Design of Active Power Filter with Active and Reactive Power Injection Capability, Using Multilevel Inverter and Photovoltaic Arrays
حنتولي, نائل نجيب
An-Najah National University
The Hybrid Active Power filter (HAPF) consists of shunt active power filter connected with series active power filter at a common linking point. Itworked perfectly with total benefits of shunt APF and series APF. In other words, it can mitigate both the current and voltage harmonics. Subsequently, the HAPF can mitigate nearly all kinds of power purity troubles seen by distribution network. The shunt active power filter is controlled based on the “generalized theory of the instantaneous reactive power in three-phase circuits (p-q theory)", to compensate the load harmonics. The series active power filter is controlled based on the dual instantaneous reactive power theory to compensate the load harmonics. (HAPF) used 27-level asymmetrical inverters. Each phase of these inverters is composed of three ‘H’ bridges, supplied by three independent photovoltaic arrays Scaled in the power of three, delivering 12.5 kVA to each phase, 10kVA for shunt active filter and 2.5 kVA for series active filter, using multilevelinverters with more than 20 levels can deliver current waveforms with negligibletotal harmonic distortion. So they can implemented in active filter application without the need of filters. The outputs of inverters connected directly through a transmission line. In addition to the capability of harmonic elimination of both current and voltage drawn from the source, the combined system can produce real and reactive power to feed the loads during prolonged voltage outagesor source shortage. A battery pack used as dc link, which is charged from photovoltaic array connected to the battery through a maximum power point tracker and charge controller.The injection of real and reactive power depends on the state of charge (SOC) of batteries, the system frequency, type of the load, and power factor at the common linking point. The proposed Unified (HAPF) strategy is simulated in MATLAB SIMULINK and the results are shown.From simulation results, the system can mitigate all voltage and current harmonics and reduce the total harmonic distortion from 22% to 1%. In the other hand, it support the electrical network by injecting real power when it’s needed and maintain the stability of the electrical network. By using voltage reference generation control we will overcome the voltage matching problems, reduce the total harmonic distortion (THD) to minimum and eliminate the need of transformers.