臺灣博碩士論文加值系統

本論文採用了同步偵測法，於主動濾波器中偵測及補償不平衡電源系統的
虛功及諧波電流。雖然瞬時功率理論在計算虛功及諧波電流的補償量時相
當有效，但僅能正確地使用在平衡的三相系統中。而在大部份實際的系統
中，特別是輻射狀配電系統饋線之末端，要維持供電系統的平衡是極困難
的。本論文提出的同步偵測法含等功率、等電流、等電阻等三種方式的同
步偵測法。經由模擬結果證實同步偵測法在不平衡電源系統中可得完美的
補償電流波形。文中亦重新導出了瞬時功率理論d-q軸上作功電流分量之
公式，並發現此公式和經由等電阻同步偵測法所得之結果完全相同。除了
傳統三相系統外本文亦將同步偵測法應用於多相系統，並且獲得令人滿意
的結果。最後並以實際負載為對象，將本同步偵測法應用於主動濾波器，
完成一組實際操作的實驗硬體。本法之優點即為採各相之分別計算，可避
免使用轉換矩陣引起 之誤差及波型惡化，而且電路簡單。由於使用了同
步偵測法，改進了主動濾波器補償虛功及諧波電流的性能，並具備能平衡
負載之功能。

This dissertation presents a new method, termed as the
synchronous detection method, for active power filter to
compensate the reactive and harmonic current in an unbalanced
three-phase power system. Although the instantaneous power
theory is powerful to operate an active filter, an assumption
of balanced three-phase source voltage is required. Due to
the inherent unbalanced characteristics in distribution feeder
system , the synchronous detection method is proposed here to
handle the unbalanced voltage to solve the reactive and
harmonic current compensation problem. Three alternative
methods using equal power , equal line current and equal
resistance concept of the synchronous detection method are
formulated. By simulation results, the performance of the
synchronous detection method is proven to be improved. In this
dissertation, results using the equal power, equal line
current and equal resistance synchronous detection methods are
shown. The d-q compensated component of instantaneous power
theory is modified and reformulated for an unbalanced system ,
and its result is proven to be the same as that of equal
resistance synchronous detection method. The formula of
synchronous detection method can also be extended to multi-
phase systems, such as four-system and six-phase system.
System implementation using actual harmonic loads is also
presented, as well as the test results. The merits of the
proposed method are its capability to operate under unbalanced
system by per-phase calculation, to avoid conversion error
by force waveform calculation, and to implement in very simple
manners. This dissertation has accomplished an active
filter design for current compensation and load balancing in
an unbalanced three-phase system.

Cover
Contents
1 Introduction
1.1 The Instantaneous Power Theory
1.2 Contents of the Dissertation
2 Synchronous Detection Method
2.1 Equal Power Synchronous Detection (PSD) Approach
2.2 Equal Current Synchronous Detection (CSD) Approach
2.3 Equal Resistance Synchronous Detection (RSD)Approach
2.4 Simulation Results of Synchronous Detection Method
2.5 Minimum Line Loss Approach
3 New Instantaneous Power Theory and Comparison with RSD Method
3.1 New Approach of the Instantaneous Power Theory
3.2 Unbalanced Sinusoidal System
3.3 Method Improvement
3.4 Simulation and Measurement Results
4 Synchronous Detection Method in Multi-Phase System
4.1 Multi-Phase PSD Method
4.2 Multi-Phase CSD Method
4.3 Multi-Phase RSD Method
4.4 Simulation and Measurement Results
4.4.1 Simulation Results
4.4.2 Measurement Result
5 Implementation and Test Results
5.1 Hardware Implementation
5.2 Measurement Results
5.3 Test Result of CSD Active Filter
6 Discussion and Conclusion
6.1 Discussion
6.2 Conclusion
References
Others