基于正交特性的广义无功电流分解与检测

Decomposing and Detecting of Generalized Reactive Current by Orthogonal Characteristics

为克服基于瞬时无功功率理论的无功谐波电流检测法的不足,利用广义有功与无功分量间的正交特性,推导出电导性比例系数K的计算公式及其简化算法;提出了一种适用于任意波形周期性电压电路的广义无功电流检测方法。该方法无需坐标变换、锁相环及滤波器,计算量少,适用范围广,有较好的实时性。对正弦电压感性负载、非线性负载以及电压畸变3种电路的仿真验证及与基于瞬时无功功率理论的ipiq检测法进行比较的结果证明了该方法的正确性与适用性。

Nonlinear circuit with probabilistic periodical voltage and current was detined as two vectors of H-dimensions Inner Product Space, then based on the S. Fryze＇s time-domain power theory, the current was decomposed into two components that were generalized active current and generalized reactive current, and the generalized active current component was similar to voltage in shape and phase only in peak value. Using the orthogonal characteristics between the two current components, the conductance proportion coefficient K between voltage and generalized active current was proposed. Furthermore, a novel detecting method of generalized reactive current and its simplified formula, which needs not coordinate transform, phase-locked loop and filter, was presented. This method can be extensively used in circuit with probabilistic periodical voltage and probabilistic load. At last, the detecting method was simulated under three situations including sinusoidal voltage-inductive load, sinusoidal voltage-nonlinear load and nonsinusoidal voltage-nonlinear load, moreover, it was compared with ip iq detecting method based on the instantaneous reactive power theory. Simulation results and numerical calculation verify the correctness and advantages of the proposed method. Decomposing and detecting method proposed in this paper was significant in power analysis and reactive power compensation due to its simple calculation and extensive use fields.