Three-phase inverter parallel circulation control

Is there a circulating current control loop for parallel three-level inverters?

Shao et al. have developed a circulating current control loop for parallel three-level inverters when two distribution factors are introduced into the zero-sequence modulation function in order to eliminate the low-frequency circulating current and to control neutral point potential.

What are circulating current suppress strategies for parallel inverters?

Thus, the circulating current suppression becomes a key research problem for parallel inverters. In general, the circulating current suppress strategies can be categorized as hardware-based solutions, modulation-based solutions, and controller-based solutions.

Are the three-phase currents of each T-type inverter consistent and balanced?

It can be seen from Figs. 7 (b) and (c) that even the variation in the filters impedance value, the three-phase currents of each t-type inverter are consistent and balanced. These results validate the design and the effectiveness of the proposed circulating current controller. Figure 7 (d) displays the a-phase currents of each t-type inverter.

Does space vector modulation reduce circulating current in paralleled T-type inverters?

This paper provides an investment on the three-level Space vector modulation and proposes a new strategy to eliminating the circulating current for paralleled three-level t-type inverters. Results obtained confirmed the performance and the effectiveness of the proposed circulating current control strategy.

How circulating current affect inverter efficiency?

However, the circulating current results from the common connection of both AC and DC sides directly can increase the current stresses and conduction losses of the switching devices and reduces inverters efficiency.

How to suppress CMV and circulating current simultaneously?

To suppress the CMV and circulating current simultaneously, an improved control method is presented. At first, the discrete model of paralleled 3P2L inverters is established, based on which the improved control method is designed to restrain the circulating current, while the parameter tuning is avoided.