Analysis of Black Start of a Microgrid with PV, DG, and BESS

Abstract

Different combinations of operating scenarios for a microgrid with distributed energy resources and energy storage system is considered to understand the operation of a microgrid. An operational strategy analysis of a microgrid system consisting of photovoltaics, diesel generator, and battery energy storage system during a black start in islanded mode is considered in this paper. BESS under study consists of a bidirectional converter and a battery system. BESS is assumed to be active as a solution provided in all the scenarios. The various capabilities of BESS in a microgrid system is also discussed. Microgrid system provides reliable power supply and hence black start capability for such a system is essential in keeping intact the advantages of a microgrid. Performing a black start requires a sequential process to be followed to avoid fluctuations in bus voltage, frequency, and protecting the fuses/ contactors from blowing. To black start the system under study, the DC breaker connecting the battery and the bidirectional converter needs to be closed. Closing the DC breaker results in high inrush current from batteries at the DC output of the bidirectional converter. A DC arrangement is envisaged in the battery energy storage system to avoid arcing due to high inrush current.

Grid black start-up scheme based on the large-scale new energy grid

“…At present, the regional power grid in our country has made the corresponding black-start plan according to its own network status and power distribution, and some have done black-start simulation tests [3][4]. In the black start scheme, the units with self-starting capabilities, such as water turbine units and gas turbine units, are generally selected.…”