中文摘要：

分析四象限级联型变频器功率单元数学模型的基础上，以输入和输出瞬时有功功率平衡为控制目标，给出了PWM整流电流指令。为保证各频率电流的准确跟踪，提出了复矢量PI（complexvectorPI，CVPI）调节器，实现了各频率电流的完全解耦控制，论证了CVPI调节器相比传统调节器，对谐振频率变化具有更好的鲁棒性。同时，建立了基于卡尔曼（Katman）滤波的直流母线输出电流辨识模型，实时地辨识电流大小及其频率。构建了功率单元实验平台，对所提控制策略的正确性与可行性进行了实验验证。

英文摘要：

Based on the mathematical model of power cells in four-quadrant cascade converters, a current control strategy for PWM rectifier was proposed with the control target being the balance of the input and output instantaneous power. The complex vector PI （CVPI） regulators were introduced to track various frequency currents and decoupled control completely. CVPI regulators were proved to have better robustness than traditional regulators with the resonant frequency change. Moreover, the DC bus output current model based on Kalman filter was established to identify the current magnitude and frequency in real time. The proposed control .strategy was validated by the experimental results based on the platform of power cells.