Exploring the dynamics of cash waqf: a critical analysis of its implementation in Malaysia

This paper explores the dynamics of the waqf institution in Islam, with special focus on cash waqf and its implementation in Malaysia. Its combined flexibility and accuracy is important to the real purpose of the waqf in its implementation. Its dynamics are first explored through its meaning and objectives as well as special features of waqf and cash waqf with special focus on the status of the endowed asset (mawqūf). The second part focuses on the critical evaluation of the current cash waqf practices in Malaysia. It is found that the special attention on the endowed asset ought to be maintained in order to preserve its original purpose. Waqf offers all kinds of assistance and is not confined to crisis management. Possessing the highest liquidity rate, cash waqf constitutes an important financial mechanism, especially given the current state of economic affairs. Its nature must be maintained, as suggested by those jurists who allow cash to be considered as an endowed asset (mawqūf) and also those who do not favour it, in order to maintain the perpetuity of the benefit. Only by adhering to this special arrangement, the real spirit of waqf and its dynamics can be preserved and further developed in order to fulfil the economic needs of society

A Simple Checking Algorithm with Perturb and Observe Maximum Power Point Tracking for Partially Shaded Photovoltaic System

This paper presents a simple checking algorithm for maximum power point tracking (MPPT) technique for Photovoltaic (PV) system using Perturb and Observe (P&O) algorithm. The main benefit of this checking algorithm is the simplicity and efficiency of the system whose duty cycle produced by the MPPT is smoother and changes faster according to maximum power point (MPP). This checking algorithm can determine the maximum power first before the P&O algorithm takes place to identify the voltage at MPP (VMPP), which is needed to calculate the duty cycle for the boost converter. To test the effectiveness of the algorithm, a simulation model of PV system has been carried out using MATLAB/Simulink under different level of irradiation; or in other words partially shaded condition of PV array. The results from the system using the proposed approach prove to have faster response and low ripple. Besides, the results are close to the desired outputs and exhibit an approximately 98.25% of the system efficiency. On the other hand, the system with conventional P&O MPPT seems to be unstable and has higher percentage of error. In summary, the proposed method is useful under varying level of irradiation with higher efficiency of the system

A Review on Perturb and Observe Maximum Power Point Tracking in Photovoltaic System

Solar energy is becoming popular and has drawn lots of attention from researchers nowadays. However, the output power of the photovoltaic (PV) arrays varies with solar irradiation and temperature, which affect the efficiency of PV arrays. Therefore, Maximum Power Point Tracking (MPPT) control technique is used to extract the maximum available power from the PV arrays. Perturb and Observe (P&O) algorithm is one of the favorite techniques frequently used due to its simplicity and low cost. Yet, the conventional P&O algorithm has several drawbacks, which leads to power loss and lack of efficiency. This paper presents comparison of the basic P&O algorithm with the modified P&O algorithm used for partial shading condition in terms of complexity, accuracy, cost, and basic concept of each method

Extended family of DC-DC Quasi-Z-Source converters

The family of DC-DC q-ZSCs is extended from two to three classes and four to six members. All the members were analyzed based on efficient duty ratio range (RDeff) and general duty ratio range (RDgen). Findings showed that similar to the traditional buck-boost converter (BBC), each of the topologies is theoretically capable of inverted buck-boost (BB) operation for the RDgen with additional advantages but differed according to class in how the gains are achieved. The new topologies have advantages of BB capability at the RDeff, continuous and operable duty ratio range with unity gain at  contrary to existing topologies where undefined or zero gain is produced. Potential applications of each class were discussed with suitable topologies for applications such as fuel cells, photovoltaic, uninterruptible power supply (UPS), hybrid energy storage and load levelling systems identified

A Study of Shading Effect on Photovoltaic Modules with Proposed P&O Checking Algorithm

Sun irradiation levels and associated temperature changes are the main factors that influence the conversion of solar energy into electricity. Most energy is produced during a hot sunny day as the sun irradiation is at the maximum level and uniform throughout the solar photovoltaic (PV). However, most solar PV were frequently get shadowed, completely or partially, by the neighbouring buildings, trees and passing clouds. Consequently, the solar PV has lower voltage and current output; hence, multiple maximum power points (MPP) are existed on the PV curve, which could cause confusion to the conventional Maximum Power Point Tracker (MPPT) to track the true MPP for the PV system. Thus, it is important to examine the impacts of partial shading on the solar PV in order to extract the maximum possible power. This paper presents a MATLAB-based modelling for simulation and experimental setup to study the I-V and P-V characteristics of a solar module under a non-uniform irradiation due to partial shading condition (PSC).  Furthermore, this study is also proposed an effective method (a variable step size of P&O with checking algorithm) that is low cost and higher tracking efficiency. Thus, this study is essential in improving and evaluating any new MPPT algorithm under the PSC

Asymmetric quasi impedance source buck-boost converter

An impedance source buck-boost converter (BBC) prototype for renewable energy (RE) application in the transportation industry is proposed. Its functions include stabilizing the variable output voltage of the RE sources such as fuel cells and photovoltaic cells. The converter utilized a topology of DC-DC quasi-impedance source converters (q-ZSCs) to achieve the gain curve of the BBC. With BBC gain curve, the converter earned advantages over the two other classes of non-isolated DC-DC q-ZSCs. These advantages include ecient buck-boost capability at the ecient duty ratio range of 0:35-0:65 and continuous and non-zero gain at the ecient duty ratio range. The converter's q-ZSC topology implies using two capacitors and two inductors. These two capacitors and inductors formed two separate LC filters that provides second order filtering compared to the first order filtering in BBC. Its other advantages over the traditional BBC include elim-ination of dead and overlap-time, simple contol and permitting higher switching frequency operation. The converter is capable of utilizing high switching frequency and asymmetric components to achieve BBC gain by using smaller components to reduce cost, weight and size. Its simulation response and that of a correspond-ing BBC for some given specifications were compared, presented and analyzed. An experimental scaled-down prototype was also developed to confirm its operation. Analysis of the converters responses comfirmed the prototype's second order filtering as against the first order filtering in traditional BBC

Substitution of waqf in Terengganu: maqasid shariah and public interest approach

Abstract. Application of waqf property in modern society is highly anticipated to fulfill more demand for economic growth and development and help the needs in society. Therefore, Istibdal Waqf is indispensable in the implementation of waqf so the waqf property will not be wasted and always beneficial to society. Although the Istibdal Waqf is important but it is doubtful whether it is a necessity (Daruriyyat) for the society or needs (Hajiyyat) or embellishment (Tahsiniyyat) while the discussion are involve in the framework of Maqasid Shariah so the main purpose of waqf are still preserved. This article aims at discussing the issues with regard to the application of Istibdal Waqf concept in Islam. Specifically, the study sets out to explain on the importance of Istibdal Waqf for muslim society in the framework of maqasid shariah and public interest. The study also focusing on Istibdal inTerengganu as case stud

A Review on Favourable Maximum Power Point Tracking Systems in Solar Energy Application

This paper reviews different types of maximum power point tracking (MPPT) techniques for solar photovoltaic (PV) application. Since the PV output power is known affected by sun radiation and temperature, it is necessary to search for an effective method for extracting maximum amount of power from PV cell/modules. In this study, a total of seven control algorithms were selected, comprising the most popular methods among the established techniques. A comparison in terms of convergence speed, complexity, as well as the basic concept of each method had been carried out for future reference. Based on the accessible simulation results, modified Perturb and Observe (P&O) method had shown its effectiveness for obtaining actual maximum power point while solving major drawbacks of the conventional P&O. This paper also discusses typical solar MPPT system, including the pros and cons of each part of the system

Dynamic model of A DC-DC quasi-Z-source converter (q-ZSC)

Two quasi-Z-source DC-DC converters (q-ZSCs) with buck-boost converter gain were recently proposed. The converters have advantages of continuous gain curve, higher gain magnitude and buck-boost operation at efficient duty ratio range when compared with existing q-ZSCs. Accurate dynamic models of these converters are needed for global and detailed overview by understanding their operation limits and effects of components sizes. A dynamic model of one of these converters is proposed here by first deriving the gain equation, state equations and state space model. A generalized small signal model was also derived before localizing it to this topology. The transfer functions (TF) were all derived, the poles and zeros analyzed with the boundaries for stable operations presented and discussed. Some of the findings include existence of right-hand plane (RHP) zero in the duty ratio to output capacitor voltage TF. This is common to the Z-source and quasi-Z-source topologies and implies control limitations. Parasitic resistances of the capacitors and inductors affect the nature and positions of the poles and zeros. It was also found and verified that rather than symmetric components, use of carefully selected smaller asymmetric components L1 and C1 produces less parasitic voltage drop, higher output voltage and current under the same conditions, thus better efficiency and performance at reduced cost, size and weight

DC bus stabilization using passive damping network in distributed power system with constant power load

In distributed power system (DPS), the stability performance is always associated with the behaviour of constant power load (CPL). Since DPS large complex system build up from many power electronic converters, the DC bus of the system becomes unstable due to the strenuous action from power converters. When these converters tightly regulated, it behaves as constant power load and exhibit negative incremental input impedance which becomes the main reason in stability degradation of DPS. In this paper, four passive damping network topologies was proposed to reduce the DC bus instability. The best damping performance of the topologies was chosen and analysed using MATLAB/Simulink. The DC bus performances was studied in four cases which are damping behavior due to CPL power level, CPL disconnection, effects of filter and damping capacitor, and effects of filter cut-off frequency. Simulation results obtained shows that the DC bus was successfully stabilized and the resonance damped when passive damper installed. An experimental hardware tests was conducted to verify the proposed damping method and the results were compared with the simulated output waveforms. The analysis results in overshoot, settling time and steady state error of bus voltage shows system improvement with the proposed damper network