台電系統低頻卸載策略之研究

Underfrequency Load Shedding Strategy Researching on Taipower System

李凌霄(Ling- Hsiao Li)

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(2008年)

摘要

台灣地形狹長，負載中心由北至南散佈，大型火力發電機組又集於中南部區域，台電系統自然形成為南至北長條型電力網路結構，南北輸電主要幹線延伸達三百多公里遠，而且又無鄰近的互聯電力系統以強化系統穩定度，所以當台電系統發生發電機跳機以及輸電線跳脫時，均會使系統頻率與電壓受到影響，發電機機組跳脫量大時更為明顯，為避免系統頻率下降過低而導致系統崩潰情形。因此必須運用低頻卸載策略，經過適當卸載後以遏止頻率過度的下降，避免系統崩潰造成全台停電。
本論文主要為利用電力系統模擬軟體PSS/E第29版，藉此模擬台電96、97、98年尖峰及離峰負載時，於各種預設事故下的系統頻率反應，再依據系統擾動的嚴重程度，以九十六年台電系統之卸載策略為根據執行卸載，使系統頻率回復至安全範圍為目的。經模擬分析後，96、97、98年尖離峰系統均可藉由台電96年之使用固定頻率式電驛卸載計畫，即成功卸載恢復系統穩定，期望能夠給調度人員做為參考依據。

關鍵字

電力系統穩定 ； 低頻卸載 ； 負載模型 ； 電力保護系統

並列摘要

Taiwan terrain is long and narrow, the load center spreads by the north to the south, the large-scale thermoelectricity generation unit the collection in the south central region, the Taiwan Telegraphic Transmission system naturally forms the from south to north of power network structure, the north to south electric transmission main extends reaches more than 300 kilometer far, moreover does not have the neighbor the interconnection electrical power system to strengthen the system stability, when the Taiwan Telegraphic Transmission phylogeny generator jumps and the transmission line isolate, it will cause the system frequency and the voltage comes under the influence, the generator unit isolate quantity is big when is more obvious, to avoid the system frequency dropping has lowered causes the system collapse situation, must therefore utilize the underfrequency load shedding strategy, after undergoing the suitable unloading, suppresses the frequency excessively The drop, avoids the system collapse creating the entire Taiwan power cut.
The main goal of this paper is using the simulation of the power system softwares of PSS/E 29 edition to simulate what kinds of changes will the system frequency responses in each presumable situation when Taiwan Telegraphic Transmission in the peak and the off-peak load in the year,96,97,and 98. Then, according to the system interference to do the load shedding based on Underfrequency Load Shedding Strategy Analysis of the Taipower System in 96, and makes the system frequency regain to the safe range. After this simulation and analysis, the peak and the off-peak load system in 96, 97, and 98 will can do the load shedding successfully and regain to the generally situation by using Underfrequency Load Shedding Strategy. Wish this thesis can be the useful basis for the dispatchers.

並列關鍵字

Power System Stability ； Underfrequency Load Shedding ； Load Models ； Power Protection System

參考文獻

[4] H. E. Lokay and V. Burtnyk, ‘‘Application of Underfrequency Relays for Automatic Load Shedding,’’ IEEE Transactions on Power Apparatus and System, Vol. PAS-87, No. 3, March 1968, pp. 776-782.

[5] L. Zhang, J. Zhong, ‘‘UFLS Design by Using f and Integrating df/dt, ” Power Systems Conference and Exposition, 2006 IEEE /PES, No. 1, Oct. 2006, pp. 1840-1844.

[6] V. N. Chuvychin, N. S. Gurov, S. S. Venkata, R. E. Brown, “An Adaptive Approach to Load Shedding and Spinning Reserve Control During Underfrequency Conditions,” IEEE Transaction on Power System, Vol. 11, No. 4, Nov. 1996, pp. 1805-1810.

[7] Daniel Kottick, Ofer Or, “Neural-Networks for Predicting the Operation of an Under-Frequency Load Shedding System,” IEEE Transactions on Power System, Vol. 11, No. 3, Aug. 1996, pp. 1350-1358.

[8] P. M. Anderson and M. Mirheydar, “An Adaptive Method for Setting Underfrequency Load Shedding Relays,” IEEE Transactions on Power System, Vol. 7, No. 2, May 1992, pp. 647-652.