=Paper=
{{Paper
|id=Vol-1755/152-159
|storemode=property
|title=Impact of Passive Cell (PC) and Active Distributive Network Cell (ADNC) on Power System Oscillation
|pdfUrl=https://ceur-ws.org/Vol-1755/152-159.pdf
|volume=Vol-1755
|authors=John Oladosu,Abdrazak Olawoye
|dblpUrl=https://dblp.org/rec/conf/cori/OladosuO16
}}
==Impact of Passive Cell (PC) and Active Distributive Network Cell (ADNC) on Power System Oscillation==
https://ceur-ws.org/Vol-1755/152-159.pdf
Impact of Passive Cell (PC) and Active Distributive
Network Cell (ADNC) on Power System Oscillation
John B. Oladosu Abdrazak A. Olawoye
Department of Computer Science and Engineering, Department of Computer Science and Engineering,
Ladoke Akintola University of Technology, Ogbomoso, Ladoke Akintola University of Technology, Ogbomoso,
Nigeria Nigeria
Correspondence Authors (johnoladosu@gmail.com) aaolawoye@student.lautech.edu.ng
ABSTRACT Distribution Network Cell (ADNC) and to analyze the small and
Impact of Active Distribution Network Cell (ADNC) Study on large signal stability changes and to analyze the power flow
Power System Oscillation requires modelling of power system signal [1,7].
components. The system covers the well knows Two Areas-
System benchmark which studies low frequency electro-
2. METHODOLOGY
mechanical oscillations in large interconnected power system. Impact of Active Distribution Network Cell Study on Power
This study examined the effect of passive cell on Active System Oscillation requires modelling of power system
Distributive Network Cell (ADNC). The method adopted was components. The system covers the well knows Two Areas-
modelled using Power System Analysis Toolbox in MATLAB System benchmark. The benchmark is a model was created by
environment. The result was varied by analysizing the effect of Canadian Association to presents the various types of
passive cell at different position and Active Distributive oscillations that may happen in large/small power systems. It is
Network Cell (ADNC) at different positions. The damping also known as Kunder’s system which “is specifically designed
effect is also analyse through reactive and real (active) power to study low frequency electromechanical oscillations in large
profile. interconnected power systems” [1].
CCS Concepts 2.1 System Model
The 2-Area System was modelled using Power System Analysis
• General and reference ➝Cross-computing tools and
Toolbox (PSAT) embedded in Matlab Environment. Figure 1
techniques ➝Experimentation shows the design overview. The analysis of the system model is
summarized below:
Keywords
ADNC, Passive Cell, PSS i.) The System consists of two areas: Area I region is
indicated by the buses on the left half side of Figure 1
1. INTRODUCTION and Area II region is indicated by the buses on the
The types of load in modern power systems range “from simple right half.
resistive load to more complicated loads with electronic
controllers” [1-14]. Power system complexity and their ii.) The two areas are connected together by a
characteristic nonlinearity increase with increase in controllers transmission line of power, voltage rating and
and loads. This in turn makes power systems to exhibit frequency of 100MVA, 20kV and 60Hz respectively.
increasing instability problem. Power instability problems can iii.) The system generally consists of 4 PSSs, 4 AVRs, 5
cause partial or total blackout. This problems can be categorized Synchronous Generators, 3 PV Generators, 3 ZIP
into “voltage, phase angle and frequency related problems” [1- Loads, 3 PQ Constants, 11 Buses, 5 Transformers, 5
7]. transmission lines, 1 Slack Bus, and 1 Induction
In order to address power systems disturbances many devices Machine.
have been invented and a number of solutions have been iv.) Each of the Area consists of 2 Synchronous
proffered to enhance the effectiveness of these devices. These Generators, each of rating 900MVA of Power and
include fast exciter or Automatic Voltage Regulators (AVR), 20kV of Voltage.
Power System Stabilizer (PSS) which helps to produce the fine
adjustment needed to damp out electromechanical or low v.) Each generator is equipped with AVR and PSS.
frequency oscillations in power systems [1, 7-10]. Existing study vi.) The loads are applied at Bus 6 and Bus 5.
[1] examined the “Impact of Active Distribution Network Cell
(ADNC) on Power System Oscillation.” The objective of the vii.) The Slack Bus, PSS, AVR, Synchronous Generator,
work is to examined the impact of Passive Cell (PC) on Active Transformers, and Transmission Lines are all linked
together by Buses of rating 20kV.
CoRI’16, Sept 7–9, 2016, Ibadan, Nigeria.
152
Figure 1: The Two Area System (PSAT Implementation)
3. IMPLEMENTATION AND RESULTS
2.2 Design Approach
There are three cases considered in the system design, namely: 3.1 Base Case Analysis
Base Case, in which the system is considered neutrally as The base case load benchmark is P= 2734 MW, with 100 MW
depicted in Figure 1; Passive Cell (PC) Case and Active transferred from Area I to Area II over the tie-line. Results in
Distributive Network Cell (ADNC) which are varied at Bus 5 Figures 3 and 4 show the power flow and the eigenvalues for the
and Bus 6 as shown in Figure 2 (a) and 2 (b) respectively. base case system.
The system with passive network cell consists of Induction
Machine, constant PQ load and ZIP load.
Figure 2: (a)Passive Cell Figure 2:(b) ADNC Figure 3: Power flow curve
The Active Distributive Network Cell consists of the following:
ZIP Load, Back-to-Back Converter, Synchronous Generator and
Inductor Motor [1].
153
Figure 4: Eigenvalues diagram of Two Area System (Base Case)
3.2 System with Passive Cell (Loads and IM)
In order to study and analyze the impact of Passive Cell in the
Power System Oscillation, Passive Cells which consists of
Loads (ZIP and PQ) and Induction Machine are applied to the
system (Figure 5).
Figure 5: PSAT Implementation of the Study with Passive Cell
154
The power flow of system with PC at bus 6, Area II is as shown
in Figure 6. Figure 7 is the eigenvalues curve for the system
with PC.
Figure 8: Power flow analysis of the passive cell at Area I
Figure 6: Power Flow by the System with PC (Area II)
Figure 9: Eigenvalue report of passive cell at Area I
Figure 7: Eigenvalues report at Area II for system with PC
Figure 8 shows the power flow analysis of the system with PC 3.3 IMPLEMENTATION OF ADNC
implementation at Area I while Figure 9 is the eigenvalue for the Figure 10 represents the implementation of the two Area System
same system. of the study by replacing the Induction Machine as shown in
Figure 5 with Synchronous Machine. The ADNC consists of
Synchronous Machine, ZIP load and constant PQ load.
155
Figure 10: Power System with ADNC (PSAT Implementation)
Figure 11 is the power flow analysis of the implementation with
ADNC at Area II and Figure 12 is the eigenvalue.
Figure 12: Eigen value report of ADNC at Area II
Figure 11: Power flow of ADNC system at Area II
For implementation of the ADNC system at Area I, the power
flow analysis is shown in Figure 13 and the eigenvalue graph is
It can be seen from Figure 11 that power flow maximum shown in Figure 14
convergency error at bus 6 is the same as that for PC at Bus 6
(Figure 8).
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Table 1: Global Summary Report
Figure 13: Power flow in ADNC at Area I
4.1 Comparison between existing model and
new model
In term of the design model, when solving the power flow from
the existing design, there are errors generated, shown as follows:
Definition of system connections ...
Error: Block cannot be connected to block .
Error: Block cannot be connected to block .
Error: Block cannot be connected to block .
Figure 14: Eigenvalue report at Area I Error: Block cannot be connected to block .
***
Failed conversion from Simulink model: Simulink model is not
4. DISCUSSION well-formed (check links).
Table 1 shows the report of the Total Generation, Total Load
and Total Losses of both Real and Reactive Power of the model Attempted to access idx(2); index out of bounds because
for each of the cases i.e. base case, PC case and ADNC case. numel(idx)=1.
From the table, it can be seen that ADNC has a great impact on Data conversion failed.
power system oscillation than any of the other in term of the
total generation, total losses and total load of the model. These errors make the existing model heavily error-prone. The
errors are corrected using the new model by removing the
transmission lines (compare Figure 15 with Figure 16).
157
Figure 15: Existing model
Figure 16: New Model
158
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