Summary: | 碩士 === 國立臺北科技大學 === 電機工程系所 === 102 === This thesis presents a small signal analysis model of series resonant converter by intuitive method to design voltage controller. The small signal analysis of voltage controller is divided into software controller and hardware circuit. The software controller consists a PI controller and a voltage-to-frequency gain. The small signal model of hardware circuit is derived based on both that the output capacitor is small and the energy is transferred to load using constant current source. Thereby the gains of PI controller are yielded by Bode plot according to the specification of voltage loop. Moreover, simulated results by Simulink are carried out to analysis the controller design. In order to improve the power quality, a single-phase AC-DC converter with PFC is built and connected in the input of SRC. Finally, the influence of asymmetric PWM and burst mode control of SRC with fixed input voltage on output voltage and efficiency are analyzed.
In order to verify the correctness of proposed design method, a DSP-based SRC is constructed. The design result of controller and derived small signal models of SRC are all verified by frequency response analyzer, which shows that the tested results of SRC are closed to design results and the bandwidth of voltage loop is near to 2kHz.
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