Page - 338 - in Emerging Technologies for Electric and Hybrid Vehicles

Energies 2017,10, 315 coil’spowerwas lostat±4cm,andnearlyallof itspowerwas lostat±8cm.Theresults inFigure20 verify the theoryexplainedinSection2,andthus, justify theneedfor theproposedACASsystem. Figure 20. Voltage and currentmeasured at the load, and its calculated power (first experiment: static load). Figure 21 shows the voltagewaveforms of the load coil and the sensor coilmeasured from the oscilloscope. Figure 21a,b representwhen the load coil has a leftmisalignment, and a right misalignment, respectively. Thecapturedresults indicate that significantnoise ispresent in thesensor coilwaveform. Thesearefilteredout througha low-passfilterbeforebeingconverted intoa logic signal as shown in the circuit schematic in Figure 19. Based on the results shown in Figure 21a, thephasedifferencebetweenthe loadcoilandsensorcoil is118.9degrees (leftmisalignment),while thephasedifference inFigure21b is−57.3degrees (rightmisalignment). Thedifferencebetweenthe tworecordedphasevalues is176.2degrees,which isnear the180phaseangledifferencedescribed in the lastparagraphinSection3.1. (a) (b) Figure21.Oscilloscopereadings fromthefirstexperimentshowingthevoltagewaveformof the load coilandthesensorcoilunitat (a) leftmisalignment;and(b) rightmisalignment. 4.3. ExperimentalResults fromtheSecondExperiment (Load: ExperimentalVehicle) The recorded load coil and sensor coil waveforms for the second experiment are shown in Figure22. Theseresults showcharacteristics similar to theresults showninFigure21, except there isa lowervoltageamplitude,because thesourcecoilwasoperatingata10Wpower level. Basedon the recordeddata, thephaseof the sensor coil relative to the loadcoil for the left side (Figure22a) 338