本论文提出三相并联型有源滤波器的两种新的控制方法，即正弦波化控制和瞬时无功功率的控制方法。
In this paper, we propose and discuss two new control methods for three phase shunt APFs: the sinusoidal line current control method and the instantaneous reactive power compensation control method.
论述了利用瞬时无功功率理论从三相不对称电流中正确检测出三相正序有功电流，并用计算出的指令电流对系统进行补偿的原理。
Based on the instantaneous reactive power theory the method correctly detects the active positive-ord current from unsymmetrical currents and applies calculated command current to compensate system.
如何定义三相系统的瞬时无功电流、瞬时无功功率一直是学术界关心的问题。
How to define instantaneous reactive current and reactive power in three-phase non-sinusoidal asymmetrical systems is still a concerned problem by academia.
从物理和数学的角度，对单相电路、三相电路瞬时有功功率和瞬时无功功率的概念进行了剖析。
From physical and mathematical points of view, this paper analyses the nature of instantaneous active and reactive power.
然后是三相四线制无功补偿发生器的理论基础（主要是瞬时无功功率理论和IGBT脉冲产生的空间矢量法）；
Thirdly, this paper introduces academic base used in this equipment , mainly are instantaneous Var power theory and Special Vector Method for generating pulse used springing IGBT;
然后是三相四线制无功补偿发生器的理论基础（主要是瞬时无功功率理论和IGBT脉冲产生的空间矢量法）；
Thirdly, this paper introduces academic base used in this equipment , mainly are instantaneous Var power theory and Special Vector Method for generating pulse used springing IGBT;
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