PI control of multi level inverter based shunt active power filter for harmonic mitigation in three phase systems

Abstract

Cascaded multilevel inverter is a power electronic device developed to synthesize a desired voltage or current waveforms from several levels of dc voltages making use of its reduced switching stress and modular structure. Such inverters have been recognized as very attractive topologies for implementing shunt active power filters in medium and high voltage applications. This paper presents a five-level cascaded multilevel inverter based Shunt Active Power Filter (SAPF) to compensate reactive power and mitigate the harmonic currents generated by the non-linear loads. The functioning of the proposed system is improved by the inclusion of PI controller for dc-side voltage regulation of SAPF and triangular carrier current controller for the generation of switching pulses for the inverter switches. The control strategy of SAPF also incorporates Synchronous Reference Frame (SRF) theory to extract the harmonic components from distorted line currents which in turn are utilized in the production of required reference compensation currents. This paper primarily focuses on the mitigation of the harmonics produced by the use of nonlinear loads with the aid of PI controller for dc voltage regulation. Extensive simulations are carried out to validate performance of the proposed SAPF system using MATLAB/ SIMULINK for diode bridge rectifier with RL load. The dynamic responses of the proposed SAPF system is verified under varying load conditions.

Indirect Effective Controlled Split Source Inverter-Based Parallel Active Power Filter for Enhancing Power Quality

“…A detailed survey on SAPF has been archived in the literature [24]. Conventional proportional integral (PI) controllers for the voltage and current control were used in [25,26] to regulate the harmonic current and the DC voltage. However, to achieve versatility in the PI controller, an accurate model of the system should be known, which is difficult to obtain with the given nonlinearity, load disturbances and parameter variations.…”

Harmonic Components Estimation in Power System Using Bacterial Foraging Optimization Algorithm and Stochastic Gradient Algorithm With Variable Forgetting Factor

“…Thus, use of an effective method is essential for measuring frequency in the presence of noise and high order harmonics. The effects of harmonics in power systems can be decreased by using harmonic filters and harmonic suppressors [1][2][3]. Before designing such filters, the amplitudes and phases of harmonics generated in power systems must be known.…”