Ismail Daut, Prof. Dr.
http://dspace.unimap.edu.my:80/xmlui/handle/123456789/11713
2020-08-15T12:51:07ZCurrent total harmonic reduction technique on three-level single phase transformerless photovoltaic inverter using PSpice
http://dspace.unimap.edu.my:80/xmlui/handle/123456789/50186
Current total harmonic reduction technique on three-level single phase transformerless photovoltaic inverter using PSpice
Ismail, Daut; Muhammad Irwanto, Misrun; Suhelmi; Shasidharan, Gomesh Nair; Mohd Irwan, Yusoff; Muhammad Fitra, Zambak; Risnidar, Chan Bahaudin
This paper presents simulation of three-level single phase transformerless photovoltaic
inverter (TPVI). Proposed technique of the simulation is created in PSpice software. The
simulation is constructed by two voltage controlled switches, ETABLE and EVALUE block
diagram. The voltage controlled switches produce two pulse waves with difference time
delay which influence maximum voltage angle and current total harmonic distortion
(CTHD). These two voltage pulse waves are changed become three-level AC waveform by ETABLE block with magnitude of 1 V and increased by EVALUE block which following
value of photovoltaic array voltage. The output of EVALUE block is connected to AC
loads. Resistive load of 30 W lamp and inductive load of 20 W water pump are applied to
the TPVI. The result shows that maximum voltage angle which is varied from 200 to 1800
influences the CTHD, the lowest CTHD of 11.75% is obtained when the maximum voltage
angle is 1250.
Link to publisher's homepage at http://jere.unimap.edu.my
2013-01-01T00:00:00ZTracing real and reactive power in open access network
http://dspace.unimap.edu.my:80/xmlui/handle/123456789/50158
Tracing real and reactive power in open access network
Mohd Herwan, Sulaiman; Mohd Wazir, Mustafa; Omar, Aliman; Ismail, Daut
The main objective of this paper is to present a simple and general methodology for tracing the power output of each generator to the line flows and loads through out the electrical power network. The tracing algorithm is based on basic circuit theories including superposition law, equivalent current injection and equivalent impedance. After power flow solution is obtained, the contributions of individual generators are determined through the voltages, currents, power flows and losses tracing sequentially. The veracity and accuracy of the method is demonstrated by numerical examples. Comparisons of the result with previous methods are also given.
Link to publisher's homepage at http://jere.unimap.edu.my
2008-01-01T00:00:00ZEffect of stack of transformer core lamination on losses and flux distribution in 3-phase distribution transformers 1000kVa
http://dspace.unimap.edu.my:80/xmlui/handle/123456789/50157
Effect of stack of transformer core lamination on losses and flux distribution in 3-phase distribution transformers 1000kVa
Ismail, Daut; Dina Maziana, Maiz Ahmad; Shuhaimi, Zakaria; Soib, Taib
This paper describes the results of an investigation on the effect of different amount of layers per stack of core lamination in the three of 3-phase distribution transformers 1000kVA. The investigation involves the variation of power loss, building factor, total harmonic distortion of flux and flux leakages. The power loss and flux distribution have been measured using no load test in three types of model of setting of core built from the same size and type of M5 (CRGO) laminations. The power loss of the transformer core assembled with 1 layer per stack of lamination is 6.58% better than the power loss of the transformer core assembled with 2 layers per stack of lamination and is also 8.31% better than the power loss of the transformer core assembled with 3 layers per stack of lamination, at 1.5T, 50 Hz. The flux leakage at the corner joint in the core assembled with 1 layer per stack of lamination is the lowest among the three of the transformer cores, over the whole flux density range. Total harmonic distortion flux is the largest in the transformer core with 3 layers per stack of lamination and the smallest in the transformer core with 2 layers per stack of lamination. Using 1 layer per stack of lamination in transformer core is more efficient than using the other two the three lamination of the transformer core.
Link to publisher's homepage at http://jere.unimap.edu.my
2008-01-01T00:00:00ZA critical review-power quality concerns
http://dspace.unimap.edu.my:80/xmlui/handle/123456789/50152
A critical review-power quality concerns
Anayet, Karem; Ismail, Daut; Indra, Nisja; Dina Maizana, Maiz Ahmad; Rajendran, S.
Power system quality concerns is the art and science of analyzing power system
performance within a facility to determine potential problem areas or to better understand
known problems in an electrical distribution system. This mainly explain the various types
of power disturbances such as for irritant disturbances, blinks, sags, dips, swells,
transients, impulse transients, DC offset, harmonics, notching, surges, voltage fluctuation,
flickering, spikes, phase loss, outages, interruptions, under/over voltages etc. It also
explains the impact of the disturbances for the power system operation. The emphasis has been given on data collection to understand power quality concerns. The primary sources of data collection based on technicians who spent most of their time near power system equipment. It also introduces terminology and various issues to “Power Quality”.
Link to publisher's homepage at http://jere.unimap.edu.my
2008-01-01T00:00:00Z