- Time spent on interventions by equipment experts/piquet, JAPW Montreux Workshop 2024
How much time do equipment experts and piquets spend on remote and local interventions? Is there sufficient data available across the groups to do this analysis? What kind of data exists across the groups (what is logged?) and what would be needed in addition to extend the analysis? Can we quantify the potential gain from automating remote interventions? Can we differentiate between simple local interventions and more complex ones? Can this information be included in AFT or any other centralised tracking tool? What stan...
- T.F.Baumann, R.M.Garcia, K.Papastergiou, D.Peftitsis, Discharge-based Condition Monitoring for Electrolytic DC-link Capacitors, Transactions in Power Electronics, 2024
Electrolytic capacitors are among the most vulnerable components in power electronic converters, risking their efficient and electrically stable operation. This is due to the decreasing capacitance under long-term stress. Thus, monitoring of the capacitance is imperative for ensuring proper converter's operation. This paper proposes a low-invasive method for condition monitoring of the health-status of DC-link electrolytic capacitors. The proposed method is based on the estimation of the remaining capacitance by analyzing th...
- K.Haugen, K.Papastergiou, D.Peftitsis, Power Flow Control in a Modular Converter With Energy Storage, IET Power Electronics, 2024
Using modularized power converters with scalable energy storage in particle accelerators can be further enhanced with controls that can be adapted to optimise different design targets, such as to minimise the front-end stage peak current, the depth of discharge of electrolytic capacitors or the thermal cycling of semiconductors. This paper proposes a control system that is able to individually adjust the power flow of the converter modules under pre-defined load profiles, and hence separates the use of energy storage and gri...
- T.F.Baumann, K.Papastergiou, R.M.Garcia, D.Peftitsis, A condition monitoring method for solder layer degradation of liquid-cooled power semiconductors, PCIM Europe 2023
This paper presents a new method for condition monitoring of solder layer degradation of liquid-cooled power semiconductors. Solder layer degradation is detected by an increased thermal impedance, which has the effect that more heat is dissipated into the air instead of the cooling liquid. The proposed condition monitoring method is based on detecting the share of heat dissipated to the liquid and to the air. Experimental validation in a down-scaled laboratory setup is presented, with the focus for an application in an indus...
- K.Haugen, K.Papastergiou, D.Peftitsis, A scalable DC/DC converter topology with modularised energy storage for high energy physics applications
This paper presents the design and control of a high-power modular DC-DC converter for electromagnets used in high energy physics applications. The fundamental building modules, herein called bricks, can either be connected to the grid or to separate energy-storage components. The proposed modular converter enables independent power flow control among the bricks under control that is agnostic to mission profiles. In particular, the proposed converter design and control allow for independent control of currents delivered from...