## 3 Comparison with the Experimental Results  
An experimental laboratory OLMEH prototype, as shown in Figure 1, and its power processing unit were built and tested. The OLMEH's core was constructed by stacking together three pairs of 10H10 C-cores made of silicon steel (EILOR MAGNETIC CORES). The magnetic path length was \(l_{c}=120\) mm, and the total core cross-section of \(A_{c}=1800\) mm\({}^{2}\). The total number of secondary turns was \(N=40\).  
NTP011N115 MC MOSFETs and Schottky rectifiers STP80H100 TV were used. The prototype controller was developed and built to allow for adjustment of the delay time, \(t_{1}\), and the controller's power transfer window width, \(t_{pw}\), independently.  
The Froelich parameters of the core \(a\) and \(b\) were established by curve fitting to the experimental data. Measured B-H characteristics of a silicon steel core sample vs. the fitted BH curve, drawn by using the extracted Froelich parameters, are shown in Figure 6. Here, \(a=2.05\) [T] and \(b=109.4\) [At/m] were found, the same as in [10].  
Typical waveforms of the experimental OLMEH with an active rectifier at line current \(I_{1}=100\) A rms under constant voltage load, \(V_{b}=45\) V, are shown in Figure 7. Here, the waveforms shown are: line current \(i_{1}(t)\), the rectifier input current \(i_{in}(t)\), and the gating signal of the M1 switch, \(v_{g}(t)\), generated by the controller. The math channel shows the instantaneous output power \(p_{o}(t)\). Recall that energy transfer to the high level of the \(v_{1}(t)\) waveform. Note that the primary voltage, \(v_{1}(t)\), was measured across the line conductor segment of only about 10 cm long. Also, it is worth noting that (during the positive half cycle), the saturation of the core manifests itself by the rapidly falling edge of the \(i_{in}(t)\) current. The energy stored by the magnetizing inductor manifests itself by the offset segment seen in the \(i_{in}(t)\) waveform, when the \(v_{1}(t)\) is at its zero level. The release of the stored energy is manifested by the down-going step in the \(i_{in}(t)\) waveform.  
Figure 6: Comparison of the measured BH curve of the silicon steel core sample (EILOR MAGNETIC CORES) to its Froeich approximation [10].  
Figure 7: _Cont._  
The theoretical derivations were first verified by simulation. Figure 8 shows the comparison of the calculated vs. the simulated results for the output power. Here, the assumed line current was \(I_{line}\) = 100 A rms and \(I_{line}\) = 200 A rms (also \(N\) = 40, \(V_{b}\) = 45 V). Good agreement between the results was found.  
Comparison of the experimentally measured vs. calculated by (33) and (27) output power as a function of the delay time \(t_{1}\), for line current \(I_{line}\) = 100 A rms and constant load voltage \(V_{b}\) = 45 V, as shown in Figure 9. A good match between the experimental and theoretically predicted power can be observed.  
Figure 8: Comparison of the simulated vs. calculated OLMEH’s output power as a function of the delay time, \(t_{1}\), for line current of \(I_{line}\) = 100 A rms and \(I_{line}\) = 200 A rms, (here, \(N\) = 40 and \(V_{b}\) = 45 V).  
Figure 7: Typical waveforms of the experimental OLMEH with an active rectifier at line current \(I_{1}\) = 100 A rms: \(V_{b}\) = 45 V. Delay time: (**a**) \(t_{1}\) = 1 mS; (**b**) \(t_{1}\) = 1.5 mS; (**c**) \(t_{1}\) = 2 mS; (**d**) \(t_{1}\) = 2.5 mS; (**e**) \(t_{1}\) = 3 mS; (**f**) \(t_{1}\) = 3.5 mS; (**g**) \(t_{1}\) = 4 mS.  
The experimental work revealed that handling the OLMEH prototype brought about variations in its magnetic properties, primarily due to variations in the technological air gap between the two halves of the C-core, which depend on factors like mounting force and surface imperfections. Therefore, some inaccuracies can be seen in the presented comparison plots.  
The view of the experimental prototype OLMEH and its test bench are shown in Figures 10a and 10b, respectively, and they are similar to that used in [10].