Research On Shunt Active Power Filter Of Coal Supply System

With the various power electronics being widely used, the power pollution problems such as harmonics and reactive current are growing in coal power grid. APF(Active Power Filter) is recognized as one of the most effective means to realize coal power grid harmonic control, But APF in domestic application is still hanging behind compared with the developed countries.so doing research on active power filter has important practical value.On the basis of the traditional instantaneous reactive power theory and mine complex load conditions, a harmonic detection algorithm based on the ip-iq is proposed from the perspective of vector analysis.Which simplifies the calculation by eliminating the PLL and trigonometric calculations.the other one is current track circuit, it generates logic signal to control electronic devices according to the relationship between the current command signal and actual compensation current. In the current track aspect, an improved hysteresis control method is proposed by adding a voltage to the output command voltage, which is proportional to the instantaneous value of the voltage. The new control method can reduce the interference of the output voltage caused injection terminal voltage, and reduce the error of the output currentSimulation and experimental results verify the accuracy and usefulness of this control method,which meets the need of power grid harmonic elimination.