A Magnetic linked modular cascaded multilevel converter for medium voltage grid applications
- Authors: Hasan,Md Mubashwar , Islam, Syed , Abu-Siada, Ahmed , Islam, Rabiul Md
- Date: 2019
- Type: Text , Conference proceedings
- Relation: 2019 29th Australasian Universities Power Engineering Conference (AUPEC); Nadi, Fiji; 26-29 November 2019
- Full Text: false
- Reviewed:
- Description: One of the key advantages of cascaded multilevel inverters (CMLI) is their ability to generate medium voltage output by using low voltage rated circuit components. For this reason, CMLI has been given much attention in renewable and industrial applications. However, in spite CMLI advantages, balanced input dc voltage management at the cascaded cells is still considered one of the main drawbacks, which limits its straightforward applications. Moreover, galvanic isolation between the input dc supply and the inverter output voltage is essential for grid-connected application. In such case, a step-up transformer is utilized between the inverter output terminals and the grid. This solution incurs additional cost, increases implementation size, weight and maintenance. In this paper, a CMLI is proposed for medium voltage applications by utilizing high frequency magnetic link to ensure galvanic isolation without the need to a conventional step-up transformer as per the current practice. 3 rd harmonic-injected sine pulse width modulation strategy is adopted as a switching controller for the proposed cascaded inverter that is implemented and tested. Experimental results attest the simulation results and confirm the feasibility of the proposed inverter
A new control approach to improve the overall performance of DFIG-based WECS
- Authors: Khamaira, Mahmoud , Abu-Siada, Ahmed , Islam, Syed , Masoum, Mohammad
- Date: 2014
- Type: Text , Conference proceedings , Conference paper
- Relation: 24th Australasian Universities Power Engineering Conference, AUPEC 2014; Perth, Australia; 28th September-1st October 2014 p. 1-5
- Full Text: false
- Reviewed:
- Description: Doubly Fed Induction Generators (DFIGs) are currently extensively used in variable speed wind power plants due to their superior advantages that include reduced converter rating, low cost, reduced losses, easy implementation of power factor correction schemes, variable speed operation and four quadrants active and reactive power control capabilities. On the other hand, DFIG sensitivity to grid disturbances, especially for voltage sags represents the main disadvantage of the equipment. In this paper, a coil is proposed to be integrated within the DFIG converters to improve the overall performance of a DFIG-based wind energy conversion system (WECS). A proportional integral (PI) controller to control the charging and discharging of the coil is introduced. Simulation results reveal the effectiveness of the proposed topology in improving the overall performance of the WECS under study.
A novel generalized concept for three phase cascaded multilevel inverter topologies
- 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
- Full Text: false
- Reviewed:
- 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 review on chemical diagnosis techniques for transformer paper insulation degradation
- Authors: Abu Bakar, Norazhar , Abu Siada, Ahmed , Islam, Syed
- Date: 2013
- Type: Text , Conference proceedings , Conference paper
- Relation: 2013 Australasian Universities Power Engineering Conference, AUPEC 2013; Hobart, Australia; 29th September-3rd October 2013 p. 1-6
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- Description: Energized parts within power transformer are isolated using paper insulation and are immersed in insulating oil. Hence, transformer oil and paper insulation are essential sources to detect incipient and fast developing power transformer faults. Several chemical diagnoses techniques are developed to examine the condition of paper insulation such as degree of polymerization, carbon oxides, furanic compounds and methanol. The principle and limitation of these diagnoses are discussed and compared in this paper.
A three dimensional imaging-based framework for planning maxillomandibular advancement surgery for the treatment of obstructive sleep apnoea
- Authors: Islam, Syed , Goonewardene, Mithran , Bennamoun, Mohammed , Lucey, Anthony , Farella, Mauro , Abduo, Jaafar , Cisonni, Julien
- Date: 2013
- Type: Text , Conference proceedings , Conference paper
- Relation: 2013 4th World Congress on Software Engineering, WCSE 2013; Hong Kong, China; 3rd-4th December 2013 p. 301-306
- Full Text: false
- Reviewed:
- Description: Obstructive Sleep Apnoea (OSA), a sleeping disorder, is a serious health issue with significant public health implications. Due to the interrupted sleep, OSA patients suffer with excessive day-time sleepiness, fatigue and other health complexities that lead to on-road and work-related accidents and incur billions of dollars per year. Traditionally, treatment of OSA begins with nasal continuous positive airway pressure (CPAP). Alternatively, Mandibular Repositioning Appliances or surgical interventions can be used. Although Maxillomandibular Advancement (MMA) surgery is often advised as the last line of treatment due to the expense and significant changes in the facial appearance, it is the only permanent solution to OSA with a definitive outcome especially for the patients with significant facial deformation or anomalies. In this article, three dimensional (3D) image-guided predictive algorithms are proposed to improve the treatment planning and overall outcome of the MMA surgery. 3D analysis of the facial surface data and Computational Biomechanics-based 3D modelling of airway segmented from Cone Beam Computed Tomography (CBCT) data are proposed to predict the required physiological changes to ensure optimal air-flow through the airway. Moreover, 3D Computer Graphics-based techniques are proposed to visualise and demonstrate the expected facial outcomes to inform patients and surgeons prior to this non-reversible surgery.
A three-phase half-bridge cascaded inverter with reduced number of input DC supply
- 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
- Full Text: false
- Reviewed:
- 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.
A travelling wave detector based fault location device and data recorder for medium voltage distribution systems
- 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
- Full Text: false
- Reviewed:
- 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.
Alleviating post-contingency congestion risk of wind integrated systems with dynamic line ratings
- Authors: Banerjee, Binayak , Jayaweera, Dilan , Islam, Syed
- Date: 2014
- Type: Text , Conference proceedings , Conference paper
- Relation: 24th Australasian Universities Power Engineering Conference, AUPEC 2014; Perth, Australia; 28th September-1st October 2014 p. 1-6
- Full Text: false
- Reviewed:
- Description: One of the factors hindering the large scale integration of wind power is the post contingency congestion of a network due to limited availability of network capacity and auxiliary constraints. Under such conditions, the network operators can potentially request a curtailment of wind farm output if the remedial strategies fail. The paper investigates this problem in detail and proposes a mathematical framework to capture the post contingency spare capacity of network assets that is required to limit the wind curtailment. The proposed approach incorporates stochastic variation in asset thermal rating; models network congestion, and quantifies the risk of congestion using an extended version of conic-quadratic programming based optimization. The uniqueness of the proposed mathematical model is that it converts conventional thermal constraints to dynamic constraints by using a discretized stochastic penalty function with quadratic approximation of constraint relaxation penalty. The results suggest that the wind utilization can be maximized if the networks are operated 30-50% less than the nominal rating of the assets.
An experimental thermographic safety audit focusing on temperature rise vs load in electrical installations in a Bangladesh garments factory
- 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
- Full Text: false
- Reviewed:
- 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.
Analysis of end-to-end delay characteristics for various packets in IEC 61850 substation communications system
- Authors: Das, Narottam , Ma, Wu , Islam, Syed
- Date: 2015
- Type: Text , Conference proceedings , Conference paper
- Relation: 25th Australasian Universities Power Engineering Conference, AUPEC 2015, Wollongong, Australia; 27th-30th September 2015 p. 1-5
- Full Text:
- Reviewed:
- Description: Substation plays an important role in power system communications for safe and reliable operation of entire power networks. Substation communication networks are connected with various substation intelligent electronic devices (IEDs), which is substation systems lifeblood and the system availability is decided by its real-Time performance. International Electro-Technical Commission (IEC) has been developed the standards based on object-oriented technologies for substation automation. IEC 61850 protocol has been applied widely in substation communication applications. It presents new challenges to realtime performance simulation and testing of protective relays. In this paper, an optimized network engineering tool (OPNET) or Riverbed modeler simulation tool/ software has been used for the modeling of IED in substation level network. Based on the simulation results, different types of data stream have been discussed, such as, periodic data stream, random data stream and burst data steam. The typical studies using these models, to construct substation automation system (SAS) network on the OPNET modeler or Riverbed modeler was made to reveal the impact of each affecting parameter or factor to the real-Time performance of substation communications system, which is also incorporated in this report.
- Description: 2015 Australasian Universities Power Engineering Conference: Challenges for Future Grids, AUPEC 2015
Analysis of IEC 61850 for a Reliable Communication System between Substations
- Authors: Yang, Xin , Das, Narottam , Islam, Syed
- Date: 2013
- Type: Text , Conference proceedings , Conference paper
- Relation: 2013 Australasian Universities Power Engineering Conference, AUPEC 2013; Hobart, Australia; 29th September-3rd October 2013 p. 1-6
- Full Text: false
- Reviewed:
- Description: IEC 61850 Standard was introduced to address the challenge presented by existence of the multiple protocols in substation communications, which include many proprietary protocols; and to address the challenge introduced by legacy complicated substation from both cost and complicity. In this paper, the simulation results of different types of IEC 61850 network system configurations using OPNET Modeler simulation software were presented and the influence on data rate and delay characteristics of these system configurations were evaluated. The simulated results confirm that the ring configured system suitable for higher loading characteristics and higher system reliability.
Analysis of incident light angles on nan-grating structure for minimizing reflection losses in GaAs solar cells
- Authors: Das, Narottam , Charoenpitaks, Korawat , Islam, Syed
- Date: 2013
- Type: Text , Conference proceedings , Conference paper
- Relation: 2013 Australasian Universities Power Engineering Conference, AUPEC 2013; Hobart, Australia; 29th September-3rd October 2013 p. 1-6
- Full Text: false
- Reviewed:
- Description: Subwavelength grating (SWG) structures make an excellent alternative antireflective (AR) coating due to its capacity to reduce the reflection losses in GaAs solar cells. The SWG structures allow the gradual change in refractive index that confirms an excellent AR coating and the light trapping properties when compare with planar thin film structures. Finite-difference time domain (FDTD) method is used to simulate the reflection losses of the SWG structure in GaAs solar cells. The FDTD simulation results show that the slightly change of incident angle affect the reflection losses of all nano-grating structure. The simulation results also confirmed that the reflection loss of nano-grating structure maintained optimum within ~±5° of incident angle tolerance for the grating height over 300-nm for minimizing the reflection losses in GaAs solar cells.
Analysis of power system communication architectures between substations using IEC 61850
- Authors: Das, Narottam , Islam, Syed
- Date: 2014
- Type: Text , Conference proceedings , Conference paper
- Relation: 5th Brunei International Conference on Engineering and Technology, BICET 2014; Bandar Seri Begawan, Brunei Darussalam; 1st-3rd November 2014 Vol. 2014, p. 1-6
- Full Text: false
- Reviewed:
- Description: Interoperability among multi-vendor substations automation devices, is now achievable due to the introduction of IEC 61850 standard, which allows power system communication between substations. This standard does not mandatorily demands for redundancy in any type of substation neither does it mentions a specific type of substation design application. Ethernet based communication protocols for substation automation systems (SASs) are specified in IEC 61850 standard. The standards include Ethernet based process-level connections between switchyards and control rooms. However, their in-service performance is not well known. Moreover, IEC 61850 demands for a communication topology which is zero point failure proof and provides worthy data transmission rates, without pursuing any delays. In order to achieve these norms, Ethernet architectures must be modelled and analysed in detail. The performance of individual architecture must be analysed in terms of their reliability, availability and efficiency of data transfer. This paper presents the reliability and availability using the reliability block diagrams, along with OPNET network real-time simulations, which shows the efficiency of individual architecture along with comparing and synthesizing the most effective communication topology for the SASs.
Application of digital image processing to diagnose transformer winding deformation using FRA polar plot
- Authors: Aljohani, Omar , Abu-Siada, Ahmed , Islam, Syed
- Date: 2014
- Type: Text , Conference proceedings , Conference paper
- Relation: 2014 International Conference on Condition Monitoring and Diagnosis, CMD 2014; Jeju, Korea; 21st September 2014
- Full Text: false
- Reviewed:
- Description: Digital image processing (DIP) technique has been growing rapidly as an essential tool to interpret various image features for many applications of science and engineering. Condition monitoring and diagnosis are considered the main areas that relay on DIP. Frequency response analysis (FRA) technique has become a popular and reliable diagnostic tool in detecting various winding deformations within power transformers. However, interpretation of FRA signatures still requires high expertise because of its reliance on graphical analysis. This paper presents a new technique for the interpretation of transformers FRA signatures. The proposed technique relies on incorporating both magnitude and angle of the FRA signature in one polar plot, which is manipulated to extract some unique features using DIP techniques. The proposed technique can assess in identifying and quantifying various winding deformation within power transformers. The proposed technique is easy to implement in any frequency response analyser.
Application of online impulse technique to diagnose inter-turn short circuit in transformer windings
- 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
- Full Text: false
- Reviewed:
- 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.
Application of S transform for detection of external interferences in online transformer impulse frequency response analysis
- 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
- Full Text: false
- Reviewed:
- 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.
Application of SMES unit to improve the overall performance of DFIG-based WECS
- Authors: Khamaira, Mahmoud , Abu-Siada, Ahmed , Islam, Syed , Masoum, Mohammad
- Date: 2014
- Type: Text , Conference proceedings , Conference paper
- Relation: 2014 IEEE Power and Energy Society General Meeting; National Harbor, United States; 27th-31st July 2014 Vol. 2014, p. 1-5
- Full Text: false
- Reviewed:
- Description: Doubly Fed Induction Generators (DFIGs) are nowadays extensively used in variable speed wind power plants due to their advantages that include reduced converter rating, low cost, reduced losses with an improved efficiency, easy implementation of power factor correction schemes, variable speed operation and four quadrants active and reactive power control capabilities. On the other hand, DFIG sensitivity to grid disturbances, especially for the voltage dip represents the main disadvantage of the equipment. This paper presents the application of superconducting magnetic energy storage (SMES) unit to improve the overall performance of a DFIG-based wind energy conversion systems (WECS). Two control approaches namely; hysteresis current controller (HCC) along with proportional integral (PI) controller and a fuzzy logic (FL) controller for the SMES unit are presented and compared. Various grid codes are used to examine the capability of the two proposed controllers to improve the low voltage ride through (LVRT) capability of the DFIG to maintain the wind turbine connection to the grid through fault durations.
- Description: IEEE Power and Energy Society General Meeting
Assessing transformer oil quality using deep convolutional networks
- Authors: Alam, Mohammad , Karmakar, Gour , Islam, Syed , Kamruzzaman, Joarder , Chetty, Madhu , Lim, Suryani , Appuhamillage, Gayan , Chattopadhyay, Gopi , Wilcox, Steve , Verheyen, Vincent
- Date: 2019
- Type: Text , Conference proceedings , Conference paper
- Relation: 29th Australasian Universities Power Engineering Conference, AUPEC 2019
- Full Text:
- Reviewed:
- Description: Electrical power grids comprise a significantly large number of transformers that interconnect power generation, transmission and distribution. These transformers having different MVA ratings are critical assets that require proper maintenance to provide long and uninterrupted electrical service. The mineral oil, an essential component of any transformer, not only provides cooling but also acts as an insulating medium within the transformer. The quality and the key dissolved properties of insulating mineral oil for the transformer are critical with its proper and reliable operation. However, traditional chemical diagnostic methods are expensive and time-consuming. A transformer oil image analysis approach, based on the entropy value of oil, which is inexpensive, effective and quick. However, the inability of entropy to estimate the vital transformer oil properties such as equivalent age, Neutralization Number (NN), dissipation factor (tanδ) and power factor (PF); and many intuitively derived constants usage limit its estimation accuracy. To address this issue, in this paper, we introduce an innovative transformer oil analysis using two deep convolutional learning techniques such as Convolutional Neural Network (ConvNet) and Residual Neural Network (ResNet). These two deep neural networks are chosen for this project as they have superior performance in computer vision. After estimating the equivalent aging year of transformer oil from its image by our proposed method, NN, tanδ and PF are computed using that estimated age. Our deep learning based techniques can accurately predict the transformer oil equivalent age, leading to calculate NN, tanδ and PF more accurately. The root means square error of estimated equivalent age produced by entropy, ConvNet and ResNet based methods are 0.718, 0.122 and 0.065, respectively. ConvNet and ResNet based methods have reduced the error of the oil age estimation by 83% and 91%, respectively compared to that of the entropy method. Our proposed oil image analysis can calculate the equivalent age that is very close to the actual age for all images used in the experiment. © 2019 IEEE.
- Description: E1
Assessment of distributed generation capacity mixture for hybrid benefits
- Authors: Jayaweera, Dilan , Islam, Syed , Neduvelil, Sandeep
- Date: 2013
- Type: Text , Conference proceedings , Conference paper
- Relation: 22nd International Conference and Exhibition on Electricity Distribution, CIRED 2013; Stockholm, Sweden; 10th-13th June 2013 Vol. 2013, p. 1-4
- Full Text: false
- Reviewed:
- Description: The distributed generation (DG) mixture in an active distribution network can provide different levels of network benefits and benefits external to the network. This paper investigates this problem in detail and proposes an approach to assess the DG mixture for hybrid benefits through the sequential simulation of optimized samples. A case study is performed incorporating Wind and PV generation as intermittent DG, diesels, their life-cycle costs (LCCs), and contribution to greenhouse-gas (GHG) abatement. Results suggest that specific operating conditions in a network can dominate the DG mixture and deliver the combined benefits. Wind and diesel hybrid operation can be the most beneficial DG mixture in an active distribution network compared to any other DG combination with current costing structure.
Battery impedance measurement using sinusoidal ripple current emulator
- 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
- Full Text: false
- Reviewed:
- 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.