A Novel Harmonic And Reactive Power Current Detecting Approach Used In Active Power Filter

As technique of power electronics develops, the load with nonlinear, impactive, unbalanced characteristics such as current rectifiers, frequency converters, arc furnaces have been increasingly used in power network in recent years. They generate lots of harmonics and cause distortion in power electrical network current (voltage). Power networks had been polluted by harmonics, which do harm to electrical equipments. Harmonic pollution has been one of the non-negligible problems in power supply systems and catches people's eye.To problem that caused by harmonic, this paper depicts the reason of harmonic's bringing and the harm of harmonic introduces active power filters that are in common use and its principle and analyzes harmonic and reactive power current detecting approaches used in active power filter. On this condition, a harmonics and reactive power current detecting approach that the amplitude of fundamental component is separated in it is advanced. This approach is called FAS. This approach uses characteristics of trigonometric function, respectively computes the amplitude of fundamental component and inactive power current separates them by low pass filter and acquires and inactive power current. This approach the problem of conquers phase excursion and frequency drift that anciently adopts fixed frequency filter and its frame is simple. In order to prove the correctness of the approach, some necessary reasoning and a simulate research based on the approach are done in this paper. The effect to compensating harmonic caused by each parameter's change is expounded. The result of the simulation indicates the feasibility of the approach. The practical circuit is designed and analyzed.