Harmonics Analysis of Inverter Circuits on Smart Grid System

Smart Grid System has Harmonics Distortions. Caused when switching inverters convert DC current into AC that lowers power quality and affects power generation system. Interference occurs in sinusoidal wavelengths of voltage or system currents that have frequency multiples of fundamental frequencies. Therefore, analysis is required based on IEEE Std 519-2014 standard which is for 20kV Bus voltage has a limit value of 3% for VIHD and 5% for VTHD, using ETAP software was conducted simulating the condition of the non-grid bus system has a VTHD value of 4.9%, while the on-grid system conditions that have inverters for buses have a VTHD value of 5.81%, and simulations before passive filters are installed in the 5th order (f = 250 Hz) with a VTHD value of 6.33%; VIHD 4.82% after installing passive filter VTHD value 1.88 %; VIHD 0.00 %, while in the 7th order (f=350 Hz) the VTHD value is 6.33%; VIHD3.33 % after installing passive filter VTHD value 1.88%; VIHD 0.00%. The passive filter used is a single tuned passive filter. Change the PF (Power Factor) value before filtering is installed on the distribution bus = 82.9%, after the passive filter installed is 88.1%.

Simulation of passive filter design to reduce Total Harmonic Distortion (THD) in Energy-Saving Lamps (LHE) and Light Emitting Diodes (LED)

This paper discusses the design of a passive filter system for Energy-Saving Lamps (LHE) and Light Emitting Diodes (LED) using the MATLAB Simulink software. This type of lamp is a type of non-linear load that produces harmonics of current and voltage. However, this harmonic problem can be reduced using passive filters. To determine the size of the passive filter components, research was carried out in the form of measurements of power, power factor, voltage, current, THDi and THDv produced by the LHE and LED. The results of these measurements were simulated using MATLAB Simulink to determine the passive filter design that reduces the THD value on the LHE and LED. To reduce the level of current harmonics, a single tuned LC passive filter was designed. The filter, designed to work at a frequency of 50 Hz and is expected to reduce the level of harmonics in the 3rd, 5th, 7th, 9th, 11th harmonic orders so that the THD produced by LHE and LED meets the IEEE 519-2014 standards. The simulation results of single tuned LC passive filter design can reduce THDi by 46.78% from the initial THD of 84.55% so that it becomes 37.77%.

Exponential passive filter design for switched neural networks with time-delay and reaction-diffusion terms

This paper investigates the problem of exponential passive filter design for switched neural networks with time-delay and reaction-diffusion terms. With the aid of a suitable Lyapunov–Krasovskii functional and some inequalities, a linear matrix inequality-based design method is developed that not only makes the filtering error system exponentially stable but also forces it to be passive from external interference to output error. Then, the filter design is extended to the complex-valued case via separating the system into real-valued and complex-valued parts. Finally, a numerical example is utilized to illustrate the effectiveness of the filter design methods for the real-valued and complex-valued cases, respectively.

An Experimental Analysis of Harmonic Distortion Indices In Home Based Electrical Appliances and Improvement Using Passive Filter

Nowadays, the growing use of non-linear loads in home appliances gives rise to harmonic pollution in the electrical power distribution system, which degrades the power quality. Many domestic appliances have power electronic converters that characteristically draw a non-sinusoidal current waveform. Short-term effects of non-linear appliances are causing malfunction and damage of electronic devices and long-term effects are thermal losses in equipment and cable, hasty aging, and reduced life period of devices. The whole impact depends on the power ratings and quantity of electrical appliances and their harmonic diversity. Usually, the existence of harmonics and their effects in a domestic zone are not monitored as compared to the industrial and commercial sectors. To ensure the quality of power, it is necessary that a harmonic study is carried out to identify the details of harmonic pollution that is polluting sources, the parameters or quantities they pollute in each instance, and effective improvement methods. In this paper, experimental analysis was performed which focuses on traditional single-phase home-based electrical appliances causing the quality of power down, and implementation of the passive filter is suggested for improvement in the quality of power. All experimental harmonic distortion measurements of home-based electrical appliances were performed in the power electronic laboratory of QUEST Nawabshah. Harmonic distortion indices measurements of home-based electrical appliances have been taken using the fluke power quality Analyzer (PQA) instrument. The analysis shows that from many types of loads, switch mode power supply (SMPS) based load is rich in harmonic distortion. Therefore, an equivalent model of SMPS load in MATLAB/Simulink is developed to analyze improvement in power quality by designing and implementation of the passive filter. The outcome of this research work will be helpful to make the source current sinusoidal by reducing harmonic distortion and thus improve the power quality.

A Method for Designing and Optimizing the Electrical Parameters of Dynamic Tuning Passive Filter

Power electronics-based apparatuses absorb non-sinusoidal currents. These are considered non-linear and non-symmetrical loads for the power grid, and they generate a harmonic current. The dynamic tuning passive filter (DTPF) is one of the best solutions for improving power quality and filtering out harmonic currents to get a symmetrical current waveform. The electrical parameters of DTPF can influence its absorbing harmonic current, tuning performance, and cost. In this paper, a method for designing and optimizing the electrical parameters of dynamic tuning passive filter is proposed in order to improve the effectiveness of DTPF and the symmetry level of the power source. First, according to the characteristics of the harmonic source, the design technical indicators of DTPF, and its topology, the design procedure for the electrical parameters of DTPF is proposed. Second, based on detailed analysis of the test results, the range of the harmonic current absorption coefficient is determined. Third, the range of the relationship coefficient is determined by analyzing the impact of the filter capacitor’s capacity on the filter performance. Fourth, the calculation method for the electrical parameters of DTPF is devised. Finally, the validity of this method is verified by several engineering cases, and the electrical parameters of the filter capacitor and electromagnetic coupling reactance converter (ECRC) under the lowest total cost are simulated and optimized. Our approach can optimize the electrical parameters of DTPF and improve the harmonic suppression effectiveness, thus leading to a more symmetrical waveform and successfully avoiding power grid problems. The research results of this study not only provide a basis for the design of ECRC, but also lay a foundation for the machining DTPF.