Experimental Study of the Parameter Mismatch Effects on the Low Frequency Circulating Currents of Parallel Three Phase Inverters
Marian Liberos,
Raúl González-Medina,
Iván Patrao,
Enric Torán,
Gabriel Garcerá,
Emilio Figueres
Affiliations
Marian Liberos
Grupo de Sistemas Electrónicos Industriales del Departamento de Ingeniería Electrónica, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
Raúl González-Medina
Grupo de Sistemas Electrónicos Industriales del Departamento de Ingeniería Electrónica, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
Iván Patrao
Grupo de Sistemas Electrónicos Industriales del Departamento de Ingeniería Electrónica, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
Enric Torán
Grupo de Sistemas Electrónicos Industriales del Departamento de Ingeniería Electrónica, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
Gabriel Garcerá
Grupo de Sistemas Electrónicos Industriales del Departamento de Ingeniería Electrónica, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
Emilio Figueres
Grupo de Sistemas Electrónicos Industriales del Departamento de Ingeniería Electrónica, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
When converters are connected in parallel, a system with some benefits, including modularity and redundancy, is obtained. However, in these circumstances, circulating currents can appear that produce some adverse effects. In this work, a study of the low-frequency circulating currents that appear in three-phase inverters connected in parallel is performed. The study is focused on the effects produced by the parameter mismatch, namely inductance mismatches, power imbalance, and the use of different pulse with modulation (PWM) techniques. The nature of the circulating current produced by each of these factors were analyzed separately. Both simulation and experimental results are shown, which were obtained using a three-phase 10-kW prototype composed of two 5-kW inverters connected in parallel.
