PROGRAMA DE PÓS-GRADUAÇÃO EM ENGENHARIA ELÉTRICA (PPGEE)
UNIVERSIDADE FEDERAL DA PARAÍBA
- Phone
-
(83)32167857
News
Banca de DEFESA: PEDRO AQUINO DE ALCÂNTARA
Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE: PEDRO AQUINO DE ALCÂNTARA
DATA: 29/06/2023
HORA: 08:00
LOCAL: Videoconferência
TÍTULO: Anti-Windup and Load Shedding for Smooth Transitions in Multi-Loop Power Management Of Islanded Single Unit-Sourced Microgrids
PALAVRAS-CHAVES: Islanded Microgrid. Photovoltaic-Battery unit. Multi-loop Power Management. Grid-Forming Droop Control. Anti-windup. Load Shedding.
PÁGINAS: 92
GRANDE ÁREA: Engenharias
ÁREA: Engenharia Elétrica
RESUMO: The huge development of distributed generation (DG) systems and their insertion in
the main grid has made the concept of microgrids (MG) the target of much research.
Renewable energy sources (RES) like photovoltaic (PV) and wind systems represent a vast
part of DG units once they have been developed to replace non-clean energy sources. Still,
it has been a challenge to make possible RES operations in islanded MG environments,
especially those formed by PV systems. The intermittent behavior of RES and their lack of
power reserve have provoked many problems like voltage and frequency deviations. For this
reason, energy storage devices such as battery energy storage systems (BESS) represent
an important solution for power support in islanded systems due to their fast response
to outages. Several strategies have been studied to provide standalone MG environments
with power management for maintaining the balance between generation power and load
demand. However, critical situations where the MG is composed of only one generation
system have been little addressed. In these cases, the physical limitation of BESS instigates
crucial decisions for keeping the grid balance such as generation power curtailment, when
BESS charging limits are reached, and load-shedding, when it reaches discharging limits.
This work studies a multi-loop power management strategy for a three-phase islanded
MG formed by one PV/BESS-based generation unit with grid-forming droop control for
the Voltage Source Inverter (VSI), including a secondary frequency/voltage regulation
and Proportional-Resonant control loops. To better understand the unit behavior, the
operation is divided into states. The transition among the states is performed by the
multi-loop strategy whenever the BESS has reached any limit. However, it is extremely
necessary to ensure smooth state transitions in order to avoid harmful current and
voltage variations. As the strategy is based on Proportional-Integral controllers, the
physical limitation of the BESS may cause constant steady-state errors and consequently
integration windup. This problem is extremely undesirable, because it may cause decision
delays and/or undesired transients during the transition among operation states. This
work proposes the use of integration anti-windup techniques in important PI controllers
for improving state transitions. Two well-known anti-windup techniques are compared
in order to assess smoother behavior. In addition, this work provides an improved loadshedding strategy based on the unit DC-link voltage to keep the power balance in cases
of low generation power availability. The results showed that anti-windup methods are
essential to avoid undesired transients, decision delays, and current/voltage harmful
oscillations during operation state transitions. Two anti-windup methods were tested:
clamping and back-calculation. Both showed extremely satisfactory performances. However,
the back-calculation technique showed a better performance in a situation when the BESS
state-of-charge (SoC) has to be regulated. This technique presented a better response by
avoiding under and overshoots during the transitions. Finally, the work was developed
through Matlab/Simulink simulations.
MEMBROS DA BANCA:
Presidente - 1652514 - CAMILA MARA VITAL BARROS
Externo à Instituição - DANIEL BARBOSA
Externo à Instituição - LUCIANO SALES BARROS
Interno - 1972270 - YURI PERCY MOLINA RODRIGUEZ