| Summary: | 碩士 === 國立臺灣科技大學 === 電子工程系 === 101 === The fuel cell stacks present low output voltage with wide range of variation. In order to provide the load a stable energy source, a step-up DC-DC converter must be inserted between the fuel cell stacks and the load. In this thesis, the current-fed full-bridge boost converter with secondary voltage-doubler rectifiers is adopted. A digital controller is in charge of coordinating the gate driving signals among various power converter modules. Combined with the enhanced control area network (ECAN), the output current command can be adjusted. Therefore, the output power can be suitably distributed according to the CAN bus module. An auxiliary power supply is designed to provide four output voltages. Vcc1 (15 V/1 A) and Vcc2 (?{15 V/1 A) are supplied to the driver IC, PWM control IC, and voltage/current sensors. Vcc3 (12 V/2 A) and Vcc4 (12 V/1 A) are supplied to the DSP digital controller, fan, CAN bus transmitter/receiver, and protection circuitry. To ensure the system stability and lifetime of the fuel cell, over-current protection (OCP) and over-voltage protection (OVP) are fulfilled. Finally, two 2.5-kW DC-DC boost converters for fuel cell applications are designed, implemented and tested. Experimental results are shown to verify the feasibility of the developed system. A high conversion efficiency over 90% can be achieved.
|
|---|
