最佳重構和電容器放置是兩種最常用來減少放射型配電網路中電力耗損的方法，以及能在各種條件限制之下，例如電壓、電流、電容和放射條件都受限的情況下，改善電壓。為同時解決這類型非線性離散最佳化的問題，本論文將提採用一智慧演算法，以期能將電力耗損降到最低。
本論文運用V型二元粒子群優化演算法(V-Shaped Binary Particle Swarm Optimization, V-Shaped BPSO)，藉由考慮兩個不同的速度映射族形獲得放射型配電網中的最佳功率損耗，從而解決了第一階段重構和電容器放置的問題。此一研究方法是利用二元字串來表示聯絡開關的狀態、電容器狀況和電容器尺寸。另外也利用懲罰運算法處理限制條件、極限過程驗算法來處理放射行條件並獲得可行的聯絡開關，亦修改以網絡拓撲為基礎的電力潮流方法以計算電流並確定網絡中的電耗。
本論文所提出的演算法已透過MATLAB©進行模擬，並使用兩種不同的IEEE基準系統中驗證(含IEEE 33和IEEE 69總線系統)，透過三個案例研究以分析本算法的有效性。第一個案例是在IEEE 33總線系統，包括五個不同的設計方案，方案一為最佳網路重構、方案五為同時最佳網路重構以及電容器放置，然後與文獻中的其他算法進行比較，所提出的算法顯示有明顯改善。第二個案例研究在IEEE 33總線系統網絡的四個不同位置模擬了四個不同的故障分析，這個想法是確定最佳的配電系統恢復計劃，將電容器安裝在固定節點，聯絡開關則是可調式，藉此提高電網彈性。最後一個案例是研究更大、更複雜的IEEE 69總線系統。

Optimal reconfiguration and capacitor placement methods are two of the most convenient alternatives to reduce power losses in a radial distribution network and improved voltage profile under various constraints such as voltage limits, current limits, capacitor limits, and radial conditions. To solve this kind of two nonlinear discrete optimization problems simultaneously, a much more intelligent algorithm needs to be employed to obtain an optimal solution.
Thus, this thesis employed an effective algorithm named V-Shaped Binary Particle Swarm Optimization (V-Shaped BPSO) to solve first stage reconfiguration and capacitor placement problems simultaneously by considering two families of velocity mapping functions. This proposed algorithm uses a binary string to represent the state of tie switches, capacitor conditions, and capacitor sizing. A penalty-based factor method was used to handle the power flow constraints and a limit process checking algorithm was used to handle the radial condition. A Network-Topology-Based Load Flow method (NTBLF) has been adapted and modified to calculate power flow and determine power losses in the network.
The proposed algorithm was simulated in MATLAB© environment and verified by using two different IEEE benchmark systems namely IEEE 33-bus and IEEE 69-bus systems. Three case studies were conducted. The first case study consists of five designed scenarios. The numerical results obtained for both scenarios one and five show enhanced performance when compared to other methods in literature in terms of power loss reduction and improved voltage profile. The second case study is on a distribution system restoration plan to improve grid resiliency. The last case study performed on a much bigger and more complex system. An inclusive discussion provided on the obtained results.

Table of contents
Thesis Validation Letter in Chinese……………………………………………i
Thesis Validation Letter in English…………………………………………….ii
Abstract (Chinese)………………………………………………………………….…...iii
Abstract (English)……………………………………………………………….……....v
Table of contents…………………………………………………………………........vi
List of figures…………………………………………………………...………...........x
List of Tables………………………………………………………………….…….........xii
List of Symbols…………………………………………………………………...........xiii
Chapter 1
Introduction
1.1 Introduction ……………………………………………………………………........1
1.2 Motivation…………………………………………………...……………….….....…3
1.3 Thesis objectives…………………………………………………………………...3
1.4 Thesis Methodology……………………………………………………...……....4
1.5 Thesis content organization…………………………………………………..5
Chapter 2
Literature Review
2.0 Introduction…………………………………………………………..……........……...........................................................................................................7
2.1 Basic structure of an electrical power system and radial distribution system……........................................................................7
2.2 Electric Power Distribution System………………………………………………....................................................................................................9
2.2.1 Radial Distribution system……………………………………………………......................................................................................................9
2.2.2 Loop Distribution system…………………………………………………….......................................................................................................10
2.2.3 Network Distribution system……………………………………...………......................................................................................................11
2.3 Power Flow Analysis………………………………………………...…………..............................................................................................................12
2.4 Distribution Network Reconfiguration for Power Loss Minimization and Voltage Profile Improvement…………………………………….13
2.5 Distribution Network Reconfiguration and optimal capacitor placement………..............................................................................15
2.6 literature review summary………………………………………………..........................................................................................................……...17
Chapter 3
Formulation of the Network Reconfiguration and capacitor placement problem
3.0 Introduction………………………………………………..………….………................................................................................................................….18
3.1 Problem formulation………………………………………………………............................................................................................................…….18
3.1.1 Line power flow equations……………………………………………....................................................................................................…….19
3.1.2 Simplified Distribution Flow Method…………………................................................................................................……………………20
3.2. Objective function……………………………………………………………............................................................................................................…..21
3.3 Constraint Handling …………………………………………………...........................................................................................................…………...23
3.3.1 Initialization algorithm………………………………………...………......................................................................................................…...23
3.3.2 constraint handling algorithm……………………………………...…….................................................................................................….25
3.3.2.1 limit check processing……………………………………………….....................................................................................................25
3.3.2.2 handling of power flow constraints…………………………………..............................................................................................26
3.4 Network-Topology-based Load Flow method…………………………………….............................................................................................26
3.5 Reconfiguration and Capacitor placement initialization for different scenarios…........................................................................29
Chapter 4
V-Shaped Binary Particle Swarm Optimization Algorithm
4.1 Introduction to Particle Swarm Optimization………………………………..............................................................................................…….31
4.2 Continuous particle swarm optimization………………………………………...............................................................................................….32
4.2.1 The general steps to implement PSO algorithm to solving an optimization problem are as follows……………………………..….35
4.3 Discrete Particle Swarm Optimization……………………………….………...................................................................................................….37
4.3.1 The general steps to implement the BPSO algorithm to solving an optimization problem are as follows…………………….….39
4.4 Mapping Family…………………………………………………...………….….................................................................................................................40
4.5 V-shaped-BPSO Reconfiguration and Capacitor placement swarm module….…...........................................................................42
4.5.1 Representation of Tie switches, Capacitor location, and size as particle…...........................................................................43
4.6 V-Shaped-BPSO- Reconfiguration and capacitor placement optimization module........................................................................45
Chapter 5
Simulation Results
5.1 Introduction…………………………………………………………..……......................................................................................................................…..47
5.2 IEEE 33 bus system test case I …………………………………………….......................................................................................................……...48
5.2.1 System data and one-line diagram………………………………………….....................................................................................................48
5.2.2: Performance comparison for various mapping family shapes……………...................................................................................49
5.2.3 Simulation Results for Case I……………………………………………...........................................................................................................51
5.2.4 Voltage profile improvement results for Scenario 1, 2, 3, 4, and 5………..................................................................................…53
5.2.5 Power Losses in the Branches for Scenario 1 and 5…………………........................................................................................……...58
5.3 Performance comparison with other methods………………………………….................................................................................................62
5.3.1 Comparison with other algorithms for 33 bus system with Scenario 1……..............................................................................62
5.3.2 Comparison with other algorithms for 33 bus system with Scenario 5.……...............................................................................63
5.4 IEEE 33 bus system test case II…………….……………………………………..........................................................................................................64
5.4.1 Optimal capacitor placement in radial distribution network considering reconfiguration………………...……………………………………..64
5.4.2 Simulation results in Case study II………………………………………......................................................................................................….67
5.5 IEEE 69 bus system test case III……………………………………………................................................................................................................71
5.5.1 System Data……………………………………...…………………………....................................................................................................................71
5.5.2V-shaped BPSO results for Scenario 1-Distribution network reconfiguration..............................................................................72
5.5.3 V-shaped BPSO results for Scenario 2-Distribution network reconfiguration and optimal placement of capacitor………………….74
Chapter 6
Conclusion
6.1 Conclusion ……………………………………………...………………………..........................................................................................................................77
6.2 Future works ……………………………………………………...…………….........................................................................................................................78
Reference
Reference…………………………………………………...…..................................................................................................................................................79

Appendix
Radial Distribution system test information………………………………………….........................................................................................................86
Figure A.1: Single line 33 IEEE Distribution test system………………………..................................................................................................…….86
Figure A.2: Single line 69 IEEE Distribution test system……………………………...................................................................................................87

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