Hasmaini Mohamad

A New Under-Frequency Load Shedding Technique Based on Combination of Fixed and Random Priority of Loads for Smart Grid Applications

This paper presents a new under-frequency load shedding technique based on the combination of random and fixed priority of loads. It has been observed that placing all of the loads in the distribution system with fixed priority results in un-optimum load shedding. On the other hand, designing the load priority with a combination of random and fixed priority provides the technique with some sort of flexibility in achieving the optimal load shedding. The validation of the proposed scheme on different scenarios proves that the proposed technique is capable of achieving the optimal load shedding and recovering frequency to nominal value without any overshoot.

A fuzzy based load frequency control for distribution network connected with mini hydro power plant

Mini hydro power plants MHPP are gaining attraction as a cost effective source for rural electrification in developing countries due to its environmental friendly operation. These MHPP plants suffer from the speed control problem due to continuous load variation. PID controllers fail to provide optimum speed control due to its limitation of parameter tuning. Alternatively, Fuzzy logic control is commonly used for implementing intelligent control for the nonlinear system. This paper presents a new fuzzy logic based governor for frequency/speed regulation of MHPP for implementation in distribution network. For verification, the response of load frequency control using fuzzy based governor and PID based governor is compared. The simulation results show that fuzzy based governor ensures robust control by improving the frequency response as well as dynamic response in comparison to PID based governor. Furthermore, fuzzy based governor enables the generator to continuously supply power even at 25% load variation whereas generator with PID based governor fails to supply power even at 20% load variation.

A Sensitivity Analysis of Different Power System Parameters on Islanding Detection

This work analyzes the sensitivity of 16 power system parameters that can be used in passive techniques to detect islanding and nonislanding events. It is observed that the rate of change of frequency over reactive power (df/dq) can effectively detect minute disturbances in power supply. It is also shown that active and reactive power mismatch has an opposing effect on the variation of frequency (df) in real time environment. As a result of this, a new passive technique based on df/dq is proposed. The simulation results indicate that the proposed technique is able to distinguish islanding from other events of similar signatures, such as load variation, capacitor switching, faults, and induction motor starting.

Locating fault using voltage sags profile for underground distribution system

This paper presents an alternative fault location algorithm to estimate short-circuit faults location in electrical distribution networks using only voltage sags data. The proposed algorithm uses voltage sags profile as a means to locate fault. The possible fault locations is estimated by incorporating the measured voltage sags magnitude and its corresponding phase angle into an equation of voltage sag as a function of fault distance. A ranking procedure is also introduced to rank possible fault locations due the same electrical distance. The uncertainty of fault resistance is also considered in this algorithm. The performance of the technique is presented by testing it using an actual underground distribution network. The simulation results indicated a possibility of practical implementation.

Evaluation on non-detection zone of passive islanding detection techniques for synchronous distributed generation

An effective islanding detection technique is extremely important in safeguard Distributed Generation (DG) from incur a great impact due to unintentional islanding. Among commonly employed techniques, passive detection is known as the simplest and cheapest detection technique, but suffers large Non-Detection Zone (NDZ). This paper present an evaluation on NDZ of passive islanding detection technique based on the combination of passive techniques i.e Rate of Change of Frequency (ROCOF) and Rate of Change of Voltage (ROCOV). The NDZ is identified by performing simulation study on a distribution system. A systematic approach to locate the specific zone is carried out by varying active and reactive power imbalance at the Point of Common Coupling (PCC) when the system is subjected to islanding. The performance of combination technique is compared with Over/Under Frequency (OUF) and Over/Under Voltage (OUV). The results show the combination technique has a smaller NDZ and is capable to detect islanding within a shorter time.

Feasibility study of an intentional islanding operation with a new adaptive load shedding

Intentional islanding operation has recently been considered by some utilities to effectively use the available renewable energy generation. In this paper, an intentional islanding operation of hydro Distributed Generation (DG) is proposed. Governor and Automatic Voltage Regulation (AVR) are properly developed such that the DG exhibits a good dynamic response once a part of the network is islanded. A new adaptive load shedding scheme is also proposed to address the issue of overload or insufficient generation after the system is islanded. The scheme is based on a combination of adaptive and intelligent techniques. The disturbance magnitude of response based and event based is treated differently: 1) event based is based on the power imbalance 2) response based is based on the swing equation which relies on the frequency and Rate of Change of Frequency measurement. To investigate the effectiveness of the controller and the load shedding scheme, dynamic simulation on an intentional islanding operation is performed on an existing Malaysia network interconnected with mini hydro generation. The simulation results demonstrate that the island is successfully established with the frequency and voltage response during the islanding operation are within the acceptable limit.

A new technique for islanding operation of distribution network connected with mini hydro

An islanding operation of a distribution network is a topic of interest due to the significant penetration of distributed generation (DG) in a power system network. However, controlling the frequency of an islanded distribution system remains an unresolved issue, especially when the load exceeds the generation. This paper presents a new technique for a successful islanding operation of a distribution network connected with multiple mini hydro based DGs. The proposed technique is based on three main parts. The first part uses an islanding detection technique to detect the islanding event correctly. The second part consists of a power imbalance estimation module (PIEM), which determines the power imbalance between the generation and load demand. The third part consists of a load shedding controller, which receives the power imbalance value and performs load shedding according to load priority. The proposed technique is validated on an 11 kV existing Malaysia distribution network. The simulation results show that the proposed technique is effective in performing a successful islanding operation by shedding a significant number of loads.

Energy saving analysis of a 16kWp grid connected photovoltaic (PV) system at Green Energy Research Centre (GERC), UiTM Shah Alam

This paper presents analysis of energy saving made by 16kWp grid connected photovoltaic (PV) system at Green Energy Research Centre (GERC), UiTM Shah Alam. The study is based on data collected from the PV system from May 2012 until April 2013. The data consists of solar irradiance, ambient and module temperature and output power of the PV system. The research investigates the effect of the PV system on the GERC buildings daily load curve and maximum demand using the concept of residual load. The energy saving based on TNB tariff is compared with the revenue if the energy from the PV system would be sold to national grid at the FiT tariff. The CO2 emission avoidance provided by the PV system is also calculated. Analysis shows that there were strong correlation between the solar irradiance, ambient temperature and module temperature with the energy from the PV The energy from the PV reduced the daily energy consumption by 28.34% during the weekday. Total energy saving by the PV over the duration considered was 20,679.28kWh and this saved RM9,827 of electricity bill. On the other hand, if the energy from the PV would be sold to the utility grid, the expected payback period on the investment is 11 year.

Under-frequency load shedding technique considering response based for islanding distribution network connected with mini hydro

One of the biggest challenge in an islanding operation is to sustain the frequency stability. A large power imbalance following islanding would cause under-frequency, hence an appropriate control is required to shed certain amount of load. Under-frequency load shedding (UFLS) scheme is commonly adopted for grid transmission system of which requires particular consideration for application on an isolated/islanded system. The main objective of this research is to develop an adaptive UFLS technique for an islanding system. The technique is designed considering response based for any disturbance during islanding operation. The disturbance magnitude is determined from the swing equation in which relies on frequency and rate of change of frequency measurement for shedding the required amount of load. The technique is modeled by using PSCAD simulation tool. A simulation study on a distribution network connected with mini hydro generation is carried out to evaluate the UFLS model. It is performed under different load condition: peak load, base load and overload scenario. The results have shown that the load shedding technique have successfully shed certain amount of load and stabilized the system frequency following overload.

IMLANNs for Congestion Management in Power System

Received Mar 3, 2018 Revised Apr 11, 2018 Accepted Apr 21, 2018 Paintball has gained a huge popularity in Malaysia with growing number of tournaments organized nationwide. Currently, Ideal Pro Event, one of the paintball organizer found difficulties to pair a suitable opponent to against one another in a tournament. This is largely due to the manual matchmaking method that only randomly matches one team with another. Consequently, it is crucial to ensure a balanced tournament bracket where eventual winners and losers not facing one another in the very first round. This study proposes an intelligent matchmaking using Particle Swarm Optimization (PSO) and tournament management system for paintball organizers. PSO is a swarm intelligence algorithm that optimizes problems by gradually improving its current solutions, therefore countenancing the tournament bracket to be continually improved until the best is produced. Indirectly, through the development of the system, it is consider as an intelligence business idea since it able to save time and enhance the company productivity. This algorithm has been tested using 3 size of population; 100, 1000 and 10,000. As a result, the speed of convergence is consistent and has not been affected through big population.N. N. S. Abdul Rahman, N.M. Saad, A. R. Abdullah, M. R. M. Hassan, M. S. S. M. Basir, N. S. M. Noor 1,2,4,6Faculty of Electronic and Computer Engineering, Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, 76100 Durian Tunggal, Melaka, Malaysia 2,3Center for Robotics and Industrial Automation, Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, 76100 Durian Tunggal, Melaka, Malaysia 3,5Faculty of Electrical Engineering, Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, 76100 Durian Tunggal, Melaka, MalaysiaLight rail transit (LRT), or fast tram is urban public transport using rolling stock similar to a tramway, but operating at a higher capacity, and often on an exclusive right-of-way. Indonesia as one of developing countries has been developed the LRT in two cities of Indonesia, Palembang and Jakarta. There are opinions toward the development of LRT, negative and positive opinions. To reveal the level of LRT development acceptance, this research uses machine learning approach to analyze the data which is gathered through social media. By conducting this paper, the data is modeled and classified in order to analyze the social sentiment towards the LRT development.Mohamad, S., Nasir, F.M., Sunar, M.S., Isa, K., Hanifa, R.M., Shah, S.M., Ribuan, M.N., Ahmad, A. 1,4,6,7,8Faculty of Electrical and Electronic Engineering, Universiti Tun Hussein Onn Malaysia, Johor, Malaysia 1,2,3UTM-IRDA Digital Media Centre, Media and Game Innovation Centre of Excellence, Universiti Teknologi Malaysia, Johor, Malaysia 1,2,3Faculty of Computing, Universiti Teknologi Malaysia, Johor, Malaysia 5Centre for Diploma Studies, Universiti Tun Hussein Onn Malaysia, Johor, Malaysia 6Research Centre for Applied Electromagnetics, Universiti Tun Hussein Onn Malaysia, Johor, MalaysiaReceived Jan 31, 2018 Revised Apr 21, 2018 Accepted Apr 30, 2018 Bluetooth is an emerging mobile ad-hoc network that accredits wireless communication to connect various short range devices. A single hop network called piconet is the basic communication topology of bluetooth which allows only eight active devices for communication among them seven are active slaves controlled by one master. Multiple piconets are interconnected through a common node, known as Relay, to form a massive network called as Scatternet. It is obvious that the performance of Scatternet scheduling is highly dependent and directly proportionate with the performance of the Relay node. In contrary, by reducing the number of Relays, it may lead to poor performance, since every Relay has to perform and support several piconet connections. The primary focus of this study is to observe the performance metrics that affects the inter-piconet scheduling since the Relay node’s role is like switch between multiple piconets. In this paper, we address and analyze the performance issues to be taken into consideration for efficient data flow in Scatternet based on Relay node.