摘要
由于光伏、燃料电池一般输出电压较低,而母线电压较高,如果需要并网发电,前级的直流升压变换器要有很高的电压传输比,以实现高效地电能变换。基于基本直流变换器和开关电容变换器各自的优势,提出一种新的组合方式,推导出一系列的高升压比直流变换器拓扑,其基本思路为:在开关管关断期间,利用电感释放的能量,为多个开关电容进行并联充电,同时用脉宽调制(pulse width modulation,PWM)技术控制各电容的电压;开关管导通时,再将各电容串联起来,为负载供电,以提高变换器的升压比。分析各变换器的工作原理,并计算出各变换器的电压传输比。最后给出采用开关电容的高升压比变换器的详细设计过程以及实验波形,验证理论分析的正确性。
The output voltage of photovoltaic（PV） source and fuel cells is generally low. In the grid-connected power system, high step-up and high-efficiency DC-DC converters are needed due to the relatively high bus voltage of the grid-connected inverter. In this paper, a new method combined the conventional DC-DC converter and switched-capacitor（SC） converter was proposed on the basis of the respectively advantages. The basic principle is that during the switch is turned off, and energy released by the inductor can be used to charge the multiple capacitors in parallel whose voltages are controlled by pulse width modulation（PWM） technique. When the switch is turned on, the capacitors are in series to supply the load. Thus the voltage gain of DC-DC converter is increased. Based on this, a series of new topologies were derived. The operation principles and voltage gain of the proposed converters were analyzed. In the end, design process of the proposed converter, and experiment results were given to verify the correct of the theoretical analysis.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2015年第2期442-450,共9页
Proceedings of the CSEE
关键词
高电压传输比
高效率
开关电容
非隔离型
光伏电池
燃料电池
high voltage gain
high efficiency
switched capacitor
non-isolated
photovoltaic source
fuel cell
