- 學位論文
諧波對史考特變壓器差動保護的影響分析與模擬測試
The Effect Analysis and Simulation Test of Harmonics on Differential Protection for Scott Transformers
摘要
世界各國的高速鐵路（HSR）均以單相電源供給列車使用，大部份是採用三相對兩相的特殊接法變壓器來供電；由於列車的啟動、高速行駛、及煞車的用電量遽變，都會使馬達驅動電路產生大量的諧波，進而使電力系統的正弦波電壓和電流發生畸變造成電力品質不良並可能影響到保護電驛的正常功能。 史考特（Scott）變壓器為一特殊繞組結構之變壓器，其主要用途是將電力系統的三相電源轉換成平衡兩相或兩個單相電源供負載使用，由於負載可能含有大量的非線性設備，而使得電力系統中的諧波含量升高而影響電力品質。 本論文針對諧波對史考特變壓器差動電驛保護的影響加以分析探討，並以CA型差動電驛來做保護。在實驗部分是以ELGAR Smart Wave SW5250輸出正弦波及分別含到3次、5次、7次、9次諧波成份的電源，加入史考特變壓器差動保護系統來測試差動電驛始動時間變化情形。藉由本研究及實測之分析，期能提供有價值的參考依據作為差動電驛使用者設計保護協調之考量。
並列摘要
All of the High Speed Railway (HSR) systems around the world used single phase voltage to the trains, and adopted three-phase to two-phase special transformer to supply electric power. Due to the large variations of electric power when starting and braking the trains, there arises a lot of harmonics in the motor-driven system. And the nonlinear loads may cause a lot of harmonic, too. Scott transformer has a special wiring structure, it’s major purpose is to transfer a three-phase power source into a balance two-phase or two single phase power source for supplying special single plase loads. The research aims at the effects of harmonic to differential protecting relay of Scott transformer. The CA type differential relay is used to protect the Scott transformer. The instrument, ELGAR Smart Wave SW5250, is used to generate for the different waveforms this experiment. We hope the results can be a valuable reference for protection design for Scott transformer.