Ankur Singh Rana

A modified algorithm for time varying reactive power control and harmonics compensation by D-STATCOM

This paper presents a modified id-iq based control algorithm for time varying active and reactive power control and load harmonics compensation by DSTATCOM under load fluctuations. The proposed scheme of control algorithm has been introduced for enhancing steady-state performances in addition to useful elimination of power quality disturbances. Employing a preexisting D-STATCOM to attain these added control purposes can advantage system handling operators to maximize complete response of the system. For regulating the time varying active and reactive power control, an extra current control loop system is provided and consequently comprised in the control block. To validate its application, a 200-V electricity feeder with a 3-phase rectifier as a non-linear load was simulated. Results obtained proved that addition of an extra control loop of current component of reactive power can regulate active as well as reactive power drawn on controlled feeder completely under the fluctuations of load.reactive power controltime varying active power controlload harmonics compensationload fluctuations.control algorithmsteady-state performancespower quality disturbances.

Analysis of time delay in a wide-area communication network

This paper describes communication infrastructure of wide area monitoring and control (WAMC) system. It also shows model for communication delay and explains its basic components. The present model uses fibre optics communication link for transmission of data. The delay is simulated for dedicated communication network with different channel capacity as well as for shared networks with and without background load. Communication delay has been calculated for WAMC network proposed for the Indian Power Sector. The result shows dependence of the WAMC network configuration, link capacity as well as the distance of PMUs and PDCs on the communication delay.

A pole-placement approach for buck converter based PV array Emulator

This paper presents the Photovoltaic (PV) array Emulator based on DC-DC buck converter control by the pole placement technique. A photovoltaic array emulator has the similar electrical characteristics to a photovoltaic panel or module. The photovoltaic array emulator independent from the environment condition so it generate and maintain same characteristics of real photovoltaic system. Here pole placement technique is used to control photovoltaic emulators voltage and current characteristics which obtain by PV model. This whole system has been evaluated in MATLAB with linear and nonlinear loads. The simulation results shows that the PV array emulator gives similar behavior like real PV system.

Wide Area Measurement system performance based on latency and link utilization

Wide Area Measurement system (WAMS) is best equipped to handle the dynamics of power system. WAMS performance is the function of its communication infrastructure. Communication infrastructures performance is defined in terms of latency and utilization of links. This paper describes a communication model of WAMS designed in OPNET which uses fictitious PMUs installed at different locations. Latency and link utilization parameters of communication have been studied and their values are obtained for the aforesaid model. Further, Latency components have been comprehensively described in the paper and delay equation has been obtained. The relation between latency and link utilization is also evaluated in this paper.

Exploring IEEE standard for synchrophasor C37.118 with practical implementation

Measurement of precise synchronized voltage and current values are paramount in power system. Through synchronisation it is possible to locate phasors, taken at different locations, on same phasor diagram. It is helpful in analyzing, monitoring and controlling the power systems during dynamic and transient state. PMU (Phasor Measurement Unit) is a gold standard device, synchronized with highly accurate GPS clock, used to measure synchrophasors. The latest revised version of standard for synchrophasor measurements and synchrophasor data transfer for power systems are described in IEEE standard C37.118.1 [1] and C37.118.2 [2] respectively approved by IEEE-SA standards board on 7 Dec 2011. The purpose of this paper to promulgate and endorse the availability of the latest revised IEEE standard for synchrophasor to the society of power engineering. The paper also shows the laboratory set-up based on the standard C37.118 for measurement and data transfer in power system.

Power Systems Reliability- A Bibliographical Survey

Abstract With deregulation of electricity sector, maintenance and reliability of power system network has become a major challenging task for an independent system operator. The power supply reliability influences customer satisfaction and hence choice of suppliers. There is a growing interest in investigation and development of new tools, methods, and models for evaluating reliability of power system network. This paper provides a bibliographical survey of current state of development, research and applicable tools in evaluation of power system reliability.

A practical approach for locating faults for overhead transmission lines using synchronized measurements from PMUs

A synchophasor based scheme for locating faults on transmission lines is presented in this paper. The synchronized measurements are obtained from phasor measurement unit (PMU). The phasors of voltage and current at the two line terminals are acquired using PMUs installed at the two terminals. The impedance of the system at the time of fault is solved using suddenly changed positive sequence components of voltage and current those are obtained from the suddenly changed phasors of current and voltage. This system impedance is utilized in the calculation of the distance to fault. The proposed algorithm is applied to an 115kV system. Results revealed that the proposed scheme precisely locate the fault distance and is not affected by fault type and resistance.

Communication latency reduction in wide area measurement control and protection system

Abstract Latency in communication network is critical in wide area measurement control and protection (WAMCP) of large power networks, as it deteriorates the system performance. In this paper, the WAMCP communication network is analysed in the context of data latency for dedicated as well as shared topologies. In an attempt to increase the overall reliability of the WAMCP, new communication architecture is proposed. Also, different methods are discussed to reduce the latency values of WAMCP. In case of shared networks, two routing protocols have been compared—distance vector and link state routing protocols—for different scenarios in terms of link failures. The role of the phasor data concentrator (PDC) timeout settings in reducing the communication delay is also presented.

An improved SRF based control algorithm for D-STATCOM under abnormal source voltage

This paper describes an improved SRF (Synchronous Reference Frame) based control technique or algorithm for time varying power flow control and optimum load compensation of non-linear loading under abnormal or disturbed source voltage by D-STATCOM designed for three-phase three wire systems. The improved algorithm is based on the active power separation and imaginary symmetrical components of voltage and has been compared with conventional IRP based algorithm to show the preciseness in finding the reference current for a DSTATCOM under abnormal i.e. asymmetric and distorted source voltage. Individually the algorithms were implemented and simulated under MATLAB/Simulink. The simulation results also show which algorithm can accurately detect the harmonics and reactive component of load current even under the asymmetric and distorted source voltage condition. Additionally by the control loop of reactive power of improved algorithm, load reactive power can be compensated as well as regulated under variations of load. Thus this additional control arrangement can help system operators improve overall system performances.

Improving the performance and reliability of IEC 61850 based substation using backup IED concept

Intelligent Electronic Devices (IEDs) are being used extensively in Substation Automation Systems and the concept of back up IEDs is of significance. In this paper the performance and reliability of IEC 61850 based substation, is assessed by simulation and verified by experimental approach. Modification of an actual IEC 61850 based substation is done and a new backup IED concept is introduced to reduce the number of IEDs used in the substation and at the same time improving the reliability of substation. Equipment from different vendors are used to configure the substation to configure the substation with a new backup IED concept.