Serge Pittet

Design of a modular resonant converter for 25kV-8A DC power supply of RF cavities

This paper describes the design of an LCC resonant tank that is to be used in a 300kW modular power converter for an application in particle accelerators. The aim of the power supply is to provide a so-called RF cavity with 25kV DC and a current up to 8A. Modular approach is chosen for redundancy and availability. Each module is composed of a resonant tank with a step-up Medium Frequency Transformer with its secondary windings put is series. Full gain is ensured in the full operation frequency range considering component value inaccuracies and ageing of capacitors. The paper focusses on the design of the resonant tank and its implementation in a 100kW power module prototype.

Impact of Modularity and Redundancy in Optimising the Reliability of Power Systems that Include a Large Number of Power Converters

Abstract CERN is working on a new particle accelerator that will require a very large number of power converters. In that view, the reliability of the whole powering will be a major issue. The use of a redundancy and modularity may help increasing the overall machine availability. However, the reliability of the redundancy system must be high enough to add a significant improvement when compared to simple module systems. This paper suggests a comparative study of several modular and redundant configurations for optimising power converters reliability and draws some conclusion from what has been achieved in the LHC previous experience.

A modular 200kW-25kV DC medium frequency resonant converter for RF power amplifiers

This paper focuses on the study and the implementation of a 25kV / 200kW / 20kHz rectifier intended to supply radio frequency power amplifiers with a DC voltage in a precision range of 1000ppm. The topology is based on three LCC resonant modules, and the high voltage part uses three 100kW / 20kHz power transformers connected to 72 diode full-bridge rectifiers connected in series. The design of such transformers as well as the management of the voltage balancing between the rectifiers and between the modules constitute new challenges addressed in this paper. The key design points of the transformers are described. Then, a simulation based analysis presents the issues in balancing powers and voltages between the modules. All the presented results are validated by experimental measurements on a full scale system.

Modular resonant converter for 25kV-8A power supply: Design, implementation and real time simulation

This paper describes the design of a 300kW modular resonant power converter for an application in particle accelerators. The aim of the power supply is to provide a so-called RF cavity with 25kV DC voltage and a current up to 8A. Modular approach is chosen for redundancy and availability. Each module is composed of a resonant tank with a step-up MF transformer with its secondary windings put is series for reaching higher voltages. Full gain is ensured in the full operation frequency range considering component value inaccuracies and ageing of capacitors. The design of the resonant tank is detailed with its dimensioning and integration issues. Hardware in the loop validation of two control methods is done on one 100kW module to prepare experimental validation of a single module before implementing the full system.