Modelling and Control of Parallel-Connected Transformerless Inverters for Large Photovoltaic Farms

[EN] This paper presents a control structure for transformerless photovoltaic inverters connected in parallel to manage photovoltaic fields in the MW range. Large photovoltaic farms are usually divided into several photovoltaic fields, each one of them managed by a centralized high power inverter. T...

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Detalles Bibliográficos
Autores: Liberos, Marian|||0000-0001-6574-1158, González-Medina, Raúl|||0000-0003-0378-5045, Garcerá, Gabriel|||0000-0002-5507-4379, Figueres Amorós, Emilio|||0000-0002-0716-3916
Tipo de recurso: artículo
Fecha de publicación:2017
País:España
Institución:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/98768
Acceso en línea:https://riunet.upv.es/handle/10251/98768
Access Level:acceso abierto
Palabra clave:Photovoltaic farms
Parallel inverters
Circulating current
Modeling and control
TECNOLOGIA ELECTRONICA
Descripción
Sumario:[EN] This paper presents a control structure for transformerless photovoltaic inverters connected in parallel to manage photovoltaic fields in the MW range. Large photovoltaic farms are usually divided into several photovoltaic fields, each one of them managed by a centralized high power inverter. The current tendency to build up centralized inverters in the MW range is the use of several transformerless inverters connected in parallel, a topology that provokes the appearance of significant zero-sequence circulating currents among inverters. To eliminate this inconvenience, this paper proposes a control structure that avoids the appearance of circulating currents by controlling the zero-sequence component of the inverters. A second contribution of the paper is the development of a model of n parallel-connected inverters. To validate the concept, the proposed control structure has been applied to a photovoltaic field of 2 MW managed by four 500 kW photovoltaic inverters connected in parallel.