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Integration of Distributed Renewable Generation (DRG) to the future Smart Grid (SG) is one of the important considerations that is highly prioritized in the SG development roadmap by most of the countries including Malaysia. The plausible way of this integration is the enhancement of information and bidirectional communication infrastructure for energy monitoring and controlling facilities. However,...
Water treeing is a phenomenon whereby the polymeric cable suffers serious degradation under combined stresses of electrical, thermal and chemical, thus shortening the lifespan of the cable. A high electrical field stress present at the tip of a water tree structure would degrade the surrounding healthy polymeric insulation, leading to electrical treeing and subsequent breakdown of the water tree affected...
Under voltage load shedding (UVLS) has been successfully deployed in many systems throughout the world to protect local systems from voltage collapse. This is particularly true if the system conditions and the contingencies leading to voltage instabilities are of low probability, but would result in serious consequences. However, the locations and how much load to shed requires expert knowledge and...
Heavily loaded condition may lead to power system instability either due to sudden increase in load or tripping of adjacent transmission line. When load increases, the apparent impedance decreases accordingly depending on the nature of load, similar instances can be observed during short circuit event. In addition, the system may also experience voltage instability originating from high power flow...
Thermal rating calculation for bare overhead conductor can be done by using conductor Weather Model (WM). The critical information required in verification of the thermal rating calculation result is the conductor temperature. This paper discusses about experiments that has been conducted to verify the accuracy of the conductor temperature calculation. The experiment was also conducted to determine...
The inverse time overcurrent relay operation is based upon the current setpoint and also the time multiplier setting. Depending on the ratio of the value of the current and the setpoint current together with the value of the time multiplier setting, the amount of time delay for the trip command is determined using the inverse time characteristics. This would mean that the relay is not of the adaptive...
Power systems are usually connected in a condition where there is more than one power supply or voltage source supplying a load. These systems will have protection relays to protect various equipment connected to the system. However in isolating a fault, the direction of the fault needs to be known in order to limit the amount of loss load. This paper shall describe a possible algorithm that could...
In the time of rapid growth, there is an increase of demand for a reliable and stable power supply. Due to this, utility companies are forced to operate their power system nearer to its maximum capabilities since system expansion may be a costly option. As a result, the power system will be at risk to voltage collapse. Voltage collapse phenomenon is known to be complex and localised in nature but...
A tropical climate country experience high lightning related activities. This can be represented in terms of the keraunic level which lies within the region of 100 to 150 thunderstorm days per year. For a utility company, the high keraunic level would contribute to high possibility of power interruptions. These outages would ultimately lead to loss of revenue and reduced network reliability. These...
Short term load forecasting (STLF) is very important from the power systems grid operation point of view. STLF involves forecasting load demand in a short term time frame. The short term time frame may consist of half hourly prediction up to weekly prediction. Accurate forecasting would benefit the utility in terms of reliability and stability of the grid ensuring adequate supply is present to meet...
Sabah electricity (SESB) operates a vertically integrated electricity utility in East Malaysia. It is currently embarking on an initiative to improve the reliability of its 11 kV distribution network which is prone to trippings due to vegetation growth along their long spur lines, Apart from rentice management, another proposed solution is to install auto-reclosers (AR) at appropriate locations in...
Earlier researches have confirmed that polymeric cables suffer from serious water tree degradation under tree lengths in the affected polymeric cables are varied to assess their effect on the level of the electrical field distribution. The permittivity values within the water tree structures are varied accordingly to the lengths measured in water tree growths. The electrical field distribution waveforms...
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