App-based Tool for Automatic Controller Parameters Assessment for Power Converters in Particle Accelerator Facilities

Abstract

Regulation coefficients assessment in a particle accelerator power conversion system depends on the topology, the magnet and the desired transient response. The series/parallel combination of a generic power converter (a brick) to develop a larger one (e.g., the SIRIUS power converter family developed at CERN) allows to feed several magnets with different parameters. Then, such standardization allows to develop a control platform and associated regulation system that is common to all the possible configurations. Regardless of the clear flexibility, the commissioning of these converters faces some drawbacks, like the large amount of coefficient sets and the tuning performed for different workers: this leads to certain inconsistency and spread in the transient responses obtained, which is coherent with the inherent subjectivity of the adopted approach. In this work, a methodology for automatic identification of regulator coefficients is developed. From the definition of a desired time transient response, the method uses the response to a step voltage test to evaluate some figures of merit and the particle swarm technique to change the coefficients accordingly to the error obtained. A MATLAB-based app to implement the method in a user-friendly environment is developed. Experimental results based on a 400 kW prototype validate the proposal.