scholarly journals Design and Construction of a Low-Cost Automatic Single-Phase Transfer Switch

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Abiodun E Amoran ◽  
Gerald K Ijemaru ◽  
Olaitan Akinsanmi ◽  
Watson Agbramu
Keyword(s):  
Liquid Crystal ◽  
Power Supply ◽  
Single Phase ◽  
Phase Transfer ◽  
Liquid Crystal Display ◽  
Power Source ◽  
Phase System ◽  
Alternative Source ◽  
Automated Method ◽  
Switch Power

Irregular power supply poses a serious problem in many developing countries with power outage usually experienced on a regular basis. Thus, this challenge necessitates the need for an automated method of power change over to an alternative source during power failure that will be an improvement over the manual change over system. This study aims to design and construct a microcontroller-based Automatic Transfer Switch (ATS) for a single-phase system. Atmega8 microcontroller was programmed to automatically switch power supply between a primary source and a secondary power source through the aid of relays. A modular approach was used in the design of this ATS, which incorporates Atmega8 microcontroller, diodes, resistors, L7805 voltage regulator, PC817 optocouplers, a buzzer alarm, NPN transistors, and a Liquid Crystal Display (LCD) that indicates which power source was available. This design is limited to 30A on full loading due to the power relay used in the design. The testing showed that the design was able to automatically switch power between two supply sources with no external aid and it performed optimally even when loaded to 90% of its maximum bearing-capacity.Keywords: Automatic Transfer Switch, Atmega8 Microcontroller, Liquid Crystal Display, NPN Transistors, PC817 Optocouplers, Relays

scholarly journals High-bandwidth buffer amplifier for liquid crystal display applications

2017 ◽  
Vol 30 (4) ◽  
pp. 549-556
Author(s):  
Saeed Sadoni ◽  
Abdalhossein Rezai
Keyword(s):  
Liquid Crystal ◽  
Power Consumption ◽  
Performance Feedback ◽  
Power Supply ◽  
High Performance ◽  
Liquid Crystal Display ◽  
Feedback Circuit ◽  
High Bandwidth ◽  
Buffer Amplifier ◽  
Simulation Results

In this paper, a novel high-bandwidth and low-power buffer amplifier is presented for the liquid crystal display applications. This buffer amplifier consists of a folded cascade differential amplifier in the input and a class-amplifier in the output, which are designed carefully. The proposed buffer amplifier utilizes a high-performance feedback circuit to increase the bandwidth. It also utilizes a comparator circuit to avoid wasting power. The designed circuit has been simulated in 180nm technology using HSPICE 2008.3. The simulation results show that the bandwidth, power consumption and power supply of the designed circuit are 1.14MHz, 1.64mW and 1.8V, respectively.

scholarly journals Implementation of Single Phase SRF based Dynamic Voltage Restorer in Distribution System for Power Quality Improvement

2019 ◽  
Vol 8 (12) ◽  
pp. 3451-3456
Keyword(s):  
Power Quality ◽  
Power Supply ◽  
Single Phase ◽  
Positive Sequence ◽  
Voltage Sag ◽  
Phase System ◽  
Major Power ◽  
Dynamic Voltage Restorer ◽  
Voltage Restorer ◽  
Dynamic Voltage

Power Quality (PQ) is becoming an important issue as the increase in electricity use continues. Reduction in the quality of electrical power is due to various kinds of voltage related problems such as voltage sag, voltage swell, short-lived interruptions, harmonic distortions, notches, flickers, spikes and transients. The major power quality problems in single phase system are voltage sag and harmonics. The Mitigation of voltage sag and harmonics in single phase system under the distorted power supply situations was effectively eliminated with Dynamic Voltage Restorer (DVR). The single-phase SRFT (Synchronous Reference Frame Theory) was implemented in the controller design for DVR. DVR will produce required amount of instantaneous voltage to be injected. Designed controller technique will utilize the function of Moving Average Filter (MAF) for getting the fundamental quantity of positive sequence component from the disturbed supply voltage. Experimental results of DVR prove its effectiveness to mitigate voltage sag and harmonics during disturbed power supply condition.

Integrated DC-AC Inverter for Hybrid Power System

2015 ◽  
Vol 793 ◽  
pp. 252-256
Author(s):  
Abadal Salam T. Hussain ◽  
Qais H. Jeflawi ◽  
F. Malek ◽  
Israa A. Dahham ◽  
Jailani O. Mahmoud ◽  
...  
Keyword(s):  
Intelligent Control ◽  
Power Supply ◽  
Power Supply System ◽  
Single Phase ◽  
Sine Wave ◽  
Power Source ◽  
Supply System ◽  
Information And Communications Technology ◽  
Wave Power ◽  
Ac Power

A 300 W/ 50 Hz single-phase sine wave with a 555 timer IC controller was designed, simulated, implemented and tested to investigate output AC power quality. An input 12 VDC power supply, which simulates PV-Wind power source, was connected to the inverter circuit and charge-discharge energy storage was also studied. Results of simulation show that as well as the experiment result is obtained.This paper is present the advantage ofhybrid system wind &solar together in power supply system from the integration between time andlocation. It showsthe evolution of wind-solar in single-phase sine wave power inverter and provides the structure of information and communications technology and equipment.Some main techniques such as the circuit topology and operation modes of the key link, algorithm of the intelligent control charging and discharging and so on.

scholarly journals Analisa Perancangan Filter LCL Pada Penyearah PWM Satu Fasa Full Bridge

2017 ◽  
Vol 1 (2) ◽  
Author(s):  
Hari Anna Lastya
Keyword(s):  
Direct Current ◽  
Power Supply ◽  
Single Phase ◽  
Alternating Current ◽  
Power Source ◽  
The Other ◽  
Lcl Filter ◽  
The Third ◽  
Pwm Rectifiers

Electronics devices need a direct current power supply although now only one alternating current power supply is available. Therefore, ac-dc converters which can convert an alternating current power supply to a direct current power supply will be needed. However, the use of this ac-dc converters will cause distortion in the form of current waves which are called harmonics. This harmonics can fault the work of the other electric devices which are attached to the same power source. Therefore, it is recommended that the harmonics generated by rectifiers should be under IEC 61000-3-2 standard. In this research will the reduction of harmonics by using LCL filter. At load of 2 kW, R of 5 , L of 0,05 H at PWM rectifiers single phase full bridge with RL load produce the third harmonics current of 2.57 amperes, the installed LCL filter produces the third harmonics current of 1.26 amperes. According to IEC-61000-3-2 standard, the allowed third harmonics current is 2.3 amperes.

scholarly journals Dielectric properties and molecular motions of liquid crystal molecules in 4-(2-methylbytyl)phenyl 4-(4-octylphenyl)benzoate liquid crystal having blue phase (CE8)

2015 ◽  
Vol 33 (2) ◽  
pp. 418-429
Author(s):  
W. Otowski ◽  
G. Lewińska
Keyword(s):  
Molecular Dynamics ◽  
Liquid Crystal ◽  
Liquid Crystalline ◽  
Liquid Crystal Display ◽  
Phase System ◽  
Component System ◽  
Chiral Nematic ◽  
Phase Liquid ◽  
Blue Phase ◽  
Multi Component System

AbstractBlue phase liquid crystals exhibit unique properties which are used in the new type of display. A blue-phase liquid crystal display was first presented commercially by Samsung in 2007. The blue-phase-three-color pixel display eliminates the need for color filters. This type of display uses blue-phase multi-component liquid crystal. Considering the one-component systems, it turns out that they are stable only in a very narrow range of temperatures between the isotropic and the chiral nematic phase (about 1 K). In 2005, a wide temperature range BP multi-component system was reported by researchers from the University of Cambridge. There are still several unsolved problems left. One of them is chemical stability and reliability. Therefore, the knowledge of molecular dynamics of blue phase liquid crystal is a prerequisite for understanding of blue-phase multi-component system. Understanding the molecular dynamics of a single component liquid-crystalline blue phase system can facilitate the solution of these problems. We present the molecular dynamics investigation of 4-(2-methylbytyl)phenyl 4-(4-octylphenyl)benzoate (CE8), which may be a good candidate to form materials suitable for blue-phase liquid crystal displays.

Effect of Maximum Voltage Angle on Inverter Performance Applied in Uninterrupted Power Supply (UPS)

2015 ◽  
Vol 793 ◽  
pp. 304-308
Author(s):  
Mahrizal Masri ◽  
R. Badlisha ◽  
Muhamad Irwanto ◽  
N. Gomesh ◽  
Y.M. Irwan ◽  
...  
Keyword(s):  
Power Supply ◽  
Single Phase ◽  
Negative Impact ◽  
Harmonic Distortion ◽  
Power Source ◽  
Phase Inverter ◽  
Uninterrupted Power Supply ◽  
Aquarium Water ◽  
Single Phase Inverter ◽  
Maximum Voltage

Uninterrupted power supply (UPS) sits between a power supply such as wall outlet and devices to prevent undesired feature that can occur within the power source such as outages, sags, surges and bad harmonics from the supply to avoid a negative impact on the devices. This paper presents a photovoltaic (PV) powered UPS using microcontroller PIC16F628A-I/P. It is a standby UPS whereas if the main power source fails to supply power to loads, a battery powered inverter turns on to continue supplying power. The battery is charged by the PV using solar charger and transfer switch controlled by the microcontroller. In this research, AC three-level waveform single phase inverter was developed and created by a microcontroller PIC16F627A-I/P with varied maximum voltage angle from 200 to 1800 and tested to a load of 240 V, 20 W AC aquarium water pump, and also analyzed effect of maximum voltage angle on the three-level single phase inverter performance. The result showed that maximum voltage angles of the inverter effected on root mean square value of AC voltage, current and power. If the maximum voltage angle was increased, therefore value of the AC voltage, current and power would increase. The maximum voltage angle would effect on the current total harmonic distortion (CTHD), the lowest CTHD of 15.448% was obtained when the maximum voltage angle was 1340.

Sign in / Sign up

Export Citation Format

Share Document