TY - JOUR
T1 - Analysis and Modeling of Circulating Current in Two Parallel-Connected Inverters
AU - Maheshwari, Ram Krishan
AU - Gohil, Ghanshyamsinh Vijaysinh
AU - Bede, Lorand
AU - Munk-Nielsen, Stig
PY - 2015/7
Y1 - 2015/7
N2 - Parallel-connected inverters are gaining attention for high power applications because of the limited power handling capability of the power modules. Moreover, the parallel-connected inverters may have low total harmonic distortion of the ac current if they are operated with the interleaved pulse-width modulation (PWM). However, the interleaved PWM causes a circulating current between the inverters, which in turn causes additional losses. A model describing the dynamics of the circulating current is presented in this study which shows that the circulating current depends on the common-mode voltage. Using this model, the circulating current between two parallel-connected inverters is analysed in this study. The peak and root mean square (rms) values of the normalised circulating current are calculated for different PWM methods, which makes this analysis a valuable tool to design a filter for the circulating current. The peak and rms values of the circulating current are plotted for different PWM methods, and a discontinuous PWM is identified which offers the minimum peak and rms value of the circulating current. Experimental results are presented to verify the analysis.
AB - Parallel-connected inverters are gaining attention for high power applications because of the limited power handling capability of the power modules. Moreover, the parallel-connected inverters may have low total harmonic distortion of the ac current if they are operated with the interleaved pulse-width modulation (PWM). However, the interleaved PWM causes a circulating current between the inverters, which in turn causes additional losses. A model describing the dynamics of the circulating current is presented in this study which shows that the circulating current depends on the common-mode voltage. Using this model, the circulating current between two parallel-connected inverters is analysed in this study. The peak and root mean square (rms) values of the normalised circulating current are calculated for different PWM methods, which makes this analysis a valuable tool to design a filter for the circulating current. The peak and rms values of the circulating current are plotted for different PWM methods, and a discontinuous PWM is identified which offers the minimum peak and rms value of the circulating current. Experimental results are presented to verify the analysis.
KW - Parallel inverters
KW - parallel interleaved inverters
KW - parallel interleaved converters
KW - Modulation scheme
KW - Phase-shifted carrier-based pulsewidth modulation (PSC-PWM)
KW - circulating current
KW - circulating current suppression
KW - common mode circulating current
KW - circulating current control
KW - Circulating Current
U2 - 10.1049/iet-pel.2014.0656
DO - 10.1049/iet-pel.2014.0656
M3 - Journal article
SN - 1755-4535
VL - 8
SP - 1273
EP - 1283
JO - IET Power Electronics
JF - IET Power Electronics
IS - 7
ER -