Modulation Strategy to Reduce Common-Mode Voltage for Three-to-Five Phase Indirect Matrix Converter - Intelligent Computing for Sustainable Energy and Environment - page 35

100

80

60

40

20

0

-20

-40

-60

-80

-100

0 0.005 0.01 0.015 0.02 0.025 0.03

t/s

(a) The waveform of CMV before improvement

100

80

60

40

20

0

-20

-40

-60

-80

-100

0 0.005 0.01 0.015 0.02

t/s

(b) The waveform of CMV after improvement

Fig. 8. The waveform of common-mode voltage

of inverter stage: 60 V ,f =50 Hz . The switching frequency of inverter stage: f =
10 Hz . Five phase R load: R =10 Ω .
Fig.6 shows the simulation results of the rectifier stage. Since using the line-
to-line input voltage to synthesize the dc voltage, the output voltage waveform of
three-to-five phase IMC is different from the waveform of five-phase VSI, which
are shown in Fig.7.
Fig.8 shows the CMV waveforms with the conventional method and the im-
proved method. It can be seen that the peak value of CMV before improvement
is 100V. However, the peak value of CMV using improved method in inverter
stage is 86.6V, the common-mode voltage reduced significantly.

5Con lu on

In this paper, a novel space vector pulse modulation algorithm using four near-
est space vectors for three-to-five phase IMC is proposed. It provides the good
performance to validate the advantages of indirect matrix converter. However,
the common-mode voltage is unwanted for the proposed modulation. So the re-
lationship between the CMV and the switching states of IMC is clarified. By
suitable arranging the zero space vectors of the inverter stage, it successfully
reduces the CMV of IMC based on the zero dc-link current commutation. The
simulations are carried out to verify the theoretical analysis.

Acknowledgments. This work was supported by National Natural Science
Foundation of China(51107016).