- 學位論文
串聯油電複合電動機車之一體化發電啟動轉換器設計
A Novel Integrated Starter-and-generator Converter for Series Hybrid Scooter
摘要
本文主要研製用於串聯式油電複合電動機車之發電模組所需轉換器，該轉換器分別由一發電機驅動模組及一只雙向功率流動模組所建構。當引擎處於正常發電狀態下，發電機驅動模組將來自引擎發電機之三相交流電源整流為直流，隨後經由雙向功率流動模組降壓提供電動機車之馬達驅動器所需電能。為進一步提高複合電動機車之效能，轉換器之輸出並接一鋰電池做為能量緩衝，並對轉換器輸出端進行引擎發電之定功率調控，由於並接鋰電池具高功率密度可提供電動機車負載所需之瞬時功率，因此有效降低引擎發電機之備載容量。再者，因轉換器之輸出端為定功率控制可使其輸出電壓浮動於所並接之電池電壓上，故可省去電池輸出轉換電路。 當引擎需點火發電時，本轉換器對電池提供之電能進行昇壓並輸出六步波電壓以驅動發電機，此時發電機可作為電動機來啟動引擎達到自動點火運轉之目的。 所提系統皆由數位訊號處理器做為控制核心，配合功率級電路建構驗證平台，除以模擬負載驗證所建系統之有效性外，最後更於電動機車進行實車驗證。
並列摘要
The main purpose of this thesis is to design a converter for the power generation system of series hybrid scooter. The converter consists of a three-phase inverter and a bi-directional power flow converter. When the engine operates in generating mode, the three-phase AC power which is produced from the engine-generator will be rectified to DC power by the three-phase inverter, and then the bi-directional power flow converter steps down the DC bus voltage and provides the energy to the motor drive of the electric scooter. To enhance the performance of the hybrid scooter, the converter connects a Li-ion battery in parallel as an energy buffer and executes the constant power control for the engine-generator. The instantaneous power can be provide by the Li-ion battery due to its high power density. Therefore, the rated capacity of the engine-generator can be reduced effectively. Moreover, since the constant power control at the converter output terminal, it forces the output voltage to float on the battery voltage and a bi-directional converter for the Li-ion battery can be saved. When the engine operates in cranking mode, the proposed converter steps up the voltage level from battery and drives the generator using six-step current control method. At this time, the generator operates as a motor to start the engine. The proposed system consists of a DSP-based control stage and a power stage, and uses the electronic load to verify the function of the proposed converter. Furthermore, some results are measured in an electric scooter on dynamometer to show the effectiveness.