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As technology advanced, electrical interruption or disturbance still becomes a significant problem in power systems. A fault is one example of electrical disturbance or power failure in a power system. In order to recover the system, the fault must be detected, classify and locate to eliminate as fast as possible. Four types of fault occur in the transmission line. Those four types are Line-to-Ground Fault (L-G), Line-to-Line Fault (L-L), Double Line-to-Ground Fault (L-L-G), and Three Line Fault (L-L-L). These Days, fault has been one of the significant problems in the transmission line system. Fault can lead to power losses in transmission lines as well as power failure. Electrical service in the transmission line system needs to be recovered immediately after fault appears to avoid more energy losses. Thus, it is crucial to create a system that will detect and eliminate fault faster, more accurately, and effectively. Typically, transmission line fault classification required complex signal processing, required expert knowledge, and complex mathematical modeling to process the output signal. This paper proposed a deep learning technique to classify ten types of fault through simulation. The objective of this study is to propose automated signal processing and features extraction. This technique can model a system that generates the automated signal processing and extract features learning with a deep learning framework and classify all the ten fault types in transmission lines accurately and effectively.

Dual-power PV-grid system was introduced to manipulate the lower tariff rate at off-peak period and to reduce the capital installation cost of PV energy system. The power converter system consists of a boost regulator to boost and regulate PV outputs to fixed voltage of 240V, 50Hz, a maximum power point tracking (MPPT) to derive maximum power from PV panels and a three operation modes of the battery converter to regulate charging current/discharging current under various PV output and load variation. The system utilizes 25 levels of cascaded multilevel inverter to invert DC voltage from solar panel to AC voltage. The operation and the synchronization of the power converter system was digitally controlled to ensure the system works at maximum captured power, fast switching with minimum losses, and produces fixed 240 V, 50Hz power supply in variation of environmental conditions. In this paper, the control strategy implemented in the power converter system in the dual-power PV-grid energy system are described and discussed.

This paper focuses on a Grid-Connected Photovoltaic (GCPV) system of amorphous Silicon (a-Si) PV module technology with total PV capacity is about 1.179 kWp. This a-Si FS GCPV system is located near to the Green Energy Research Centre (GERC) Building at Universiti Teknologi MARA (UiTM) Shah Alam, Malaysia. This a-Si FS GCPV system installation was referred to Malaysian Standard MS1837:2010 and designed based on initial data values. These days, various of the GCPV system applications in Malaysia using thin-film PV module technology was designed at stabilised data values. So, this a-Si PV system is conducted to study the PV performances and behaviors under Malaysia's perspective. After the observation period, a-Si FS GCPV system performs in good condition. The PV system generated 644.40 kWh electrical energy during the first six months of operation (June-December 2011) and the average daily energy yield of 3.03 kWh. The average monthly final yield was found to be 78.0 kWh/kWp, while the range of the initial/stabilized performance ratios between 55.8% to 78.2% and 73.0% to 102.4%.

Dual-power PV-grid system was introduced to manipulate the lower tariff rate at off-peak period and to reduce the capital installation cost of PV energy system. In this paper, the system and simulation design of the system is discussed to evaluate the design parameters which affect the design performance of the power converter. It consists of a boost regulator to boost and regulate PV outputs to fixed voltage of 240V, 50Hz, a MPPT to derive maximum power from PV panels and a three operation modes of the battery converter to regulate charging current/discharging current under various PV output and load variation. The system utilizes 15 levels of cascaded multilevel inverter to invert DC voltage from solar panel to AC voltage. The simulation results certify the simulation model can emulate the real system.

This paper presents a modelling of Multiple Input-Single Output (MISO) model for tracking maximum point of Photovoltaic (PV) Systems. A system identification approach is used to obtain the model characteristics of existing structural systems through dynamic observations which incorporate with traditional direct control Maximum Power Point Tracking (MPPT) algorithm. The generate model characteristics was used in designing the MPPT of the Photovoltaic Systems. The need of an efficient mathematical model to characterize the dynamics system for PV is essential for implementing the system for control applications. In this paper, the transfer function relating the input parameters (Solar irradiance and cell temperature) and output parameter (DC current) of the PV module MF120EC3 was identify with the aid of MISO for Auto-Regressive with eXogenous input (ARX) model. The approach has concern on the estimation of the (Direct Current (DC) for photovoltaic system based on the real systems data from Pusat Tenaga Malaysia (Malaysia Energy Centre, MEC). A Fourth-order autoregressive (ARX) model using the ARX algorithm, (ARXQS) was chosen since the model output provide 93.42% best fit model criteria. The modelling is implemented using system identification toolbox of Matlab software.

This paper discussed the current status of a grid-connected photovoltaic (PV) system installed in Malaysia. There are 97 locations with capacity of array power, which is 857.92 kWp grid-connected PV systems are monitored by the Photovoltaic System Monitoring Centre (PVSMC), UiTM. Since monitoring the performances for grid-connected system, there are several sites had been detected facing problems involve technical problem like an inverter fault, sensor fault and environmental problem such as shading effect and lower energy. All the problem will be affected the PV system performances in terms of final yield and performance ratio thus it will be inclined the data availability problem. Furthermore, it could waste the energy produced by PV array and energy payback period. An established practical knowledge in designing a PV system need to be taken seriously in order to avoid improper design before installation to maximize the energy production. It is very important to structure proper design and sizing procedures, identify the factors which affect the performances and component sizing for PV system to optimize and utilize the energy production before any actual implementation of solar power energy system installed.

This paper proposed a single-phase single-stage high DC voltage multiplier converter. The conversion of high DC voltage converter without a DC-link is involved. A high frequency transformer using ETD 59 ferrite core with ratio 1:1 is used as energy storage and also providing isolation. Cockcroft-Walton circuit is connected at secondary side of the transformer. AC input is controlled by IGBT switch which the current flow in both directions of the transformer to fully utilize the transformer core. The current flow is controlled by the IGBTs using PWM technique. Experimental and simulation results are provided to show the effectives of the proposed technique

A new method of controlling high DC voltage based on Cockcroft Walton voltage multiplier circuit by using digital controller is presented. The digital controller is developed using complex programmable logic devices (CPLD). The proposed system utilizes a single-phase AC as an input supply. The power switching devices in the controlled bridge are controlled by the multiple-pulse pulse width modulation (PWM) switching technique so as to minimize the low order harmonic present on the AC side of the converter system. A low pass filter is incorporated in the circuit to filter out unwanted harmonics and to give a sinusoidal AC current. A high frequency transformer with 1:1 ratio is incorporated in the design to provide galvanic isolation for better circuit performance and protection. The optimum operation of transformer core in four quadrant of B-H curve is also considered in the proposed converter topology. The laboratory model of the converter is developed and tested. The experimental result is compared with the simulation result.

A mathematical approach of modelling and analysing three-phase pulse width modulation (PWM) is presented. The three-phase flyback converter required a unique pattern of PWM to optimise the power transfer in the magnetic circuit used in the converter. The three-phase PWM is generated digitally based on uniform symmetrical sampling technique using Xilinx chip. The generated PWM pattern is able to reduce the magnitude of the low order of harmonic components present in the input AC supply. Although software simulation could simulate the PWM pattern, it does not represent the exact pattern as been generated digitally. The mathematical approach used is to model the PWM pattern exactly as been created digitally. The proposed mathematical technique could also be used to analyse any digital PWM. The result of the mathematical analysis on the PWM pattern could be used to study the characteristics of the pattern such as maximum and minimum value of duty cycle, pulse width, turn-on time, turn-off time and modulation index. To verify the validity of the proposed technique, the results obtained from the mathematical model, experimental and simulation using PSpice were compared

This paper describes the application of a new simple voltage-boosting feature to a split-supply SR (switched-reluctance) motor inverter. As its name implies, the SR motor always operates in switching mode and has distinct motoring and generating rotor angular regions. The effectiveness of the energy conversion process of the SR motor depends basically on the ability of its inverter to inject adequate current during the positive-torque angular region and to reduce the current to a negligible value during the negative-torque angular region. The modified inverter effectively generates boost voltages for accelerating current build-up and decay and hence enhances the performance of SR motor drives. Benefits of the added boosting include: higher average current; better energy recovery during commutation; and a wider feasible speed range. This paper assesses the implications of the boost feature on inverter cost and performance. A time-stepping simulation procedure which includes the modelling of current overlapping between phases is presented together with simulation results.