基于MPC的耦合电感飞跨电容双向DC/DC变换器功率均衡解耦控制策略

DECOUPLED POWER-BALANCING CONTROL STRATEGY FOR COUPLED INDUCTOR FLYING CAPACITOR BI-DIRECTIONAL DC/DC CONVERTER BASED ON MPC

耦合电感功率变换器因耦合电感阻抗、电感值等参数差异易导致功率不均衡。针对耦合电感飞跨电容双向DC/DC变换器,提出一种基于模型预测控制(MPC)的功率均衡解耦控制策略。通过对变换器原理进行分析,建立基于电感电流解耦的数学模型,得到包括电感电流和飞跨电容电压等6个控制变量的解耦控制方法。在此基础上,提出基于MPC的功率均衡解耦控制策略。同时,为降低MPC算法的运算负荷,根据解耦控制模型重构模型预测价值函数,实现各控制变量独立动态寻优,使系统能在稳定控制输出电压及飞跨电容电压的同时,实现两相耦合电感的功率均衡控制。最后,通过理论分析及实验对所提策略进行有效验证。

Coupled inductor power converters are prone to power-imbalance due to the difference in coupled inductor impedance and inductance.A decoupled power-balancing control strategy based on model predictive control(MPC)for coupled inductor interleaved flying capacitor bi-directional DC/DC converters is proposed in this paper.By analyzing the working principle and constructing the mathematical model based on inductor current decoupling of the converter,the decoupled control method of the six control variables including the inductor currents and the flying capacitor voltages are obtained.On this basis,a decoupled power-balancing control strategy based on MPC is proposed.Meanwhile,in order to reduce the computational burden of the MPC algorithm,the model predictive cost function is reconstructed according to the decoupled control model,and the independent dynamic optimization of each control variable is realized,so that the system can stably control the output voltage and the flying capacitor voltage while realizing powerbalancing control with two-phase coupled inductor.Finally,the proposed strategy is effectively verified through theoretical analysis and experiments.