基于无差拍算法与扰动观测器的逆变器控制

Joint Control of Inverter Based on Beat Free Algorithm and Disturbance Observer

为增强不间断电源运行时对扰动电流的抵抗能力,针对电压型逆变器提出了一种基于扰动观测器的动态补偿策略。首先,在dq坐标系下建立LC滤波器状态空间方程,对传统双闭环控制结构进行改进,利用无差拍算法代替传统电流内环,加强电流控制的响应速度与精度;其次,建立基于LC滤波器的状态观测器,设计控制器提取扰动电流。该方法的优点在于引入最优控制理念,进一步提升逆变器的暂态特性,同时利用扰动观测器提取电流扰动并反向补偿,增强逆变器的抗扰能力。最后,基于实际逆变器平台设计不同类型负载投切实验,实验结果验证了所提方法的有效性与正确性。

In order to enhance the resistance of uninterruptible power supply to disturbance current during operation,a dynamic compensation strategy based on disturbance observer is proposed for voltage-sourced inverter.Firstly,the state space equation of LC filter is established under dq coordinate system,and the traditional double closed loop control structure is improved.The traditional current inner loop is replaced by the beat free algorithm to enhance the response speed and accuracy of current control.Secondly,the state observer based on LC filter is established,and the controller is designed to extract the disturbed current.The advantages of this method are that the optimal control concept is introduced to further improve the transient characteristics of the inverter,and the disturbance observer is used to extract the current disturbance and reverse compensation to enhance the disturbance immunity of the inverter.Finally,experiments of different types of load switching are designed on the actual inverter platform,and the experimental results verify the effectiveness and correctness of the proposed method.