A Transformer Integrated Filtering System for Power Quality Improvement of Industrial DC Supply System

Summary This manuscript presents a novel mathematical morphology‐based shunt active filter (SHAF) for improving the power quality (PQ) in microgrid applications. The proposed approach is more concerned about the integration of renewable energy such as photovoltaic (PV) system and nonlinear load in the grid. On PQ, accuracy, and real‐time application point of view, in the proposed approach, a two‐way control strategy is developed. Firstly, to regulate the duty ratio of a boost converter (BC) and PV performance, a sliding mode control (SMC)–based novel maximum power algorithm (MPA) is proposed. Secondly, to eliminate the nonlinearity selectively, an improved active and reactive current decomposition (IP − IQ) technique is proposed. The improved IP − IQ contains a low pass mathematical morphology filter (LMMF), to extract the fundamental dc component. The proposed approach eliminates the conventional αβ and dq transformation, with the reduced cost of computation and improved tracking speed. To validate the proposed two‐way control strategy, it is simulated through MATLAB software, and the proposed results are compared with the conventional MPA and low pass filter–based dq (CLPF‐dq) approach.

Section: System Modeling and Controller Designmentioning

confidence: 99%

“…The main reason for using the opening (∘) and closing (∙) is to flatten the spiky boundaries and fill the narrow gaps in a signal, respectively . Two different filters such as opening and closing filters are implemented through cascade connection in a different order.…”

Section: System Modeling and Controller Designmentioning

confidence: 99%

Application of mathematical morphology for power quality improvement in microgrid

Sahoo

Routray

Rout

2020

“…(6) as in Eqn. (7) by introducing a damping term. The proportional gain decides the dynamics of the system, phase-margin and gain-margin.…”

Section: Proportional Resonant Controller For Sapfmentioning

confidence: 99%

“…With Eqn. (7), the PR controller is more easily realizable in digital systems due to finite precision.…”

Section: Proportional Resonant Controller For Sapfmentioning

confidence: 99%

See 1 more Smart Citation

Optimization of DC‐link voltage regulator using Bat algorithm for proportional resonant controller‐based current control of shunt active power filter in distribution network

Balamurugan

Nataraj

Baladhandautham

2020

In this article, proportional resonant (PR) controller‐based pulse width modulation (PWM) current control for three‐phase, three‐leg SAPF with the optimized dc‐link controller is implemented to compensate for current harmonics produced by nonlinear loads. The optimization of the dc‐link voltage regulator is implemented using Bat Algorithm (BA). The stability of the current controller with the proposed system with a mathematical model is evaluated in the time and frequency domain. Instantaneous real and reactive power theory (pq‐theory) is applied for reference currents generation. Simulation of the proposed controller is performed in MATLAB/Simulink environment. The controller is implemented in FPGA platform and the results of simulation are verified with the experimental prototype. The optimized dc‐link results in the improved performance of SAPF. The new dimension of the PR controller in a grid‐connected system for harmonic regulation is implemented and validated with experimental results. The objective of reduced current harmonics with a minimum per phase fundamental current and unity power factor at the point of common coupling is achieved.

A Lyapunov function theory‐based nonlinear control strategy for NPC ‐type three‐level unified power quality conditioner

Zhou

Mao

et al. 2020

Summary Classic control methods commonly used for a unified power quality conditioner (UPQC) include the following: proportional integral (PI) control, proportional resonance (PR) control, and repetitive control. Generally, the main weaknesses of these control methods are poor compensation accuracy and low response speed. In this article, in order to enhance the overall performance of the system, we introduce an innovative nonlinear control strategy based on the Lyapunov function for the three‐phase three‐wire neutral‐point clamp (NPC) type three‐level UPQC. We first develop the mathematical UPQC model, then obtain from the model the control law which we use to construct the switching function by creating the Lyapunov function, thus avoiding the introduction of closed‐loop feedback. The suggested strategy also achieves system stability and dynamic performance by selecting appropriate parameters, after which a carrier‐based pulse width modulation control method based on the injected zero‐sequence component is applied to maintain the stability and balance of the DC‐side capacitor voltage. In addition, both numerical simulation and comparison of experimental results using traditional PI control, passivity‐based control methods, and sliding mode control shows that the proposed nonlinear control strategy for three‐phase three‐wire NPC type three‐level UPQC has an excellent response speed and compensation efficiency.