Reversible AC Drive Systems Based on Parallel AC-AC DC-Link Converters

In this paper, two reversible single-phase to three-phase ac drive systems are proposed. They are composed of a single induction motor fed by two parallel single- phase to three-phase dc-link converters without isolation transformers. For sake of generalization a configuration composed of three parallel single-phase to three-phase dc-link converters is also discussed. The proposed topologies permit to reduce the current and power ratings of the power switches when compared to the conventional single-phase to three-phase dc-link converter. Suitable modelling and control strategy of the systems based on odq approach, inclusive the unbalanced case, are developed. Simulated and experimental results are presented.