Abstract
本論文旨在設計製作一單相三線式無輸出變壓器小型蓄電池儲能系統。此儲能系統之電力電路架構只使用一組換流器。為免用輸出變壓器而能直接提供單相三線輸出，此換流器具有三個臂，利用中間臂的切換補償負載之不平衡，使在台電中斷時之兩組電壓能維持平衡；而在台電正常時，中性線的電流為零。至於左､右兩臂之切換則主要係用以達成本論文所提儲能系統之操控功能，藉由所提之解耦控制技巧，使中間臂及左右臂之切換控制可獨立操作。本儲能系統採多迴路控制器架構，外迴路為各模式控制器，用以產生達成各操作模式目的之換流器切換控制電流命令；內迴路為電流強迫切換機構，利用電流強迫次諧波脈寬調變切換技巧，可使換流器之電流緊密追隨其命令。所提蓄電池儲能系統之各模式操作原理及控制器之設計於本論文中均有詳細敘述。在以 EMTP 模擬證實所提系統之可行性後，即著手製作電路完成一 2KVA 系統，並再由一些實測結果，顯示所提儲能系統之性能。In the thesis, a single-phase three-wire transformerless,small battery energy storage system (BESS) is designedand implemented. The power circuit of the proposed BESS issimple, since it consists of only one converter. It hasthree legs to provide single-phase three-wire 220/110Voutput without using transformer. For switching control, theBESS is decoupled into differential mode and common modesubsystems. Every subsystem has its own inner-loop current-forced switching control mechanism and outer-loop controllerfor producing current commands of various operating modes.The controllers of the differential mode are mainly designedto control the magnitude and waveform of main voltage (220V)source and to achieve the functions of BESS. As to the commonmode subsystem, its controllers are used to maintain thebalance between two subcircuits (110V circuits). In addition,the common mode controllers can also keep the current inneutral line of utility grid be zero. The operationprinciple of the proposed BESS and the design of controllersin various operating modes are described in detail.Feasibility of the proposed BESS is first confirmed by someEMTP simulation results. Then the implementation of a 2KVABESS is made. The performance of the proposed BESS is furtherdemonstrated by some experimental results.