Page - 334 - in Emerging Technologies for Electric and Hybrid Vehicles

Energies 2017,10, 315 It consistsofavoltagecomparator, exclusiveOR(XOR)gate,anddigitalvoltmeter. The loadcoil waveformandthesensorcoilwaveformareeachconverted into logicsquarewaveformsthroughthe voltagecomparatorsas shownin theblockdiagraminFigure13. Fromhere, the convertedsensor coil logicsignal,Vse′, andtheconverted loadcoil logicsignal,VL′ aresent into theXORgate,where the twosignalsarecomparedwitheachother todeterminethe leftor right lateralposition. Since the phaseof the loadcoil remainsunchanged, the loadcoilvoltage (inACform)canbeusedasareference todetermine thephasechange in thesensorcoil, as showninFigure9. The logicflowof theXORgate outputusedtodetermine the leftandrightposition is showninFigure14. TwoinputsignalsVse′, and VL′ aresentas input into theXORgate. Basedonthenatureofoperationof theXORgate, theoutput at theXORgate, expressedasLP, iseithera5Voutput (logicHI)ora0V(logicLO)signal to indicate leftor right, respectively. Figure14.TheXORgateoutput fromtheconverted loadcoilandthesensorcoil logicsignal inputs basedonleftor rightside lateralmisalignment. With the leftor rightsidedetected, the locationof the lateralmisalignment,y, canbedetermined as follows: y= { −f(VL) if LP=HI f(VL) if LP=LO (10) where f(VL) isa function that represents therelationshipbetweenthe loadcoilvoltageandthe lateral position,y.With theknownleft/rightposition, the lateralmisalignmenty isestimatedanddirectly fedas input into theACASfuzzysteeringcontroller. 3.3.ACASFuzzySteeringController The lateralmisalignment isestimatedbasedonthevoltagemeasurementalone,but irregularities canoccur in thereadingof theangularmisalignmentof the loadcoil,orevenbecauseof thenon-linear characteristics of theDWCsystem. In addition, the source coil used inDWCsystems is typically installed in segments tomaximize efficiency, asdescribed in [12,26]. Thus, it canbe expected that thevoltagesgenerated ineachsegmentwillnotbeentirely identical. To toleratesuchcharacteristics, a fuzzylogicbasedsteeringcontrolmethodisusedintheACAS,becauseitcanprovidebetterdynamic responsecomparedtootherconventionalcontrollers [27,28]. Thefuzzy logicsteeringcontrollerused for theACAS in this paperwaspreviously introducedby the authors. In thepresent study, only experiments toverify theperformanceof the fuzzysteeringcontrollerwereconducted. Thedesign processandsimulationresultscanbeobtainedin [24]. 4. ExperimentalValidation Toobserveandvalidate theoverallperformanceof theACAS,asmallerscaleDWCsystemand experimentalvehiclewereconstructed,andtwoexperimentswereconducted. In thefirstexperiment, 334