A Direct Converter for High-Energy Physics Applications

• Published in: IEEE transactions on plasma science Vol. 37; no. 4; pp. 593 - 602
• Main Authors: Cook, D.J., Clare, J.C., Wheeler, P.W., Bland, M.J., Przybyla, J.S., Richardson, R.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.04.2009; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Amorphous materials; Applied sciences; Circuit protection; Circuit topology; Circuits; Converters; Convertors; Density; Direct current networks; Electric currents; Electrical engineering. Electrical power engineering; Electrical equipment; Electrical machines; Electrical power engineering; Exact sciences and technology; HF transformers; Laboratories; modulators; Physics; Plasma; Power electronics, power supplies; Power networks and lines; predictive control; Protection; Resonance; Resonant frequency; resonant-power conversion; Ripples; RLC circuits; Switching circuits; Topology; Transformer cores; Transformers; Transformers and inductors; Voltage; Weight reduction; Power converter; Direct convertor; Transformation ratio; resonant-power conversion; High density; Energy convertor; Direct current line; Resonant circuit; HF transformers; Energy density; Short circuit; Switching conditions; High energy; Resonant power convertors; High frequency; modulators; predictive control
• ISSN: 0093-3813; 1939-9375
• DOI: 10.1109/TPS.2009.2013626

This paper describes the development of a high-frequency resonant-power converter for high-energy physics (CW) applications. The proposed converter topology has been demonstrated by the construction of a laboratory demonstrator that produces 25 kV with less than 1% ripple at 1 A (25 kW). The converter is a direct converter topology operating without the use of a dc link, significantly reducing the size and weight of the converter and resulting in a relatively high-energy density converter. A high-frequency (20 kHz) resonant circuit is employed which provides inherent short-circuit protection of the converter from the output, while reducing the turns ratio of the transformer. The transformer is integrated into the resonant circuit and operates at the same frequency as the resonant circuit (20 kHz). To achieve high-frequency and high-flux operation of the transformer, an amorphous (nanocrystalline) core is used, further reducing the physical size of the converter. Use of the resonant circuit also allows for soft switching of the IGBTs. High-frequency operation allows for a reduction in size of both the transformer and output filters, thereby removing the need for operation with a crowbar. All of the techniques implemented in the prototype converter may be extended to higher voltage higher power systems.