3. Conclusions

A comprehensive methodology for the design of a wasted heat energy recovery system is given. The general approach is to model separately the single stages starting from physical characteristic and derivate the resulting design constraints. Starting from the characteristic of a thermoelectrical generator cell, the mathematical model and the equivalent electrical model are obtained; after this step it was possible to design the TEG pack. From this point the generator is considered a general input for the power converter. Different topologies are analyzed, and all the fundamental design steps are reported for a non-inverting buck-boost converter: as part of the design, a loss estimation analysis was carried out. The control system is described as nested control loops. Two maximum power point tracking algorithms

placed after the TEG. The operating point is fixed; the value of the resistance seen by the TEG is initialized at a wrong value, after some iteration; and according to the maximum power transfer theorem, the maximum power point is reached. During the steady-state operation, the resistance value continuously changes its value as

seen in Section 2.4.1.

Maximum point tracking.

Figure 22.

Figure 21.

Figure 23.

124

Wasted heat energy recovery system block diagram.

System transfer functions and controller transfer function.

Advanced Thermoelectric Materials for Energy Harvesting Applications

are presented illustrating their characteristics and peculiarity. A state-space averaging method is used to obtain the converter transfer function in order to design a proper controller. Finally, simulation results and converter efficiency are shown in the last section. There are many possible advancements in this field from hardware and software point of view: development of new thermoelectric cells; use of more efficient power devices, for example, Gan FETs, in order to increase frequency and reduce passive components; and, also, development of faster and more efficient control algorithm are only some examples.

References

[1] Yu C, Chau KT. Thermoelectric automotive waste heat energy recovery using maximum power point track. Energy Conversion and Management. 2009;50:1506-1512. DOI: 10.1016/

DOI: http://dx.doi.org/10.5772/intechopen.86232

Universities Power Engineering Conference. 2008. DOI: 10.1109/

K. Performance analysis of

converter with incremental

10.1016/j.esd.2017.01.003

ECCE.2012.6342530

[7] Twaha S, Zhu J, Yan Y, Li B, Huang

thermoelectric generator using dc-dc

conductance based maximum power point tracking. Energy for Sustainable Development. 2017;37:86-98. DOI:

[8] Montecucco A, Siviter J, Knox AR. Simple, fast and accurate maximum power point tracking converter for thermoelectric generators. In: 2012 IEEE Energy Conversion Congress and Exposition (ECCE). 2012. DOI: 10.1109/

[9] Lee JH, Bae H, Cho BH. Advanced incremental conductance MPPT algorithm with a variable step size. In:

[10] Liu B, Duan S, Liu F, Xu P. Analysis and improvement of maximum power point tracking algorithm based on incremental conductance method for photovoltaic array. In: 2007 7th International Conference on Power Electronics and Drive Systems. 2007. DOI: 10.1109/PEDS.2007.4487768

2006 12th International Power Electronics and Motion Control Conference. 2006. DOI: 10.1109/

EPEPEMC.2006.4778466

ICT.2002.1190358

Harnessing the Automotive Waste Heat with Thermoelectric Modules Using Maximum Power…

[2] Liu C, Chen P, Li K. A 500 W lowtemperature thermoelectric generator: Design and experimental study. International Journal of Hydrogen Energy. 2014;39:15497-15505. DOI: 10.1016/j.ijhydene.2014.07.163

[3] Ji D, Romagnoli A. Modelling and design of thermoelectric generator for waste heat recovery. In: ASME Proceedings 9th Symposia: Fluid Mechanics (Fundamental Issues and

[4] Esram T, Chapman PL. Comparison of photovoltaic array maximum power point tracking techniques. IEEE Transactions on Energy Conversion. June 2007;22(2):439-449. DOI: 10.1109/

[5] Nagayoshi H, Kajikawa T, Sugiyama T. Comparison of maximum power

[6] Laird I, Lovatt H, Savvides N, Lu D, Agelidis VG. Comparative study of maximum power point tracking algorithms for thermoelectric generators. In: 2008 Australasian

thermoelectric power generator. In: Twenty-First International Conference on Thermoelectrics (ICT '02). 2002. DOI: 10.1109/ICT.2002.1190358

Perspectives; Industrial and Environmental Applications); Multiphase Flow and Systems (Multiscale Methods; Noninvasive Measurements; Numerical Methods; Heat Transfer; Performance); Transport Phenomena (Clean Energy; Mixing; Manufacturing and Materials Processing); Turbulent Flows; V01BT22A002. 2016. DOI: 10.1115/

FEDSM2016-7833

TEC.2006.874230

127

point control methods for

j.enconman.2009.02.015
