基于谐振电压腔中点采样的预测电流移相控制策略

Predictive Current Phase Shift Control Strategy Based on Midpoint Sampling in Resonant Voltage Cavity

为了提高移相DC/DC变换器的动态响应和稳定性以及消除变换器直流偏磁,提出了一种基于谐振电压腔中点采样的预测电流移相控制。首先,分析变换器的开关模态,得到每个模态下的电感电流斜率。然后,在三角载波的零值和中值处对电感电流进行采样,通过理论分析,得到移相角的预测表达式。进一步分析电感参数对预测电流移相控制的影响,引入了递推最小二乘法,用以消除电感参数的影响。最后,针对所提控制策略进行了仿真实验,结果验证了所提控制方法的有效性,提高了移向DC/DC变换器的动态响应和稳定性,并解决了变换器的直流偏磁问题。

In order to improve the dynamic response and stability of the phase-shifting DC/DC converter and eliminate the DC bias,a predictive current phase-shifting control based on mid-point sampling in resonant voltage cavity is proposed.Firstly,the switching modes of the converter are analyzed and the inductance current slope under each mode is obtained.Then the inductance current is sampled at the zero value and median value of triangular carrier,and the prediction expression of phase shift angle is obtained through theoretical analysis.The influence of inductance parameters on the predictive current phase shift control is further analyzed and the recursive least square method is introduced to eliminate the influence of inductance parameters.Finally,simulation experimental verification of the proposed control strategy is carried out to verify the effectiveness of the proposed control method,which improves the dynamic response and stability of the moving DC/DC converter and solves the DC magnetic bias problem of the converter.