电流滞环控制策略具有稳态过程精度高、响应速度快的优点，但是改进前的控制策略在负载电流突变过程中控制效果不够理想。为了缩短变换器的动态响应时间和提高负载调整率，本文在原有电流滞环控制策略的基础上进行了改进，提出一种稳态控制和暂态控制相结合的控制策略，并对提出的改进策略进行了详细地理论分析和数学建模。Buck-Boost DC-DC变换器稳态控制采用改进前的电流滞环控制策略。负载电流突变暂态过程，既要考虑电感安秒平衡原理，又要满足电容充放电平衡，结合变换器负载电流突变暂态工作原理和每个阶段电路满足的微分方程，推算出开关管S开通或关断的合理时间点，从而精确的控制开关管S动作，以改善Buck-Boost DC-DC变换器的动态性能。详细地分析了Buck-Boost DC-DC变换器的起动过程。 在 Matlab/Simulink仿真环境下，对改进前和改进后电流滞环控制的变换器进行了仿真验证和对比分析。完成了控制策略的软件设计和程序编写，基于STM32F407VGT6处理器制作了一台Buck-Boost DC-DC变换器，采用改进前电流滞环控制策略和改进后电流滞环控制策略进行了硬件测试。当变换器输入电压变化、负载电流突变时，对输出电压的影响进行了实验验证，获取了实验波形和对比分析结果。 仿真和实验测试结果均表明，改进后的电流滞环控制策略有效地解决了改进前电流滞环控制方法存在的问题，更好地改善了变换器暂态过程的性能参数，缩短了动态响应时间，提高了负载调整率。进一步验证了所提出的控制策略是可行的，所进行的理论分析是正确的。

Although the existing current following control strategy possesses high stable precision and fast response speed, its transient performance is not very ideal while the load changes. In order to reduce the dynamic response time and improve the load regulation, a modification based on exsiting current following control strategy is proposed. A control scheme which is the combination of stable state and transient is developed. When the Buck-Boost converter is working in steady state, the existing current following control strategy is used. However, when the converter is working in transient state，both the inductor current and capacitor charge balance should be taken into account. According to the work principle and the differential equations of each stage in the transient state to work out the reasonable time points when switch turns on or off, so it could be controlled more accurately. Therefore, dynamic performance of converter will be improved. In the same time, the boot process of Buck-Boost dc-dc converter is analyzed in detail. The existing and modified model were simulated by the Matlab/Simulink software seperately, the waveforms were received and analysized. An example is given to show the parameter design steps based on STM32F407VGT6. The existing and modified current following control strategies were adopted respectively. Experiments are made on the example. The influence on the output voltage when the input voltage and the load suddenly changes are tested, also the waveforms were received and analysized. Both the simulating result and the experiment result show that the improved current following control strategy effectively solves the problems existing in the current control method before improvement. It improves the performance of transient state. Mainly shortening the dynamic response time and improving the load regulation. It indicates that the proposed approach is feasible and the analysis is correct. Also the converter meets design index.