Hybridization power electronics

Chen J, Che Y, Zhao L. Design and research of off-grid wind-solar hybrid power generation systems. In 4th International Conference on Power Electronics Systems and Applications (PESA) 8-10 June 2011 Hong Kong IEEE pp. 1-5. DOLIO. 1109/PESA. 2011.5982922. 

In Chap. 8, fault scenarios in small switched power electronic systems are studied for illustration. The bond graph model-based approach to FDI in hybrid systems is, however, not limited to this kind of systems. 

The previous chapters address various aspects of quantitative bond graph-based FDI and system mode identification for systems represented by a hybrid model. This chapter illustrates applications of the presented methods by means of a number of small case studies. The examples chosen are widely used switched power electronic systems. Various kinds of electronic power converters, e.g. buck- or boost converters, or DC to AC converters are used in a variety of applications such as DC power supplies for electronic equipment, battery chargers, motor drives, or high voltage direct current transmission line systems [1]. 

Clearly, a bond graph approach to FDI of systems modelled as a hybrid system is not limited to switched power electronic systems but may be applied to other engineering systems as well for which a hybrid model is appropriate. In the following, the case studies consider faults in a DC to DC boost-converter, in a three-phase DC to AC inverter and in a three-phase rectifier AC to DC. In some motor drives, a rectifier and an inverter are used back-to-back [8], Computations have been performed by means of the open source software program Scilab [21],... 

The power switches suggest to capture the dynamic behaviour of a three-phase inverter by a hybrid model and to study the effect of switch failures on the behaviour of this type of power converter. Three-phase inverters are a common component in many power electronic systems. They are used, for instance,... 

Power electronic subsystems are widely used in a variety of electromechanical systems including motor drives with a mechanical load. They are built up by means of semiconductor switches that are commonly operated at high frequency. Their failure quite often give rise to faults in power electronic systems. For these reasons, mechatronic systems using power converters are well suited for an application of a bond graph model-based approach to FDI of system represented by a hybrid model. 

The book briefly recalls various bond graph representations of hybrid system models proposed in the literature. The development of hybrid models for the purpose of fault detection and isolation, in this book, makes use of conceptual nonideal switches representing devices for which it is justified to abstract their fast state transitions into instantaneous discrete state switches and accounts for stmctural model changes by special sources that are switched on or off at the advent of a discrete event. As other possible approaches, this approach has its pros and cons. For illustration, the presented method is applied in a number of elaborated case studies that consider fault scenarios for switched power electronic systems that are commonly used in a variety of applications. Power electronic systems have been chosen because they may be appropriately described by a hybrid model and are well suited for application of the presented bond graph model-based approach to fault detection and isolation. The approach, however, is not limited to this kind of systems. 

Kim I (2008) Nonlinear state of charge estimator for hybrid electric vehicle battery. IEEE Trans Power Electron 23 2027-2034. doi 10.1109/TPEL.2008.924629... 

Over the past two decades, compliance with stricter environmental requirements led to the rapid penetration of hybrid electric buses (HEBs)/EBs in urban transit bus fleets to improve fuel efficiency by 20-50% and, correspondingly, reduce exhaust emissions. Advanced technologies (lightweight materials for body, chassis, and seat assemblies stop-start systems for idle reduction improved batteries electric motors converters and power electronics) are also being deployed to further improve the fuel efficiency of advanced buses and urban air quality. 

The ongoing American Fuel Cell Bus (AFCB) project (discussed in Section 3.2.1) will demonstrate an improved ISE electric traction and power electronics system, featuring UTC FCs (120 kW) and the compact high-power EnerDel OB, in a lighter and quieter New Flyer 40-foot bus. This FCB architecture was deployed in 20 FC hybrid buses for the Vancouver 2010 Winter Olympics and has also been used for the London 2012 Summer Olympics. 

The optimum energy management of the vehicle and its components is one of the primary challenges of fuel cell hybrid electric vehicles. The difficulties result from the high nonlinearity of the control path (fuel cell, power electronics, battery, and electric machine) and subsequently the complexity of the control architecture. 

In active fuel-cell hybrid systems, the coupling between fuel cell and energy storage system is done via power electronic devices. The main elements are DC-DC converters. The following basic types exist [26] ... 

Gho, H.Y., Gao, W., and Ginn, H.L. (2004) A new power control strategy for hybrid fuel cell vehicles. Presented at the 8th IEEE Workshop on Power Electronics in Transportation, Detroit, October 2004. 

In most cases, successful hybridization of two or more power sources is expected to prolong the cycle life of a resulting systan since each component performs at the power and/or energy conditions that are close to their respective optimum range. The best utilization of a hybrid system is often assured by the sophisticated hybrid electronic battery management system (BMS) much work has been done on simplifying the BMS for the emerging hybrid power systems [1, 11-15]. Even with the current improvements, the need for a DC/DC converter to link the hybrid components to the power bus still contributes to mass, value, Ufe, and cost analysis of the hybrid system and presents an opportunity for improvement. 

Gao L (2005) Power enhancement of an actively controlled battery/utracapacitor hybrid. IEEE Trans. Power Electron 20 236-243. doi 10.1109/TPEL.2004.839784... 

Jiang ZH, Dougal RA (2006) A compact digitally controlled fuel cell/battery hybrid power source. IEEE Trans Ind Electron 53 1094-1104. doi 10.1109/TIE.2006.878324... 

From Husain, I., Power electronics and motor drives, in Electric and Hybrid Vehicles Design Fundamentals, CRC Press, Boca Raton, PL, 2003, p. 165. 

Various architectures for hybridized fuel cell-supercapacitor systems. Source Turpin, C. and S. Astier. 2007. IEEE Transactions on Power Electronics, 33,474 79. With permission.)... 

Dougal, R. A., S. Liu, and R. White. 2002. Power and life extension of battery-ultracapacitor hybrids. IEEE Transactions on Power Electronics, 25,120-131. 

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