(A) study on power quality in a 154kV distribution system interconnected with photovoltaic power generation

다국어 초록 (Multilingual Abstract)

This study analyzes the power quality and fault response characteristics of a 154 kV distribution system interconnected with photovoltaic (PV) power generation through simulation using EMTP/ATPDraw. The objective of this research is to evaluate the impact of PV integration on system stability, harmonic distortion, and fault ride-through (FRT) performance under various operating and fault conditions.
The research consists of two main modeling domains.
First, the PV generation system modeling considers multiple fault conditions, including DC-side short circuits, insulation failures, and partial shading–induced
hot spot phenomena.
Second, the 154 kV distribution network modeling reproduces the interconnection structure and power flow between the PV system and the main
grid.
The models were implemented in EMTP/ATPDraw, and simulations were conducted under different fault locations and types to assess the resulting power quality variations and fault impacts.
Furthermore, this study proposes several preventive measures, such as the installation of bypass diodes, the selection of appropriately rated anti-reverse current diodes, and fault prevention strategies for inverters and grid protection systems.
These measures are evaluated in terms of their effectiveness in mitigating voltage distortion, limiting current surges, and improving overall reliability.
The results of this research provide fundamental technical insights for establishing protection and power quality management frameworks in PV integrated distribution systems.
Moreover, the findings are expected to contribute to the development of practical protection strategies, thereby supporting safe and reliable operation of renewable energy–integrated networks.

국문 초록 (Abstract)

본 연구는 EMTP/ATPDraw 시뮬레이션을 활용하여 154 kV 배전계통에 연계된 태양광(PV) 발전시스템의 전력품질 및 고장응답 특성을 분석하였다.
연구의 목적은 다양한 운전 및 고장 조건에서 태양광 연계가 계통 안정성, 고조파 왜곡, FRT(Fault Ride-Through, 고장 관통 성능)에 미치는 영향을 평가하는 것이다.
연구는 두 가지 주요 모델링 영역으로 구성된다.
첫째, 태양광 발전 시스템 모델링에서는 DC측 단락, 절연 파괴, 부분 음영(Partial Shading)에 의한 핫스팟(Hot Spot) 현상 등 다양한 고장 조건을 고려하였다.
둘째, 154 kV 배전계통 모델링에서는 태양광 발전소와 계통 간의 연계 구조 및 전력 흐름을 재현하였다.
이 모델들은 EMTP/ATPDraw 환경에서 구현되었으며, 다양한 고장 위치 및 고장 형태에 따라 시뮬레이션을 수행하여 전력품질 변화와 고장 영향을 분석하였다.
또한 본 연구는 바이패스 다이오드(Bypass Diode)의 설치, 역류방지 다이오드의 정격 선정, 인버터 및 계통 보호장치의 고장 예방 대책 등을 제안하였다.
이러한 대책들은 전압 왜곡 완화, 과전류 억제, 전체 시스템 신뢰성 향상 측면에서 그 효과를 평가하였다.
연구 결과는 태양광 연계 배전계통의 보호 및 전력품질 관리 체계 수립을 위한 기본 기술적 통찰을 제공하며, 나아가 재생에너지 연계 계통의 안정적이고 신뢰성 있는 운영을 위한 실질적 보호 전략 수립에도 기여할 것으로 기대된다.

목차 (Table of Contents)

• Chpater 1. Introduction 1
• 1. Background Research 1
• 2. Research Objective 3
• 3. Research Contribution 5
• 4. Outline of Dissertation 7
• Chpater 2. Photovoltaic Power System Interconnection 9
• 1. Korean DER Interconnection Standards 9
• 2. International DER Interconnection Standards 12
• 3. Configuration of a Photovoltaic (PV) Generation System Research 15
• 4. Two Types of Faults in Photovoltaic (PV) Systems 18
• 5. Risk Assessment of Faults in Photovoltaic (PV) Systems 20
• 6. Interconnection Methods of Photovoltaic (PV) Systems 22
• Chpater 3. PV-Integrated Distribution Modeling Using EMTP/ATPDraw 26
• 1. Modeling of PV Power Generation System Using EMTP/ATPDraw 26
• 2. Modeling of 154kV Power System Using EMTP/ATPDraw 27
• Chpater 4. Characteristics and Power Quality Improvement of PV-Integrated Distribution Systems 36
• 1. Characteristics of PV-Integrated Distribution Systems 36
• 2. Power Quality Improvement of PV-Integrated Distribution Systems 37
• Chpater 5. Simulation Results and Analysis 38
• 1. Simulation Results and Analysis of the Photovoltaic Power Generation System Using EMTP/ATPDraw 38
• 2. Simulation Results and Analysis of 154kV Power System Using EMTP/ATPDraw 45
• 3. Protection Coordination and Power Quality Improvement Measures 50
• Chpater 6. Conclusions 53
• References 55
• Korean Abstract 57