摘要
单电压环控制的三电平Buck变换器暂态响应慢,并且滤波器参数的变化、输入电压波动和负载变化等扰动影响了电压的控制精度.针对上述不足,本文研究了一种基于扰动观测器的电压控制策略.从理论上研究了扰动观测器抑制外部扰动的有效性及飞跨电容的电压控制方法和算法,整定了电压控制算法的参数.仿真结果表明:所研究的控制方法能有效抑制输入电压波动和被控对象的参数变化等扰动,并且能大幅提高电压环的暂态响应速度.
The transient response speed is low through a single voltage control method. There are some varieties of disturbances such as plant's parameters variation,input voltage fluctuation,uncertain loads in a tri-level buck converter control system. These disturbances have a signification effect on the output voltage control precision of a tri-level buck converter. Aiming at the above disadvantages,the voltage control strategy based on disturbance observer( DOB) has been proposed and investigated in this paper. The effectiveness of the DOB suppressing disturbances has been investigated. Secondly,the voltage control method and the voltage control algorithm of the flying capacitor have been researched. The control parameters of the output voltage control algorithm have been tuned.Finally,the effectiveness of the proposed control strategy and algorithm has been verified through simulation results. The voltage transient response speed of the tri-level buck converter has been greatly increased.
引文
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