Flexible, Highly Dynamic, and Precise 30-kA Arbitrary Current Source

Abstract

High power current sources with high dynamic performance, ultra-low current ripple and absolute reference tracking accuracy are key elements for magnets (bumper, septum) that are used in accelerators. Similar requirements are also encountered in plasma research applications in fusion reactors as well as plasma research for future HVDC circuit breakers. There, the current source must be able to drive resistive/inductive and highly fluctuating loads without any compromise in its performance. In this paper, such a flexible, dynamic and accurate current source, able to provide amplitudes up to 30kA and bipolar voltages up to 10kV is introduced. The system's operating concept is presented and its design procedure in order to fulfill a list of demanding specifications is demonstrated. In addition, a detailed description of its near-optimal, advanced control system is presented. Finally, the theoretical considerations are verified by extensive simulation results for various operating scenarios, including driving chaotic arc loads.

Swiss competence center on energy research FURIES - Overview and contributions in the area of power electronics and SmartGrids

“…DC arc), a flexible, modular high current source based on a 3-phase interleaved buck converter has been successfully demonstrated at 3 kV and 3 kA [22], [23]. Based on this, a novel topology with series or parallel stack modules for higher requirements has been introduced in [24], further improved in [25]. Fig.…”

Field Bus for Data Exchange and Control of Modular Power Electronic Systems with High Synchronisation Accuracy of ±4 ns

“…Due to the typically rather low switching frequency in MMC applications, the requirements concerning the synchronisation accuracy and the communication delay are less demanding. Nevertheless, for systems with higher switching frequencies (13) , the synchronisation accuracy must be much higher. For example, a switching frequency of 100 kHz with the same duty cycle precision (10 bit) would result in a required accuracy of 9.5 ns.…”

Evaluation of Current Control Structures for Multi-Phase Interleaved DC-DC Converters

“…High bandwidth and precise current sources with the ability to deliver step-like as well as arbitrary/controllable current waveforms are emerging nowadays, finding a broad spectrum of applications, such as power hardware-in-the-loop (P-HiL) simulations [1]- [3], driving accelerator magnets for medical and fusion energy applications [4]- [7] or testing equipment for HVDC grids [8], [9]. The specifications for these applications are ever increasing, as they often require a high current rating, with a high dynamic (i.e.…”

“…It should be observed that the two-level bucktype topology might not be the most efficient topology for the whole output voltage range that needs to be served (measured efficiency surpasses 98% for v c of 550V but is lower than 95% for v c lower than 50V at nominal current). However, efficiency and power density are rather secondary goals for the aforementioned applications, where high dynamic performance, low ripple and high modularity are considered primary goals [9]. Note also that due to the high effective switching frequency and the ripple cancellation that is ensured by the interleaved operation, a rather low output capacitance is used.…”