電力系統與離岸風場併接方法之研究

A Study on Methods of Connecting Offshore Wind Farm into Power Systems

潘建宏(Jian-Hong Pan)

指導教授 ： 陳昭榮

國立臺北科技大學/電資學院/電機工程系研究所/碩士(2011年)

https://doi.org/10.6841/NTUT.2011.00521

摘要

本文以彰化外海建置大型離岸風場為例，其總裝置容量假設為864 MW採型態C之風機裝置而成(單機容量為3.6 MW)，且以台電公司西元2015年系統為研究標的，探討電力系統與離岸風場之併接方法設計：(一)選擇161 kV匯流排線西H(5801)為併接位置且系統與風場間採集中式併入法(Single-Connection Method)；(二)選擇161 kV匯流排線西H(5801)與漢寶H(5817)為併接位置且系統與風場間採分散式併入法(Separate-Connection Method)；(三)選擇161 kV匯流排線西H(5801)與漢寶H(5817)為併接位置且系統與風場間採多併接點併入法(Multi-Connection Method)；(四)選擇345 kV匯流排彰濱E(2300)為併接位置且系統與風場間採集中式併入法。文中採用電力系統模擬軟體PSS/E 29版作為模擬工具，且依據台灣電力公司之「輸電系統規劃準則」與「再生能源發電系統併聯技術要點」規範進行各方面的模擬分析評估與檢驗模擬結果，模擬案例分析包括：穩態電力潮流分析、風場併入前後之匯流排電壓變動分析、最大三相短路故障電流、暫態穩定度分析、匯流排故障造成風場與系統解聯之臨界跳脫範圍以及臨界清除時間等對系統之衝擊詳細探討。
風場總容量864 MW併入系統後之模擬結果顯示：穩態電力潮流分析，正常系統線路滿載數量最少為併接方法四，因為其風場直接併接於345 kV，而不經過彰濱161 kV輸電線路；匯流排電壓變動分析，若風機採功率因數控制模式，則離峰統計結果，併接方法四其電壓變動範圍為-2.26%~2.10%，符合規範±2.5%之內；最大三相短路故障電流，因風場併接位置不同所以各匯流排的故障電流增益不同，比較彰濱E(2300)則併接方法四增益量最多，因風場直接引接於此；暫態穩定度分析，比較線西之電壓掉落幅度，離峰與尖峰統計結果，電壓掉落幅度最少皆為併接方法一，因為全部風場併於此匯流排，於故障發生時全部風機調節虛功率抑制電壓下降。比較線西之頻率擺動範圍，離峰與尖峰統計結果，以60 Hz為基準，併接方法四的頻率擺動範圍較為接近基準；臨界清除時間為暫態穩定度之指標，文中案例一為故障端彰濱E(2300)且跳脫彰濱E(2300)至中火南E(540)第一回線以及案例二為故障端彰濱E(2300)且跳脫彰濱E(2300)至全興E(2350)第一回線，模擬結果皆超過台電規範參考值兩倍，表示台灣電力系統非常強健。

關鍵字

大型離岸風場 ； 集中式併入法 ； 分散式併入法 ； 多併接點併入法 ； 電力系統模擬軟體

並列摘要

Focusing on the Changhua Offshore Wind Farm with an assumed total capacity of 864 MW generated by Type C wind turbines (each turbine equipped with a capacity of 3.6 MW), the study aims at examining and evaluating the methods of connecting the offshore wind farm into the Taipower 2015 power systems. There emerge accordingly four major connection scenarios under examination: (1). The Xian Xi 161 kV bus (H5801) is selected as the location for single-connection method; (2). The Xian Xi 161 kV bus (H5801) and Han Bao 161 KV bus (H5817) are selected as the locations for separate-connection method; (3). The H5801 and H5817 buses are selected as the locations for multi-connection method; and (4). The Zhang Bin 345 kV bus (E2300) is selected as the location for single-connection method. PSS/E 29 is adopted as the simulation tool, and the Taipower Distribution System Planning Guidelines and the Technical Rules of Renewable Energy Generation Connected to Taipower Transmission and Distribution System have been consulted for performing various simulations, analyses, and evaluations and for verifying the simulation results. Main issues analyzed and simulated include: steady-state power flow, bus voltage variation before and after the connection, maximum three-phase short circuit current, transient stability, the critical range of the tripping of the wind farm caused by bus fault, and the impact of critical fault clearance time on the power system.
As indicated by the results of simulating the connection of the wind farm with a total capacity of 864 MW into the main power system, analysing steady-state power flow. According to the statistics during the peak period, Scenario 4 reports the least number of overload lines. No line is under overload in Scenario 4 as the wind farm is directly connected through the Zhang Bin 345 kV bus, bypassing the 161 kV power transmission lines. In terms of bus voltage variation (analysis based on the premise that wind turbines are in the power factor control mode), the light statistics suggest that only Scenario 4 sustains a voltage variation of -2.26% to 2.10% that falls within the required range (±2.5%). In terms of maximum three-phase short circuit current, different connection locations result in different gains in short circuit current. When Zhang Bin E2300 is used for comparison, Scenario 4 betrays the most gain with a maximum three-phase short circuit current since the wind farm is entirely directly connected at this location. In terms of transient stability, when the degree of voltage drop at Xian Xi is compared, both the light and peak statistics identify Scenario 1 as the connection method with lowest voltage drop as the wind farm is entirely connected via the Xian Xi bus, and the wind turbines would regulate reactive power to curb voltage drop when fault takes place. On the other hand, when the amplitude of swing in frequency at Xian Xii is compared, both the light and peak figures indicate that Scenario 4 reports an amplitude of swing that is closest to the standard of 60 Hz. Critical fault clearance time is an indicator of transient stability. In examining the critical fault clearance time, the study simulates two different cases. In Case 1 in which a fault occurs at the Zhang Bin E2300 bus and leads to the tripping of the first circuit connecting Zhang Bi E2300 and Zhong Huo Nan E540,and in Case 2 in which a fault occurs at the Zhang Bin E2300 bus and triggers the tripping of the first circuit connecting Zhang Bin E2300 and Quan Xing E2350. All statistics results are more than two times of taipower standard, and it means taipower system is very strong.

並列關鍵字

Large-scale offshore wind farms ； Single-connection method ； Separate-connection method ； Multi-connection method ； Power system simulator for engineering

參考文獻

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