基于dq坐标变换的畸变电流矢量检测法

非线性负荷电流谐波抑制及无功补偿的一个重要手段是采用有源电力滤波器，其中关键环节在于实时准确地检测出谐波和无功电流。提出了基于dq坐标变换畸变电流的矢量检测法，其基本原理是对基于dqo坐标系下广义瞬时无功理论和检测方法进行简化，运用单矢量和双矢量投影的方法，检测出负荷电流的基波正序分量。该方法在系统电压对称或畸变的情况下，均可准确快速地检测出负荷电流畸变量，从而使装置对荷电流谐波及无功进行有效补偿，还运用软件PSCAD／EMTDC进行仿真，结果表明该检测方法是准确可行的。

Distorted current detection based on dq coordinate transformation

Active power filter is mainly used in restraining harmonics and compensating reactive power.The real-time and exact detection of harmonics and reactive currents is its essential technique.A vector method based on dq coordinate transformation for detecting distorted current is developed.It is the simplified method,which is based on the generalized theory of instantaneous reactive power in dqo coordinates.It detects the fundamental positive-sequence portion of load current using single-vector and double-vector projections.In the conditions of both balanced and distorted system volt-ages,the distorted load current can be precisely detected for the effective harmonics and reactive-power compensation of load currents.The simulation is carried out with PSCAD/EMTDC software,which verifies that the proposed method is feasible and correct.