Proactive Modeling for Optimal Mitigation and Utilization of Common-Mode Behavior
Abstract
The Integrated Power and Energy System (IPES) of future naval vessels will ideally be able to supply the projected mission loads of" advanced radar and weapon systems while maintaining the mobility of the vessel. Yet, significant improvements in power density of p"ower electronic systems must be realized for this vision to come to fruition. It is expected that the greatest gains in power density will be achieved through improvements in the wide-bandgap (WBG)-based converters that will be ubiquitous in the Power Electronic P"ower Distribution System (PEPDS). However, the voltage slew rates and high-frequency switching of WBG devices generate significant e"lectromagnetic interference (EMI) [and common-mode (CM) behavior in particular] necessitatingincreased filtering/EMI suppression. The need for additional EMI suppression works against the power density improvements offered by WBG-based converters and therefore should ideally be kept to a minimum.The objective of the proposed line of work is to enable the optimal suppression of EMI at a minimum cost from the perspective of the IPES as a whole. A further aim is to utilize the information contained within acceptable levels of CM current for purposes of monitoring and control. A precondition to fulfilling these stated objectives is the fundamental abili"ty to quantify such behavior resulting from the actions and interactions of multiple converters in a large-scale, interconnected sys""tem such as PEPDS. To this end, a systematic approach was recently derived to construct CM equivalent models of complex power system"s directly from their respective mixedmode models. This approach was validated through application to the Purdue Reduced-Scale Naval DC Microgrid. Further development of the modeling approach is needed to broaden its application to transient and unbalanced conditi"ons, wherein there exists strong common-modedifferential-mode (DM) coupling.It is expected that the proposed modeling efforts wil"l provide the Navy with an enhanced understanding and ability to quantify EMI at the system-level of the IPES. Design questions that" the proposed modeling developments could address include quantifying and locating the primary sources of ship hull currents, identi""fying system-level CM resonances and the parasitics that dominate them, coupling of CM noise into DM operation during system transie""nts and upsets, circulating currents through parallelized converters, the system-level effects ofCMchoke saturation, etc. Such insig""hts would provide guidance for specifying and/or updating EMI standards and interface requirements, which is particularly critical i""n the heightened-EMI environment of WBGbased power converters. Finally, the modeling approach can be applied toward productively uti"lizing CM behavior. Of particular interest herein are ground fault detection and location as well as machine winding health monitori"ng. Hence, the proposed efforts are divided into four tasks: (1) generalized decomposition ofDMand CM behavior and automated generat"ion of decomposedMM models; (2) second-order effects in CM modeling; (3) model-based fault detection and grounding; (4) on-line machine winding health monitoring.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 20, 2018
- Source ID
- N000141812156
Entities
People
- Aaron D. Brovont
Organizations
- Office of Naval Research
- United States Navy
- University of Alabama