Design of FNN AVR for Enhancement of Power System Stability Using Matlab/Simulink

A simple technique of excitation voltage control with NNAVR (Neural Network Automatic Voltage Regulator) is proposed in this paper. Popular type of ANN (Artificial Neural Networks) known as RBF (Radial Basis Function) architectures with OLS (Orthogonal Least Square) algorithm is suggested to design AVR in order to prove its applicability and suitability. This proposed technique is implemented considering as SMIB (Single Machine Connected to Infinite Bus) system with linearized model of synchronous machine and its excitation system using Matlab/Simulink. The simulation results of RBF AVR, when compared with conventional AVR controllers show better performance, improve the transient and small signal stability of the system and above all its response is more suitable in case of load changing conditions

POLITICAL BEHAVIOUR IN PAKISTAN

Pakistan gained its independence from direct colonial rule with much hope for the betterment of its largely Muslim population of peasants and labourers, which has remained unrealized to this day, not only economically but educationally and politically. Analysts blame the failures in these important areas on the illiteracy and ignorance of the masses, lack of preparedness in democracy, immature political behaviour in their every day political affairs, decreasing level of interests in national politics and continued political instability from its independence to date

Wavelet Transform and ANNs for Detection and Classification of Power Signal Disturbances

This article proposes WT (Wavelet Transform) and an ANN (Artificial Neural Network) based approach for detection and classification of EPQDs (Electrical Power Quality Disturbances). A modified WT known as ST (Stockwell Transform) is suggested for feature extraction and PNN (Probabilistic Neural Network) for pattern classification. The ST possesses outstanding time-frequency resolution characteristics and its phase correction techniques determine the phase of the WT to the zero time point. The feature vectors for the input of PNN are extracted using ST technique and these obtained features are discrete, logical, and unaffected to noisy data of distorted signals. The data of the models required to develop the distorted EPQ (Electrical Power Quality) signals, is obtained within the ranges specified by IEEE 1159-1995 in its literatures. The features vectors including noisy time varying data during steady state or transient condition and extracted using the ST, are trained through PNN for pattern classification. Their simulation results demonstrate that the proposed methodology is successful and can classify EPQD

Combined Approach of PNN and Time-Frequency as the Classifier for Power System Transient Problems

The transients in power system cause serious disturbances in the reliability, safety and economy of the system. The transient signals possess the nonstationary characteristics in which the frequency as well as varying time information is compulsory for the analysis. Hence, it is vital, first to detect and classify the type of transient fault and then to mitigate them. This article proposes time-frequency and FFNN (Feedforward Neural Network) approach for the classification of power system transients problems. In this work it is suggested that all the major categories of transients are simulated, de-noised, and decomposed with DWT (Discrete Wavelet) and MRA (Multiresolution Analysis) algorithm and then distinctive features are extracted to get optimal vector as input for training of PNN (Probabilistic Neural Network) classifier. The simulation results of proposed approach prove their simplicity, accurateness and effectiveness for the automatic detection and classification of PST (Power System Transient) type

Political Instability: A case study of Pakistan

Political instability has become a serious and threatening problem especially in developing and underdeveloped countries. It is creating massive problems and hindering the development of these countries. The theme of this article revolves around the problem of political stability in context of identity and legitimacy crisis in Pakistan. Political stability plays an important role in keeping society integrated and in maintaining legitimacy within the state. It is a prerequisite for the economic development, social integration, and supremacy of law in a state. The stability of political system has direct effects on the processes of nation and state building. These both require stable political systems for their growth and flourishing. The development of nation and state without firm and organized system of politics is not possible and government becomes only a tug of war amongst various interest groups. In sum, article endeavors to explore thepossible causes and effects of political instability in Pakistan

POLE PLACEMENT DESIGN FOR LOAD FREQUENCY CONTROL (LFC) OF AN ISOLATED POWER SYSTEM

The classical design techniques are based on the root-locus that utilize only the plant output for feedback with a dynamic controller, in this paper, we employ modern control designs that require the use of all state variables to form a linear static controller. Modern control design is especially useful in multivariable systems. One approach in modern control system accomplished by the use of state feedback is known as Pole-Placement Design. The pole-placement design allows all roots of the system characteristic equation to be placed in desired locations. This result in a regulator with constant gain vector K. The state-variable feedback concept requires that all states be accessible in a physical system. For systems in which all states are not available for feedback, a state estimator (observer) may be designed to implement the pole-placement design

The performance prediction and techno-economic analyses of a stand-alone parabolic solar dish/stirling system, for Jamshoro, Pakistan

This study aims to propose a simulation as well as mathematical model to carry out the performance assessment and efficiency improvement of a stand-alone Parabolic Solar Dish Stirling (PSDS) system. The simulation for a 25 ​kW PSDS system is performed in the System Advisor Model (SAM) under the environmental conditions of Jamshoro, Sindh, Pakistan. The results show that the city has a good potential of direct solar irradiance with yearly average value of 1719.15 ​kWh/m2/y. The system can generate yearly 38.6 ​MWh with overall system net efficiency of 23.39%. Whereas, the maximum energy of 3.38 ​MWh is produced in month of January, due to high solar irradiance. However, the lowest energy of 2.15 ​MWh is produced in July, due to the monsoon spell in selected city. Furthermore, from the techno-economic analyses of the proposed system, the levelized cost of energy is found to be 0.13 $/kWh, which is quite low. As the Stirling Engine (SE) works at higher temperature, so, increasing the diameter of concentrator results more thermal energy at the cavity. The solar radiations are high around the solar noon, therefore, the operating temperature can damage the hot-side of SE due to thermal overloading. In future, to protect the hot-side of SE, it is recommended to use thermo electric generator