Impedance measurement and detection frequency bandwidth, a valid island detection proposal for voltage controlled inverters

Anti-islanding detection methods have been part of a secure operation for distributed energy resource inverters, avoiding the creation of non-intentional energization when the mains are lost. These detection mechanisms were conceived historically for current-controlled inverters. New control possibi...

Descripción completa

Detalles Bibliográficos
Autores: Llonch Masachs, Marc|||0000-0003-1003-6720, Heredero Peris, Daniel|||0000-0002-6118-0928, Chillón Antón, Cristian, Montesinos Miracle, Daniel|||0000-0003-3983-0514, Villafafila Robles, Roberto|||0000-0003-4372-2575
Tipo de recurso: artículo
Fecha de publicación:2019
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/133269
Acceso en línea:https://hdl.handle.net/2117/133269
https://dx.doi.org/10.3390/app9061146
Access Level:acceso abierto
Palabra clave:Electric networks
Electric current converters
Anti-islanding
Voltage source converters
Impedance Measurement
Microgrids
Xarxes elèctriques
Convertidors de corrent elèctric
Àrees temàtiques de la UPC::Enginyeria elèctrica
Àrees temàtiques de la UPC::Energies::Energia elèctrica
Descripción
Sumario:Anti-islanding detection methods have been part of a secure operation for distributed energy resource inverters, avoiding the creation of non-intentional energization when the mains are lost. These detection mechanisms were conceived historically for current-controlled inverters. New control possibilities have broken ground, and current- or voltage-controlled inverters are a reality; however, special attention must be paid to detection strategies when applied to the latter ones. This paper addresses two topics: it exposes the lack of effectiveness of those detection algorithms based on the voltage/frequency displacement concept under voltage-controlled inverters and evaluates the applicability limits of the others based on the impedance measurement (IM). The IM is presented as a valid mechanism to achieve the islanding detection, but the exploration of its limits drives the concept of detection frequency bandwidth (DFBW), introduced in this paper. The DFBW is suggested as a practical approach to select the proper injection frequency to measure. Therefore, an improved strategy based on the IM and DFBW is proposed to allow achieving the detection towards (non-)resonant loads considering low computational burden. The results were experimentally validated in a 90-kVA four-wire voltage-controlled inverter, offering detection times of less than 100 ms in any case.