单参数控制的数字DC-DC变换器设计及其FPGA实现

传统的数字DC-DC变换器采用多参数控制方法,因而增加了控制器设计的复杂度和硬件开销;一种单参数控制的数字变换器控制方法被提出,其数字补偿器由一个乘法查找表和一个加法器构成,使得执行数字控制律的逻辑电路得到显著简化;在分析了控制参数对变换器性能的影响后,提出了获得系统最佳瞬态性能的设计条件;基于所提的单参数控制方法,完成了数字Buck变换器的FPGA实现,测试结果表明:在1MHz的开关频率下,对于1.8V的输出电压,电压纹波律小于1%,电压调整率为6mV/V,负载调节律为8mV/A;负载电流为0.3A时,转换效率高达91.9%。

FPGA Implementation of Digital DC-DC Converters with Single-parameter Control

For digital DC-DC converters,the traditional control methods with multi-parameters control complicate the design process and increase the hardware cost of digital controller.A new digital control method with only one control parameter is proposed,and the digital compensator accordingly consists of one look-up table and one two-input adder,so design process is simplified and the logic circuits for executing digital control law is notably reduced.After analyzing the effects of control parameter to DC-DC converters,the design condition for optimal dynamic performance is given.The digital controller of buck DC-DC converters is implemented on FPGA,and the experimental results indicate that the output ripple rate is less than 1%,line regulation is 6mV/V,load regulation is 8mV/A for 1.8V output voltage at 1MHz switching frequency,and the power efficiency is up to 91.9% for 0.3A load current.