Page 86 - IJOCTA-15-4

Viet Thanh et al. / IJOCTA, Vol.15, No.4, pp.625-648 (2025)
other swarm algorithms, the ABC method can be- Circular No. 25/2016/TT-BCT, dated No-
come trapped in local optima rather than finding vember 30, 2016, from the Ministry of In-
the global optimum, leading to suboptimal BESS dustry and Trade of Vietnam, regulating
sizing. Additionally, the algorithm is highly sen- transmission power systems.
sitive to input parameters, and incorrect adjust- The remainder of this paper is organized as
ments can adversely affect the optimization re- follows: Section 2 presents the theoretical foun-
sults. Alsharif et al. 25 proposed an alternative dation of the problem and the basis for devel-
method for determining the size and placement oping the proposed method. Section 3 outlines
of the BESS to maintain frequency stability in re- the details of the proposed control strategy for
lation to system generation and demand was pro- the BESS. Section 4 provides an analysis and in-
posed. However, this method assumes the inter- terpretation of the simulation results for the test
nal resistance of the BESS and batteries to be systems used. Finally, Section 5 provides the con-
constant, whereas, in reality, these parameters clusion of this paper.
vary with SOC and temperature. Furthermore,
the method is only applicable to the IEEE 39-bus 2. Formulation of the problem
grid.
As discussed in some related works above, Figure 2 shows the generalized load frequency
the impact of uncertainties related to generation control for the power system in which the RESs
output, load, and intermittent generation sources and BESS are connected. The parameters are de-
has been considered. BESS devices are proposed noted as mathematical symbols and defined as fol-
is the generating power of the ith gener-
to improve frequency stability; however, exist- lows: P G i P
ing approaches mainly focus on determining op- ator G n , P L is the sum of load power, P BESS is
P
timal location and capacity. This article intro- the BESS power, H is the sum of the iner-
duces a new algorithm that utilizes voltage mag- tia constant of all rotating machines, including
nitude and phase set points through control loops, wind turbines, f ref is the reference frequency, f s
including frequency, voltage, reactive and active is the system frequency, D i is the nth droop coef-
powers, charge, and d- and q-axes current con- ficient of the ith generation system G i , H BESS is
trollers for the BESS. The proposed method im- the droop coefficient of the BESS, and P wind+PV
proves frequency stability and controls the power is the sum of the generated power of all RESs,
flow on inter-domain transmission lines under var- including the generated sources of wind and PV,
26,27
ious conditions and adverse situations in the grid and can be determined as follows in Equation
by integrating multiple RESs. From the authors’ (1):
perspective, this issue has not been fully ad-
1
dressed in the literature. The main contributions P wind+PV = ρA w v C p + ηA PV G
3
of this method are summarized as follows. 2 | {z } (1)
| {z }
P P V
(i) A detailed analysis of the impact of BESS P wind
in supporting frequency regulation in power where P wind is the wind power, P PV is the solar
systems with a high penetration rate of power, ρ is the air density, v is the wind speed, A w
RESs. is the swept area of the blades, C p is the power
(ii) Modeling the BESS as a storage system coefficient, η is the efficiency of the solar panel,
with a direct current (DC)/alternating cur- A PV is the area of the solar panel, and G is the
rent (AC) converter that can replace the solar irradiance.
existing synchronous generators to accom- The impact of RESs on the power system fre-
modate the increasing penetration of wind quency refers to the effects that variable RESs,
and PV units. such as wind and solar power, can have on the bal-
(iii) Proposing the BESS system to provide pri- ance between power generation and consumption
mary frequency control by supplying stored in an electrical grid. When the power output from
power to the grid during disturbances (such RESs fluctuates, it can cause variations in the grid
as cloud cover, generator tripping, or power frequency. This is because RESs like wind and so-
output shortages), while also acting as a lar power are intermittent and variable, meaning
secondary frequency controller by absorb- their output can change rapidly due to changes
ing excess power to reduce grid frequency in weather conditions. The impact of RESs on
and restore its initial energy level. power system frequency can be significant, par-
(iv) Proposing a solution to use BESS equip- ticularly if the grid is not designed to handle the
ment to improve frequency stability and en- variability of these sources. This impact can be
sure compliance with the conditions set by assessed as follows in Equation (2).
628