  Power system restoration is an important part of system planning. Power
utilities are required to maintain black start capable generators that can
energize the transmission system and provide cranking power to non-blackstart
capable generators. Traditionally, hydro and diesel units are used as black
start capable generators. With the increased penetration of bulk size solar
farms, inverter based generation can play an important role in faster and
parallel black start thus ensuring system can be brought back into service
without the conventional delays that can be expected with limited black start
generators. Inverter-based photovoltaic (PV) power plants have advantages that
are suitable for black start. This paper proposes the modeling, control, and
simulation of a grid-forming inverter-based PV-battery power plant that can be
used as a black start unit. The inverter control includes both primary and
secondary control loops to imitate the control of a conventional synchronous
machine. The proposed approach is verified using a test system modified from
the IEEE 9-bus system in the time-domain electromagnetic transient simulation
tool PSCAD. The simulation results shows voltage and frequency stability during
a multi-step black-start and network energization process.
