List of Titles

Verification of latency and delays related to a digital topology based on IEC 61850

- Kumar, Shantanu, Das, Narottam, Islam, Syed, Abu-Siada, Ahmed

Authors: Kumar, Shantanu , Das, Narottam , Islam, Syed , Abu-Siada, Ahmed
Date: 2019
Type: Text , Conference proceedings , Conference paper
Relation: 2019 29th Australasian Universities Power Engineering Conference (AUPEC2019); Momi Bay, Fiji; 26th-29th November 2019
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Description: Digital Communication systems have matured to a point of acceptance in the last decade enormously based on IEC 61850 guidelines from Substation Automation System (SAS) perspective. However, these networks have issues related to latency, data clogging delays, errors etc. in the digital protection system. Measuring propagation delays and assessing the performance of IED's and other peripherals in an Ethernet topology play a critical role in relay coordination setting. This paper discusses issues associated with a digital network and addresses the problems that could mitigate spurious tripping or compromise the protection of the assets in the feeders leading to a reliable operation of the protection system. The discussion in this paper is carried out based on a case study related to a digital star topology using Optimized Network Engineering Tool (OPNET) software of a 132/22-kV zone substation. We report the practical case of measuring delay time during frame exchanges of Generic Object Oriented Substation Event (GOOSE) and Sampled Value (SV) messages amongst the IED' and peripherals.

Detection of power transformer winding deformation using improved FRA based on binary morphology and extreme point variation

- Zhao, Zhongyong, Yao, Chenguo, Li, Chengxiang, Islam, Syed

Authors: Zhao, Zhongyong , Yao, Chenguo , Li, Chengxiang , Islam, Syed
Date: 2018
Type: Text , Journal article
Relation: IEEE Transactions on Industrial Electronics Vol. 65, no. 4 (2018), p. 3509-3519
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Description: IEEE Frequency response analysis (FRA) has recently been developed as a widely accepted tool for power transformer winding mechanical deformation diagnosis, and has proven to be effective and powerful in many cases. However, there still exist problems regarding the application of FRA. FRA is a comparative method in which the measured FRA signature should be compared with its fingerprint. Small differences of FRA signatures in certain frequency bands might be produced by external disturbance, which hinders fault diagnosis. Additionally, the existing correlation coefficient indicator recommended by power industry standards cannot reflect key information of signatures, namely the extreme points. This paper proposes an improved FRA based on binary morphology and extreme point variation. Binary morphology is first introduced to extract the certain frequency bands of signatures with significant difference. A composite indicator of extreme point variation is adopted to realize the diagnosis of fault level. A ternary diagram is constructed by the area proportions of the binary image to identify winding faults, which has a potential to realize cluster analysis of fault types.

Electrical power engineering education down under : Australia and New Zealand are adding energy to their University Curricula

- Nair, Nirmal, Martin, Daniel, Saha, Tapan, Islam, Syed, Watson, Neville

Authors: Nair, Nirmal , Martin, Daniel , Saha, Tapan , Islam, Syed , Watson, Neville
Date: 2018
Type: Text , Journal article
Relation: IEEE Power and Energy Magazine Vol. 16, no. 5 (2018), p. 64-73
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Description: On 4 August 1888, Reefton became the first town in New Zealand to have its own public electricity supply powered by hydrogeneration. In Australia, the first supply of electricity to the public at large was in two small country towns in New South Wales. Tamworth, with a population of 3,000, switched on arc and incandescent street lighting on 9 November 1888. In April 1889, the smaller town of Young switched on its incandescent street lighting and shortly thereafter went on to connect shops, offices, and homes within reach of its lines. However, the history of electricity supply in Australia traces back earlier, with Brisbane as one of the first cities in Australia to use electricity commercially, in 1882. Thus, electricity utilization down under coincided with the history of its emergence among the countries of the Northern Hemisphere.

Experimental modeling of Nano power generation using thermoelectric generator (TEG) from incinerator waste heat

- Fauzan, Miftah, Islam, Syed, Muyeen, S, Wardhana, Asepta, Soedibyo, Ashari, Mochamad

Authors: Fauzan, Miftah , Islam, Syed , Muyeen, S , Wardhana, Asepta , Soedibyo , Ashari, Mochamad
Date: 2018
Type: Text , Conference proceedings
Relation: 2018 International Seminar on Intelligent Technology and Its Applications (ISITIA);Bali, Indonesia; 30-31 Aug, 2018 p. 67-70
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Description: This paper presents experimental investigation of nano power generation, less than 1 kW size, using Thermoelectric Generator (TEG). The heat source is expected from waste temperature of incinerator, but in the laboratory experimental it was from electric heat source controlled by electronics device. A prototype of 0.02 kW system, comprising 24 modules of TEG bismuth telluride type connected in series, was built. The system is attached with cooling and temperature control to investigate the characteristics. Preliminary experiments and analytical models of electric output power as function of specific temperature were presented. An optimum output power could be set at a certain condition.

High voltage substation automation and protection system based on IEC 61850

- Kumar, Shantanu, Das, Narottam, Islam, Syed

Authors: Kumar, Shantanu , Das, Narottam , Islam, Syed
Date: 2018
Type: Text , Conference proceedings
Relation: 2018 Australasian Universities Power Engineering Conference (AUPEC);Auckland, New Zealand; 27-30 Nov. 2018
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Description: Digital Communication is the future of High Voltage (HV) substation automation, protection and control. It not only offer ease of diagnostics but acts fast to isolate healthy feeders from faulty ones. The effect of this digital protection technology is being appreciated by many utilities and industries for the benefit it offers to them and looks to be the future. Some of the utilities are replacing their secondary copper wires with Fibre Optics (FO) and Ethernet wires as they want load the cable trays less and identify the FO better than the secondary copper wires. Conventional relays are being replaced with Intelligent Electronic Devices (IEDs) during asset management replacement program. Switchyard equipment such as instrument transformers filled with oil and SF6 gas are being replaced with Non-Conventional Instrument Transformer (NCITs). Ushering new devices into the network are not without challenges. These devices and peripherals cannot be put into use by the end user without proper assessment and needs to be validated with number of tests for its performances. To get end users acceptance, laboratory and field tests are carried out to study the propagation delays and performance issues as applicable to digital automation and protection scheme. This paper discusses an early detection of the loss of data packets in a star connected Ethernet Substation Automation Systems (SAS). Understanding a real model in a lab environment is an important step towards performance evaluation and identification of issues. With the involvement of multiple manufacturer in the digital substation, it is good to set a trial of the interoperability of equipment involving their products which could address critical protection issues. This paper focuses on a star connected architecture using an Optimized Network Engineering Tool (OPNET) lab-based software simulating the latency and delays of a digital protection scheme in a 132/22-kV zone substation.

Implementing PRP and HSR Schemes in a HV Substation based on IEC62439-3

- Kumar, Shantanu, Das, Narottam, Islam, Syed

Authors: Kumar, Shantanu , Das, Narottam , Islam, Syed
Date: 2018
Type: Text , Conference proceedings
Relation: 2018 Condition Monitoring and Diagnosis (CMD); Perth, WA, Australia; 23-26 Sept. 2018 p. 1-5
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Description: High speed communication is an essential feature of Substation Automation and Control. Existing International Electro-technical Commission (IEC) 61850 guidelines substation automation and communication systems have few shortcomings in the protection architecture which necessitated an upgrade to another guideline. This has been addressed better in IEC 62439-3 standard encompassing Parallel Redundancy Protocol (PRP) and High-availability Seamless Redundancy (HSR), Earlier there have been number of issues with IEC 61850, due to single port failure, data losses and interoperability related to multi-vendor equipment. The enhanced features of a Double Attached Node component based on IEC 62439-3, provide redundancy in protection by virtue of having two active frames circulating in the ring. These frames send out copies in the ring. Should one of them be lost, the destination node will receive alternate frame, ensuring flawless data transfer at a significant faster speed in a multi-vendor equipment ensuring the circuit is fault resilient. PRP and HSR topologies promise enhanced reliability over IEC 61850 standard due to faster processing capabilities, increased availability in the scheme with least delay time in circulating data packet in wireless communication in the network. This paper exhibit performance of PRP and HSR topologies addressing redundancy within the network ring leveraging on IEC 62439-3.

Performance evaluation of two interconnected high voltage utility substations using PRP topology based on IEC 62439-3

- Kumar, Shantanu, Das, Narottam, Islam, Syed

Authors: Kumar, Shantanu , Das, Narottam , Islam, Syed
Date: 2018
Type: Text , Conference proceedings
Relation: 2017 Australasian Universities Power Engineering Conference, AUPEC 2017; Melbourne, Australia; 19th-22nd November 2017 Vol. 2017, p. 1-5
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Description: In a modern power system network having multiple interconnected High Voltage (HV) substations, communication amongst Intelligent Electronic Devices (IED) becomes an important feature in an automation system. Time critical information, such as feeder faults, overcurrent, under frequency messages between multiple geographically isolated substations have opened up number of issues related to reliability in protection, automation and control. There are problems related to latency, data loss and transfer of Sampled Value (SV) packets transmitted to these inter-connected substations on radio wireless and Ethernet mode linked up in a Wide Area Network (WAN) configuration. Few other key area of concerns in a digital protection scheme are packet losses, errors in packet arrival at destination, latency in transmission, End to End delay in packet transfer due to flooding of the network, out of sequence packet arrival etc. Error prone packets could seriously compromise the protection scheme and endanger the safety of primary plant assets in a transmission substation. This paper investigates performance of SV packet transmission between two interconnected substations]. Practical simulations were performed to evaluate the performance of SV packets in a laboratory set up to assess the performance of digital protection scheme based on Parallel Redundancy Protocol (PRP) topology involving digital equipment such as Merger Units (MUs), switches, IEDs and Redundant boxes (Red box), etc.

Time-delay analysis of wide area voltage control considering smart grid contingences in real-time environment

- Musleh, Ahmed, Muyeen, S., Al-Durra, Ahmed, Kamwa, Innocent, Masoum, Mohammad, Islam, Syed

Authors: Musleh, Ahmed , Muyeen, S. , Al-Durra, Ahmed , Kamwa, Innocent , Masoum, Mohammad , Islam, Syed
Date: 2018
Type: Text , Journal article
Relation: IEEE Transactions on Industrial Informatics Vol. 14, no. 3 (2018), p. 1242-1252
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Description: IEEE This paper addresses the time delay effects of the wide area monitoring and control systems (WAMCS) in smart power grids which may critically impact system stability. The main purpose is to conduct a detailed delay analysis of the WAMCS in case of grid contingences. This analysis is performed via an advanced WAMCS testbed where a wide area controller (WAC) for a flexible AC transmission system (FACTS) device is implemented. The real-time measurements for the WAC are collected using phasor measurements units (PMU). The testbed is resulted from an interface of four main segments known as the WAC, the actual FACTS device, the local area controller, and the power grid system along with the PMUs are simulated via real time digital simulator (RTDS). To mimic the real case scenario both hardware-in-the-loop (HIL) and software-in-the-loop (SIL) schemes are adopted in the experimental testbed, considering time delay effects. The results obtained clarify the effect of delay in WAMCS in case of smart grid contingences.

A novel generalized concept for three phase cascaded multilevel inverter topologies

- Hasan,Md Mubashwar, Abu-Siada, Ahmed, Islam, Syed, Muyeen, S

Authors: Hasan,Md Mubashwar , Abu-Siada, Ahmed , Islam, Syed , Muyeen, S
Date: 2017
Type: Text , Conference proceedings
Relation: 9th Annual IEEE Green Technologies Conference (GreenTech 2017); Denver, CO; 29th-21st March, 2017 p. 110-117
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Description: Many new cascaded multilevel inverter (MLI) topologies have recently been proposed and published in the literature. All proposed topologies demand significant amount of semiconductor components and input dc supplies, which is considered the main drawback for the implementation of three phase cascaded MLIs. This paper proposes a new generalized concept that could be employed within any existing cascaded MLI topology in order to reduce its size in terms of device count including semiconductor switches, diodes, and dc power supplies. The new generalized concept involves two stages namely, cascaded stage (CS) and phase generator stage (PGS). The PGS stage is a combination of conventional three phase two level inverter (CTPTLI) and three bidirectional (BD) switches, while the cascaded stage can be modified using any existing cascaded topology. The proposed concept is validated through extensive simulation and experimental analyses. Results show the capability of the proposed technique in reducing device count of the existing topologies while maintaining its performance.

A three-phase half-bridge cascaded inverter with reduced number of input DC supply

- Hasan, Mubashwar, Abu-Siada, Ahmed, Islam, Syed, Muyeen, S.

Authors: Hasan, Mubashwar , Abu-Siada, Ahmed , Islam, Syed , Muyeen, S.
Date: 2017
Type: Text , Conference proceedings
Relation: 2017 Australasian Universities Power Engineering Conference, AUPEC 2017; Melbourne, Australia; 19th-22nd November 2017 Vol. 2017, p. 1-7
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Description: Cascaded multilevel inverters (MLI) have recently received much attention due to its ability to perform well in various high voltage and high power applications with high efficiency. Cascaded inverters are able to generate high voltage output by utilizing a number of low voltage DC supplies and switches of low blocking voltage rating, which make cascaded MLI a cost effective choice for high voltage/power applications. The main drawback of cascaded MLI is the requirement of large number of isolated DC sources particularly, for three phase applications where the number of required input DC sources is three times that of single phase structure. In addition to the extra cost it will incur, the use of large number of DC supplies within the inverter will significantly increase its physical size, and complicate the management of such large number of DC sources. This paper presents a new topology for three phase MLI with a minimum number of input DC supplies. Symmetric and asymmetric input DC supply modes are developed for the proposed topology. Simulation and experimental results are provided to assess the performance of the proposed MLI topology.

An experimental thermographic safety audit focusing on temperature rise vs load in electrical installations in a Bangladesh garments factory

- Islam, Syed, Huque, Mozammel, Khan, Liakot, Hossain, Imran

Authors: Islam, Syed , Huque, Mozammel , Khan, Liakot , Hossain, Imran
Date: 2017
Type: Text , Conference proceedings , Conference paper
Relation: 4th International Conference on Advances in Electrical Engineering, ICAEE 2017; Dhaka, Bangladesh; 28th-30th September 2017 Vol. 2018, p. 561-564
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Description: Thermographic scanning of electrical installations is sometimes conducted as part of electrical safety audits. This scanning is mostly considered based on the present temperature identified on a particular device or location and according to a pre-specified temperature category. But in most of the cases the recommended temperature of the particular devices cannot be considered during temperature categorization. There are many electrical audits using Thermographic scanning and recommend solution based on normal category of temperature rather than manufacturer's suggestion or specified standard for particular electrical device. Now a days, thermographic scanning is being used in Readymade Garments (RMG) industries in Bangladesh in such simple way where details analysis are not in practice and hence exact recommendation is absent in reports. The importance of this topic is focused on the 4.2 million people working in more than 5,000 factories in Bangladesh, where 80% of the fire incident are caused by inappropriate electrical installation or short circuits (as per Fire Service and Civil Defense statistics of Bangladesh). Recently many violent industrial accidents caused death of more than 1,500 people in the last 3 years. Among these, majority of the incidents were due to unsafe electrical system and inappropriate maintenance. The paper will further explore the importance of thermal scanning on electrical devices and compare the temperature considering manufacturer's recommendation for identifying system errors. The paper is written based on previously published recommendations and based on conducting an experimental sample audit aimed to develop a thermography based auditing standard. Based on the statistical and systematic analysis of the obtained data (e.g. temperature values, visual abnormalities, comparative differences) the paper will further discuss the possible area(s) that can be improved by introducing the thermal reports for the safety audits. This paper is aimed to develop an auditing structure proposed to implement identified areas within a standard electrical safety audit process.

Application of S transform for detection of external interferences in online transformer impulse frequency response analysis

- Mohseni, Bahar, Hashemnia, Naser, Islam, Syed

Authors: Mohseni, Bahar , Hashemnia, Naser , Islam, Syed
Date: 2017
Type: Text , Conference proceedings , Conference paper
Relation: 17th IEEE International Conference on Environment and Electrical Engineering and 2017 1st IEEE Industrial and Commercial Power Systems Europe, EEEIC / I and CPS Europe 2017; Milan, Italy; 6th-9th June 2017 p. 1-4
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Description: Online impulse frequency response analysis is a recently-developed diagnostic method for in service transformer with a promising outlook. This paper aims to detect the impact of external interferences including pulse shaped interferences from switching operations and other phenomena in the power system on the frequency response of the transformer. For modeling the transformer for online IFRA, a simulation approach based on finite element analysis (FEA) and circuit analysis is used. In this approach, instead of using a linear model with static parameters, 3D finite element model of the transformer is calculated in Maxwell Software and then exported into an external Maxwell Spice circuit which allows for study the terminal behaviors of the transformer. A modified S transform is then applied to the recorded input and output signals in healthy and faulty conditions to construct the electrical impedance as well as the time-frequency contours of the transient responses.

Battery impedance measurement using sinusoidal ripple current emulator

- Hossain, Kamal, Islam, Syed, Park, Sung-Yeul

Authors: Hossain, Kamal , Islam, Syed , Park, Sung-Yeul
Date: 2017
Type: Text , Conference proceedings , Conference paper
Relation: 9th Annual IEEE Energy Conversion Congress and Exposition, ECCE 2017; Cincinnati, United States; 1st-5th October 2017 Vol. 2017, p. 2754-2759
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Description: This paper presents a sinusoidal ripple current (SRC) emulator which superimposes an ac ripple current frequency into a dc charging current in order to produce a sinusoidal ripple current without a ripple current controller. It can be used for several purposes:1) to analyze the impact of ac ripple current magnitude and frequency on the battery internal characteristics; 2) to determine the parameters related to thermal rise and lithium plating; 3) to obtain more updated parameter information for improved utilization of a battery; 4) to determine the optimal ripple current frequency at the minimum impedance point by sweeping the ripple current frequency; 5) to utilize the obtained impedance data for estimating the battery circuit parameters and SOC level. The internal characteristics of batteries are complex and dynamic; therefore, it is beneficial to use the SRC emulator to validate SRC performance in a battery stack before integrating a SRC algorithm into a battery charger. This paper describes the development procedure of a SRC emulator to produce the electrochemical impedance spectroscopy (EIS) measurement for measuring the battery internal impedance. In order to validate the performance of the SRC emulator, a 12.8 V, 40 Ah Li-ion battery was charged at C/8 rate in CC mode with ± 1 App ac ripple current perturbation with an impedance from 20 Hz to 2 kHz.

Online detection of partial discharge inside power transformer winding through IFRA

- Mohseni, Bahar, Hashemnia, Naser, Islam, Syed

Authors: Mohseni, Bahar , Hashemnia, Naser , Islam, Syed
Date: 2017
Type: Text , Conference proceedings , Conference paper
Relation: 2017 IEEE Power and Energy Society General Meeting, PESGM 2017; Chicago, United States; 16th-20th July 2017 Vol. 2018, p. 1-5
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Description: Predictive maintenance offers substantial benefits for detecting the early signs of power transformer faults before they burgeon into catastrophic failures. Online impulse frequency response analysis is a recently-developed diagnostic method for in service transformer with a promising outlook. This paper aims to propose an online partial discharge detection method the online IFRA test. To emulate the dynamic performance characteristics of in service transformer, 3D finite element model of the transformer is calculated in Maxwell Software. In post processing, the FEM sub-circuit model is exported into an external Maxwell Spice circuit to study the terminal behaviors of the transformer. A pulse signal simulating PD is injected between sections of the LV winding. The S transform is then applied to the recorded input and output signals in healthy and faulty conditions to construct the electrical impedance as well as the time-frequency contours of the transient responses. Also, a mechanical deformation is imposed on the transformer to compare its impact on online IFRA to the impact of internal partial discharge.

Wireless networked dynamic control testbed for power converters in smart home applications

- Islam, Syed, Maxwell, Shawn, Park, Sung-Yeul, Zheng, Shaobo, Gong, Tao, Han, Song

Authors: Islam, Syed , Maxwell, Shawn , Park, Sung-Yeul , Zheng, Shaobo , Gong, Tao , Han, Song
Date: 2017
Type: Text , Conference proceedings , Conference paper
Relation: 32nd Annual IEEE Applied Power Electronics Conference and Exposition, APEC 2017; Tampa, United States; 26th-30th March 2017 p. 1196-1202
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Description: Conventional power converters control pulse width modulation (PWM) signals based on the directly sensed feedback signals or estimated state signals. Recently, information and communication technologies are beginning to integrate power converters into smart grid applications. This paper presents a Hardware-In-The-Loop Testbed using a WirelessHART network for smart home applications in a case study. The main components of the testbed are OP4510 RT-LAB-RCP/HIL systems, Texas Instruments Digital Signal Controllers and AwiaTech wireless modules. In this testbed, wireless based controller is integrated with conventional digital controller. OP4510 is used to simulate power stages of the power converters in real time. Texas Instruments Digital Signal Controllers provide PWM signals from the control loop and communication loop. AwiaTech wireless modules are used to build a WirelessHART network to communicate with power converter from a supervisory program. The case study is to support reactive power in smart home applications using 3 bridgeless unidirectional power factor correction (PFC) converters. For this scenario, supervisor collects reactive power measurement data from the input power node and wirelessly transfers reactive power command values to the home appliances driven by PFC converters. Thus, reactive power demand can be minimized. The experimental result demonstrates the performance of the testbed in different communication delays.

A preliminary study on conversion efficiency improvement of a multi-junction PV cell with MPPT

- Das, Narottam, Wongsodihardjo, Hendy, Islam, Syed

Authors: Das, Narottam , Wongsodihardjo, Hendy , Islam, Syed
Date: 2016
Type: Text , Book chapter
Relation: Smart Power Systems and Renewable Energy System Integration (part of the Studies in Systems, Decision and Control book series) Chapter 4 p. 49-73
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Description: This chapter presents a preliminary study conducted to improve photovoltaic (PV) cell conversion efficiency using MATLAB/Simulink platform. The study uses multi-junction solar cell and investigates the maximum performance compared with a conventional silicon PV cell. Maximum Power Point Tracker (MPPT) is applied to assess the conversion efficiency of the PV system. Study integrates thermoelectric generator (TEG) with PV modules because the PV cells work by converting high frequency irradiation where as a TEG has the ability to convert wasted low frequency heat to the electricity. The combination delivers more power and contributes to enhance the conversion efficiency of a PV system. The simulation results show that a tandem cell can provide a considerable higher power with a conventional PV cell operation.

A travelling wave detector based fault location device and data recorder for medium voltage distribution systems

- Jahromi, Ali, Wolfs, Peter, Islam, Syed

Authors: Jahromi, Ali , Wolfs, Peter , Islam, Syed
Date: 2016
Type: Text , Conference proceedings , Conference paper
Relation: 2016 Australasian Universities Power Engineering Conference, AUPEC 2016; Brisbane, Australia; 25th-28th September 2016 p. 1-5
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Description: This paper presents a hardware design for a Travelling Wave (TW) Detector and data recorder for a three phase Medium Voltage (MV) distribution network. The proposed pole mounted platform consists of a capacitively coupled receiver system, a GPS receiver and a Texas Instruments Delfino 28377 processor based travelling wave detection unit. The data recording system uses an Intel Atom base single board computer, a four channel 10Ms/s analogue to digital converter card along with Wi-Fi and GORS communications links. The proposed system is capable of recording three phase voltages simultaneously with the ability to trigger remotely. The platform is mounted in an IP56 enclosure and can be mounted on the MV distribution poles. The paper provides a brief review of hardware and software developed for the TW detector.

Application of online impulse technique to diagnose inter-turn short circuit in transformer windings

- Mohseni, Bahar, Hashemnia, Naser, Islam, Syed, Zhao, Zhongyong

Authors: Mohseni, Bahar , Hashemnia, Naser , Islam, Syed , Zhao, Zhongyong
Date: 2016
Type: Text , Conference proceedings , Conference paper
Relation: 2016 Australasian Universities Power Engineering Conference, AUPEC 2016; Brisbane, Australia; 25th-28th September 2016 p. 1-4
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Description: Inter-turn short circuit fault is a significant problem in power transformers which if not detected at early stages, can propagate in power networks and eventually burgeon into catastrophic faults and substantial costs. Online frequency response analysis (FRA) is well on its way of becoming a reliable tool for condition monitoring and fault detection of transformer since no disconnection is required to conduct the test. Among the two existing FRA methods, sweep frequency response analysis (SFRA) and impulse frequency response analysis (IFRA), IFRA has reached the potential for online application. This contribution aims to detect interturn short circuit fault through online transfer function monitoring of the power transformer winding using the impulse technique, a method which utilizes a capacitive coupling circuit to inject a controlled high voltage nanosecond pulse into the transformer winding. To this end, 3D finite element electromagnetic analysis and transformer equivalent high frequency electrical model have been used as auxiliary tools to precisely emulate the real transformer operation and investigate the impact of inter-turn short-circuit faults on the transformer equivalent circuit parameters and thereby, transformer online FRA signature. Simulations were performed with two different levels of interturn fault severity. The results show that inter-turn short circuit can be effectively detected with the transformer in service using the impulse method.

Capability, compatibility, and usability evaluation of hardware-in-the-loop platforms for DC-DC converter

- Maxwell, Shawn, Islam, Syed, Hossain, Kamal, Park, Sung-Yeul

Authors: Maxwell, Shawn , Islam, Syed , Hossain, Kamal , Park, Sung-Yeul
Date: 2016
Type: Text , Conference proceedings , Conference paper
Relation: 2016 IEEE Energy Conversion Congress and Exposition, ECCE 2016; Milwaukee, United States; 18th-22nd September 2016 p. 1-6
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Description: This paper evaluates the capability, compatibility, and usability of Hardware-in-the-Loop platforms for DC-DC converter. This was accomplished by interfacing the platforms with a physical power stage as well as a controller. The employed platforms are Hi-Rel Power-pole board, Texas Instruments Digital Controller, RTDS, OPAL-RT, dSPACE, and Typhoon. Two sets of experimentation were performed: the power stage represented by the Power-pole board, RTDS, OPAL-RT, dSPACE, and Typhoon and the controller replaced by TI DSC, RTDS, OPAL-RT, dSPACE, and Typhoon. Three points of evaluation for a testing platform that are of interest to industrial researchers as well as academia are capability (speed or modeling capacity), compatibility (ease of porting models from other platforms), and usability (ease of use of software and hardware). This paper provides an introductory resource for research and education by providing results of a simple buck converter example.

Challenges and opportunities in grid connected commercial scale PV and wind farms

- Islam, Syed

Authors: Islam, Syed
Date: 2016
Type: Text , Conference proceedings , Conference paper
Relation: 9th International Conference on Electrical and Computer Engineering, ICECE 2016; Dhaka, Bangladesh; 20th-22nd December 2016 p. 1-7
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Description: Wind power generation and Solar PV installations continues to grow and are the two key contributors to the large scale variable power generation mix. Utility transmission system operators impose stringent grid codes internationally. Grid code regulations are defined by system operators to outline the rights and responsibilities of all the generators and loads that are connected to the transmission/distribution system. In the past, grid codes did not include any regulations for Wind Power Plants (WPPs) and PV plants as the penetration levels were small. However, the situation has now radically changed as many countries have installed many GW worth of variable power generations. The increased reliance on renewable power generation has raised some serious concerns regarding the negative impacts of large WPPs and PV on the stability of power networks. Modern grid codes require WPPS and PVs not only withstand various grid disturbances but also to contribute to network stability support and ancillary services provision, as do conventional generating units. Solar shading can cause PV output to drop by as much as 70% in a space of few seconds. This requires strategies for solar smoothing. In this plenary paper, status review, research challenges and opportunities in developing enabling technologies in grid code compliances, solar smoothing, storage and congestion management to maximise renewable energy penetration into the grid are presented.

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