# Using “STF-PQ” Algorithm and Hysteresis Current Control in Hybrid Active Power Filter to Eliminate Source Current Harmonic

ABSTRACT:

According to importance of power quality in power network, improvement of compensator equipment and ways of efficiency increasing can reduces destroyer effect on network. Active power filters as more importance and finance in network and industrial has depended detector algorithm and switching technique. This paper presents a novel algorithm (STF-PQ). This algorithm base on harmonic extract is divided into two parts as feedback loop and feed forward loop. Then, the hysteresis current control has been used to produce the switching pattern. A comparison between PWM and hysteresis current control has been performed that shows the efficiency and simplicity of hysteresis current control. Simulation of this filter has been done in Matlab/Simulink to prove the good performance of STF-PQ and hysteresis current control in hybrid filters.

KEYWORDS:

1. Hybrid active power filters
2. Self tuning filter
3. Hystrsis current control

BLOCK DIAGRAM:

Fig.1 Parallel hybrid active filter configuration

EXPECTED SIMULATION RESULTS:

Fig.2 simulation Results

CONCLUSION:

According to development of power systems in industrial such as UPS, speed control of electrical machine, electrical furnace, computers and non-linear load that cause increasing of harmonic in network, Undesirable effect of harmonic is one of power transfer problem. This is why of standard codifying on THD limitation. Thus, it is necessary to detect and remove it until under permit limit. In this paper a novel algorithm of “STF-PQ” has been proposed to detect harmonics in power system. Then hysteresis current control has been used to make the reference current due to its simplicity and high accuracy. The comparison between PWM and hysteresis proves that use of PWM has more complexity and calculation to generate pulses. Simulation results show the efficiency of this power filter in harmonic elimination.

REFERENCES:

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