| Summary: | 碩士 === 國立臺灣科技大學 === 電機工程系 === 104 === This thesis aims to design a power converter for nine-phase generator, whose magnetization consists of dc as well as permanent-magnet excitations. The output of the nine-phase generator is first connected in series with capacitors to counteract the equivalent armature inductance for increasing output power capacity. A single switch boost type ac-dc power converter introduced behind the capacitor will feedback its output dc current for the closed-loop control of current to yield the required power from the generator. Finally for the three phase power inverter, a digital phase-lock loop is designed to calculate the phase-angle of the grid voltage to facilitate frame transformation for the voltage and current closed-loop control of the inverter. In addition, a proportional-integral control is given for dc-link voltage to maintain its stability under load variation.
The models of nine-phase hybrid excitation generator, single switch boost type ac-dc power converter as well as three-phase power inverter are built and analyzed by using Matlab/Simulink. A 32-bit digital controller, “TMS320F 28335”, is used as the control core, and all the control strategies are accomplished by software programs in order to reduce circuit components. The physical circuits of converter and inverter are built and measured. The generator output is 1162.8 W with 1100.9 W transmitted to the power grid. The phase current total harmonic distortion of three-phase inverter is 8.07%. The overall efficiency of the boost converter and power inverter is 94.7%. The experimental results verify the feasibility of the proposed power conversion and its control strategy.
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