Pulse frequency modulation LLC series resonant X-ray power supply

摘要

To broaden the output voltage adjustment range of the X-Ray high voltage dc power supply and to make control circuit simple, a high frequency high voltage X-ray power supply with full bridge LLC(FB-LLC) series resonant converter is proposed. FB-LLC series resonant, high voltage transformer and bipolar single-phase symmetrical voltage multiplier are used in the main circuit. The parameters of the main circuit are selected with FHA (first harmonic approximation) model. The correspondent control circuit is designed through simulation software. First get approximate open-loop transfer function of the main circuit with the aid of the simulation software, and then design adjustor parameters. The simulation results of the X-Ray power supply show that the output voltage can be adjusted continuously within 40kV∼120kV with rise time less than 2ms and ripple factor less than 2%.