the analysis in Section III, the setup requires a high current injection from the current sources due to the relatively high leakage inductance and ESR of the transformers. Fig. 14 shows the experimentally obtained waveforms with and without the compensation current when the load current IL is 4.2 A. Fig. 15 shows the compensation currents is1 and is2 at the same load. The improvement of the line current harmonic level is apparent: The THD drops from 4.60% to
2.41%. The magnitude of each harmonic is plotted in Fig. 16. It is interesting to note that even the initial harmonics are fairly low and much lower than for the 12-pulse rectifier with LC
filter design for dc ripple minimization. This is due to the choice of the LC filter that amplifies the 360-Hz harmonic in the current. In Fig. 14, results show that the rectifier current is successfully shaped into the triangular form. Further comparisons are shown in Fig. 17, with different load conditions. Fig. 17 shows that the proposed method is effective at reducing the harmonics in the input line current even as the rectifier output current is becoming discontinuous. The VA rating of the current sources at different load conditions
is shown in Fig. 18. It can be seen that the optimized point (where the VA rating is minimized) is when the load current is 2.6 A (with load resistance as 25 Ω). On the other hand, according to (7) and (8) and Table II, the calculated optimal point is when the load resistance is 22 Ω. The VA rating is relatively high because of the high leakage inductance and ESR of the transformer. According to the current flow analysis described in the previous section, we can see that, for the filter parameters from Table II, only 57.1% and 56.1% of the
the analysis in Section III, the setup requires a high current injection from the current sources due to the relatively high leakage inductance and ESR of the transformers. Fig. 14 shows the experimentally obtained waveforms with and without the compensation current when the load current IL is 4.2 A. Fig. 15 shows the compensation currents is1 and is2 at the same load. The improvement of the line current harmonic level is apparent: The THD drops from 4.60% to
2.41%. The magnitude of each harmonic is plotted in Fig. 16. It is interesting to note that even the initial harmonics are fairly low and much lower than for the 12-pulse rectifier with LC
filter design for dc ripple minimization. This is due to the choice of the LC filter that amplifies the 360-Hz harmonic in the current. In Fig. 14, results show that the rectifier current is successfully shaped into the triangular form. Further comparisons are shown in Fig. 17, with different load conditions. Fig. 17 shows that the proposed method is effective at reducing the harmonics in the input line current even as the rectifier output current is becoming discontinuous. The VA rating of the current sources at different load conditions
is shown in Fig. 18. It can be seen that the optimized point (where the VA rating is minimized) is when the load current is 2.6 A (with load resistance as 25 Ω). On the other hand, according to (7) and (8) and Table II, the calculated optimal point is when the load resistance is 22 Ω. The VA rating is relatively high because of the high leakage inductance and ESR of the transformer. According to the current flow analysis described in the previous section, we can see that, for the filter parameters from Table II, only 57.1% and 56.1% of the
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