一种非隔离的高增益三端口直流变换器

A non-isolated high-gain three-port DC converter

针对含新能源发电系统中并联配置多组独立DC-DC变流器,存在故障率高、功率密度低、经济性差等问题,设计了一种集约型高增益三端口DC-DC电路。该三端口换流器分别连接供电单元、储能单元和负载,可实现任意两个端口的能量流动,采用二次升压回路来得到高增益的电压输出。首先对所提出的三端口换流器的3种工作状态进行原理分析,然后计算出换流器的电压增益,最后搭建一台额定功率为200 W的实验样机对理论分析进行实验验证,实验结果为,在输入电压为25 V情况下,换流器在3种工作模式下都能得到120 V的输出电压,其中储能电池的充电电流为3 A,放电电流为4 A,实验结果表明,在含储能单元接入的新能源发电系统中,该换流器能保证稳定高增益的电压输出。

Aiming at the problems of high failure rate, low power density, and poor economy in parallel configuration of multiple independent DC-DC converters in power generation systems containing new energy, an intensive high-gain three-port DC-DC circuit is designed. The converter is respectively connected to the power supply unit, the energy storage unit and the load, and can realize energy flow to any two ports. The secondary boost circuit is used to obtain a high-gain voltage output. First, analyze the principle of the three working states of the proposed three-port converter, then calculate the voltage gain of the converter and the stress of the switching device. Finally, an experimental prototype with a power of 200 W was built to simulate and verify the theoretical analysis, the experimental result is that when the input voltage is 25 V, the inverter can get an output voltage of 120 V in three working modes. The charging current of the energy storage battery is 3 A and the discharging current is 4 A. The experimental results show that In the new energy power generation system connected to the energy storage unit, the converter can ensure stable and high-gain voltage output.