Research Article
Economic Impact of Low Power Factor on Institutions: a Case Study of Assosa University Building
Zelalem Bayesa Habte*
Issue:
Volume 12, Issue 3, June 2024
Pages:
48-52
Received:
20 February 2024
Accepted:
20 March 2024
Published:
11 September 2024
Abstract: Power factor is a measure of how efficiently electric power is consumed. It is the result of phase difference between voltage and current at different stages of power system. It’s the ratio of active power or useful power to apparent power. The apparent power consists of both the active power and reactive power. If the reactive power increase in a power system, the power factor becomes low. Low power factor can affect the power system quality and the consumer to suffer in paying additional penalty charge for utility if it drops below the predetermined threshold amount. In this study, the bill data record indicates there was low power factor in each month from different energy meter. The minimum or poor power factor relative to other energy meters record was 0.124035 and its power factor charge was 12,011.58 ETB which is approximately equivalent to 214.11USD. The total power factor charge for only recorded data for four months was 71,537.33ETB (1,275.17USD). The institution is paying unwanted charge that can be improved by using power factor correction capacitor. The reactive power (kVAR) required to correct the power factor to 0.9 have been computed in this paper. The money expended for low power factor will be saved and the system’s power quality increase as well.
Abstract: Power factor is a measure of how efficiently electric power is consumed. It is the result of phase difference between voltage and current at different stages of power system. It’s the ratio of active power or useful power to apparent power. The apparent power consists of both the active power and reactive power. If the reactive power increase in a ...
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Research Article
Optimization for Spectral and Power Characteristics of Bicolour LED Driver
Fouzia Ferdous*,
ABM Harun-ur Rashid
Issue:
Volume 12, Issue 3, June 2024
Pages:
53-61
Received:
9 August 2024
Accepted:
2 September 2024
Published:
20 September 2024
Abstract: LED-powered luminaires have the ability to offer cutting-edge features like temperature adjustment and color management. Color shift creates discomfort in human eyes. So it is essential to design a LED driver which will precisely control the color parameters of the LED driver. Precise control of color parameters like CRI, CCT, color intensity is very complex and challenging. This paper describes the nonlinear optimization methodology for the design of blended LED light sources. This paper presents the methodology that enables LED strings regarding various parameters, e.g. high color rendering index (CRI) and high luminous efficacy of a blended bi-color (namely red CCT-2500K and blue CCT-9000K) LED driving system. Due to the applied optimization, the obtained CRI is maintained 98.03%. The overall luminous intensity depends upon the combined luminous flux which depends upon the current control of both LED sources. These optimized LED currents ensure the desired CCT. The achieved luminous efficacy is 90% at two optimal peak wavelengths 601 nm and 426 nm respectively. Power loss is minimized by frequency optimization. At the same time power parameters i.e. low THD and high P. F. is also maintained. The nonlinear optimization is verified in Ltspice simulations and experimentally for two different luminaire strings.
Abstract: LED-powered luminaires have the ability to offer cutting-edge features like temperature adjustment and color management. Color shift creates discomfort in human eyes. So it is essential to design a LED driver which will precisely control the color parameters of the LED driver. Precise control of color parameters like CRI, CCT, color intensity is ve...
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