摘要
文章给出了应用于高频数字控制DC-DC系统设计的两种方法。基于功率级的S域平均模型,采用传统的Redesign方法,得到数字PID控制的系统离散模型。针对数字PID控制的DC-DC系统的负载调节能力,提出了一种采用Direct-Digital方法实现的三阶数字控制器。基于Matlab/Simulink的系统仿真结果表明,当负载电流在500mA到1A跳变时,提出的三阶补偿系统的最大过冲电压160mV,稳定时间为30μs,相比二阶PID补偿系统的过冲为450mV,稳定时间为110μs,负载调节性能得到很大的改善;同时,当输入电压在1μs内从3V跳变到5V时,三阶补偿系统的过冲电压和稳定时间分别为450mV和45μs,相比二阶补偿系统的过冲为610mV,稳定时间115μs,线性调节能力也得到较大改善。
Two methods adopting in system design of digitally controlled DC-DC Converter are presented. Based on the average model of power stage in S-zone, we can get the discrete model of this DC-DC system with 2^nd PID compensator, using classical Redesign-method. A new 3^rd compensator taking advantage of Direct- Digital method to improve load transient response is proposed. The Matlab/Simulink stimulation results are shown that the maximum overshooting voltage of 3^rd compensation system is around 160 mV and the steady time is about 30 μ s when load current changes from 500mA to 1A in 1μ s, while 450mV and 110 μ s for 2^nd PID compensation system. At the same time, the maximum overshooting voltage of 3^rd compensation system is around 450mV and the steady time is about 45 μ s when input voltage changes from 3 to 5 in 1μ s, while 610mV and 115 μ s for 2^nd PID compensation system.The load regulation and linear load capability of 3^rd compensation system is improved greatly compared to system using 2^nd PID compensators.
出处
《电子与封装》
2009年第11期29-33,共5页
Electronics & Packaging
