Transient Power Quality Performance of Multi Photovoltaics using MPPT P and O/MPPT Fuzzy

The overrun of transient power quality index caused by the large-capacity electric arc furnace (EAF) has become a prominent problem affecting the safe and stable operation of the power system. (1) In this paper, the relationship between arc furnace volt-age and current is derived based on the different stages of arc combustion, and the random variation of chaotic phenomenon of the arc voltage are simulated. Established an EAF model suitable for the study of transient power quality problems. (2) Take 50t AC EAF as an example to analyze the reactive power impact and the influence on the point of common coupling (PCC) voltage caused by the three-phase short circuit of the electrode. The results show that the experimental results are consistent with the theoretical analysis, verifying the correctness and effectiveness of the model. (3) When the three-phase short-circuit occurs, the reactive power impact is nearly 6 times that of normal operation, the short-circuit current is 2.66 times that of normal operation, and the effective value of the PCC voltage has dropped by 40.37%, which provides a theoretical basis for real-time compensation of impulsive reactive power and improvement of the transient power quality of the EAF.

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Particle swarm optimization algorithm-based PI inverter controller for a grid-connected PV system

PLoS ONE ◽

10.1371/journal.pone.0243581 ◽

2020 ◽

Vol 15 (12) ◽

pp. e0243581

Author(s):

M. F. Roslan ◽

Ali Q. Al-Shetwi ◽

M. A. Hannan ◽

P. J. Ker ◽

A. W. M. Zuhdi

Keyword(s):

Power System ◽

Power Quality ◽

Transient Response ◽

Particle Swarm ◽

Pi Controller ◽

Pv System ◽

Quality Performance ◽

Three Phase ◽

Input Parameters ◽

Utility Grid

The lack of control in voltage overshoot, transient response, and steady state error are major issues that are frequently encountered in a grid-connected photovoltaic (PV) system, resulting in poor power quality performance and damages to the overall power system. This paper presents the performance of a control strategy for an inverter in a three-phase grid-connected PV system. The system consists of a PV panel, a boost converter, a DC link, an inverter, and a resistor-inductor (RL) filter and is connected to the utility grid through a voltage source inverter. The main objective of the proposed strategy is to improve the power quality performance of the three-phase grid-connected inverter system by optimising the proportional-integral (PI) controller. Such a strategy aims to reduce the DC link input voltage fluctuation, decrease the harmonics, and stabilise the output current, voltage, frequency, and power flow. The particle swarm optimisation (PSO) technique was implemented to tune the PI controller parameters by minimising the error of the voltage regulator and current controller schemes in the inverter system. The system model and control strategies were implemented using MATLAB/Simulink environment (Version 2020A) Simscape-Power system toolbox. Results show that the proposed strategy outperformed other reported research works with total harmonic distortion (THD) at a grid voltage and current of 0.29% and 2.72%, respectively, and a transient response time of 0.1853s. Compared to conventional systems, the PI controller with PSO-based optimization provides less voltage overshoot by 11.1% while reducing the time to reach equilibrium state by 32.6%. The consideration of additional input parameters and the optimization of input parameters were identified to be the two main factors that contribute to the significant improvements in power quality control. Therefore, the proposed strategy effectively enhances the power quality of the utility grid, and such an enhancement contributes to the efficient and smooth integration of the PV system.

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Classification of transient power quality disturbance based on S-transform and fuzzy KNN

Proceedings of the 4th International Conference on Mechatronics, Materials, Chemistry and Computer Engineering 2015 ◽

10.2991/icmmcce-15.2015.205 ◽

2015 ◽

Author(s):

Hong Men ◽

Jia Liu ◽

Yilong Hao ◽

Chunlai Li

Keyword(s):

Power Quality ◽

S Transform ◽

Power Quality Disturbance ◽

Transient Power Quality

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Time-Frequency Analysis Method in the Transient Power Quality Disturbance Analysis Application

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.700.99 ◽

2014 ◽

Vol 700 ◽

pp. 99-102

Author(s):

Meng Da Li ◽

Yu Bo Duan ◽

Yan Wang

Keyword(s):

Power Quality ◽

Signal Interference ◽

Time Frequency ◽

Quality Signal ◽

Power Quality Disturbance ◽

Analysis Application ◽

Disturbance Analysis ◽

Realistic Significance ◽

Transient Power Quality

This paper uses the method of S transformation to test the starting time, the end of the time, frequency and amplitude characteristics of common transient power quality signal disturbance. Through error analysis and simulation show that this method can accurately determine the disturbance occurred time and duration, and the identification and determination of disturbance can be simple and intuitive. It has the practical value and realistic significance to power quality signal interference analysis.

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