In this paper, a new control method is proposed for microgrid-connected voltage source converters (VSCs), which generally contain voltage and current control loops. The voltage of the point of common coupling (PCC) is analyzed by recursive least squares (RLS) algorithm and its fundamental positive symmetric components are extracted by the voltage control loop. Using the fundamental positive symmetric component, the required active and reactive powers are injected into the main grid via the microgrid-connected VSC without any distortions. This control loop is equipped with two PI controllers for the DC and AC voltage regulation. On the other hand, the same as the PCC voltage assessment, the local load current signal is evaluated by the RLS algorithm in the current control loop, with its harmonics and unbalanced components extracted. Eventually, the reference signal is obtained using these two control loops for generating switching pulses of the microgrid-connected VSC. Accordingly, the VSC acts as a shunt active power filter (APF), and also simultaneously injects the required active and reactive powers to the main grid. The proposed control method has high accuracy and fast dynamic response, and also its performance is independent of system parameters. The effectiveness of the proposed method has been verified by simulation and experiment.

在本文中，针对通常包含电压和电流控制回路的微电网连接电压源换流器 (VSC) 提出了一种新的控制方法。公共耦合点（PCC）电压通过递归最小二乘法（RLS）算法进行分析，电压控制回路提取其基本正对称分量。使用基本的正对称分量，所需的有功和无功功率通过连接到微电网的 VSC 注入主电网，没有任何失真。该控制回路配备了两个用于直流和交流电压调节的 PI 控制器。另一方面，与 PCC 电压评估相同，本地负载电流信号通过电流控制回路中的 RLS 算法进行评估，并提取其谐波和不平衡分量。最终，参考信号是使用这两个控制回路获得的，用于生成连接微电网的 VSC 的开关脉冲。因此，VSC 充当并联有源电力滤波器 (APF)，并同时向主电网注入所需的有功和无功功率。所提出的控制方法精度高、动态响应快，且其性能与系统参数无关。通过仿真和实验验证了所提方法的有效性。并且其性能与系统参数无关。通过仿真和实验验证了所提方法的有效性。并且其性能与系统参数无关。通过仿真和实验验证了所提方法的有效性。