Abstract

This paper presents an advanced Open Circuit Voltage (OCV) prediction technique for battery cells. The work contains an investigation to examine the relaxation voltage curves, to analyse the potential for the OCV prediction technique in a practical system. The technique described in this paper employs one simple equation to predict the equilibrated cell voltage after a small rest period. The practical work detailed in this paper was conducted at the Center for Automotive and Power System Engineering (CAPSE) battery laboratories at the University of South Wales (USW). The results indicate that the proposed OCV prediction technique is highly effective and using this technique appreciable benefit can be accrued.

Abstract

A Power System Stabilizer (PSS) installed in the excitation system of the synchronous generator improves the small-signal power system stability by damping out low frequency oscillations in the power system. This paper introduces the dynamic stability and analysis of a single machine connected to the infinite bus system (SMIB) with a power system stabilizer which is tuned with different controllers like fuzzy logic controller, PI and PID controllers which have been designed to provide a supplementary signal to the excitation system of the synchronous generator including the load damping parameter sensitivity. The simulations have been tested under different fault conditions and the obtained results show that the proposed controller for stabilizing power system can provide very good damping characteristics, compared to the conventional PSS and FPSS, through wide range of operating conditions for power system, and improves dynamic stability of the power system substantially. The responses for these different controller based PSS are compared. Matlab- Simulink is used to test the results.

Abstract

Now-a-days Renewable Energy Sources like Solar and Wind are becoming popular for household applications. Solar power is available in daytime only and there is no method of developing power for night loads except the use of power stored in batteries. Wind energy is the alternate energy available. A better solution for the above situation is the combination of PV and Wind to form a hybrid system for domestic loading. Integration of PV and Wind systems in the form of AC faces many difficulties such as synchronizing of phase, amplitude and frequency of the voltages. To avoid the complexities of integration in AC, this paper presents a simple way for integration in the DC form.

This paper presents a case study of JNT University Campus, where a fault is applied to JNTU network as a consideration of natural disaster. Under these conditions the power from Main Grid is turned off and the alternate power for desired loads is obtained from the PV-Wind hybrid system.

Abstract

A method proposed here for the placement of Distributed Generation (DG) in electrical distribution system in order to reduce the system power loss and voltage profile improvement. The DG real and reactive power injections typically installed near to the load centers and distribution system voltage support energy savings, and reliability improvement by reducing the losses in the system. This work focuses on the ancillary service of real power and also both real and reactive power support provided by DG. Artificial bee colony algorithm (ABC) is proposed to find the DG optimal size and location by using Loss Sensitivity Index (LSI) in order to minimize the total system real power loss. Simulation studies are examined on 33 and 69-bus radial test system to validate the proposed method with existing method.

Abstract

In this paper a method is proposed to detect voltage sag based on Empirical Mode Decomposition (EMD) with Hilbert Transform (called Hilbert-Huang Transform).The main characteristic feature of EMD is that it decomposes a nonstationary signal into mono component and symmetric signals called Intrinsic Mode Functions (IMFs). Further, the Hilbert transform is applied to each IMF to extract the features. The magnitude plot of the Hilbert Transform of one of the IMF correctly detects the event. Three voltage sag causes are taken in this paper (i) fault induced voltage sag, (ii) starting of induction motor and (iii) three phase transformer energization. Simulation/matlab results show the effectiveness of this method.

Abstract

Today energy is the most important basis for development of any country. Generation, transmission, distribution, and usage of energy are to be optimized for the proper conservation of energy. Electrical energy is generated from different sources like hydraulic power plants, thermal power plants, nuclear power plants etc. India has ample water sources to produce electrical energy. Presently the long time outage and fault detection during distribution are very serious problems. Also accidents are not uncommon in electrical transmission systems. It is too late to implement advanced systems for power distribution systems, if not implemented now. The main focus of the present work is to modernize the present systems with powerful tools like PLC and SCADA for automatic control of distribution systems. The automatic tap changer maintains the voltage of whole system normally. Thus much manpower could be reduced and major outages can be avoided with maximum safety of the system.