The Study of Harmonic Suppression and Reactive Power Compensation

Abstract

With the development of modern industry, more and more semiconductor-based devices have been used widely. Such equipment presents nonlinear impedance to the utility, generating large harmonic currents with well known adverse effects, such as low power factor, low efficiency and destruction of other equipment. Also, some precision instruments and communication equipment will be interfered. Therefore, utility power quality has become an important issue recently. This paper presents a hybrid active filter including two functions: current harmonic detection and reactive power compensation. The current harmonic detection is based on. The reactive power compensation utilizes the measured voltage and the estimated fundamental current to calculate reactive power. After the above information has been calculated, the corrective current reference signals can be generated for the active filter. In this way, the two control functions are integrated together so that one active filter can accomplish two functions simultaneously. The system is modeled in MATLAB SIMULINK to consist of the non-linear loads, with a hybrid active filter to compensate for the harmonic current and reactive power. The simulation results show that the proposed hybrid active power filter has the expected performance.