordinary transformer. The input is transformed to the desired output using a step-up or a step-down configuration. An output voltage of 85 kV with 1-μs duration was achieved into a 15 Ω load. Because the windings are coaxial the magnetic leakage is kept low and, therefore, the coupling coefficient is high. This type of transformer is useful in applications where weight is an important factor. Another advantage is the simple design and that it can be manufactured at a low cost.