单周控制的三相四桥臂有源电力滤波器

ue to the use of diverse electric loads, the power quality problem in the power distribution systems can be very complex, especially in four-wire distribution systems. A three-phase four-leg active power filter (APF), controlled by one-cycle controller is presented. The one-cycle control that belongs to nonlinear control methods makes the average value of switching vectors be equal to the reference value in one switching cycle. So the steady and the transient errors are eliminated. This scheme doesn't need any measured quantities of three-phase load currents and three-phase input voltages. And also the complicated calculations of the harmonics and reactive current components and the use of multipliers are eliminated. The controller used has simple structure, which is composed of two parts: one-cycle controller with the three-phase bridge that compensates harmonic and reactive currents, and one-cycle controller with the four-leg half-bridge that compensates zero sequence current. The mathematical simulation results verify that the APF with one-cycle control can compensate the harmonics, reactive currents and zero sequence current effectively, accurately and immediately.