Novel Cost-effective Technique for Continued Operation of Electrical Equipmen...CSCJournals
This research focuses on mitigating voltage sags at the control level through a cost-effective method using mini dynamic sag corrector at low voltage systems and proposing control level embedded solutions for equipment design and modifying the technical aspects of electrical devices to facilitate the control circuit to ride-through voltage sags. Voltage sags also known as “dips” are a common cause of power disturbances. These are temporary voltage drops below 90% of the nominal voltage caused by a sudden increase in loads or short circuits and faults lasting up to 170ms. Voltage sag in distribution networks can adversely affect sensitive electrical equipment in industrial processes, such as production and manufacturing, resulting in substantial financial losses of up to $1.5 million/day. Various types of electrical equipment are susceptible to voltage sags but are not limited to power supplies, relays, contactors, variable frequency drives, and programmable logic controllers. In this method, the cost-effective MiniDySCs were installed in the industrial plant to compensate for the missing voltage in the lines during a sag event. Also, modifications to technical aspects of Contactors, Relays, and VFDs are proposed to provide more robust results for the control circuits to ride through voltage sags even up to 40% of the nominal voltage-drop.
Design and Mitigation Techniques of MV Capacitor Bank Switching Transients on...ijtsrd
This paper presents the techniques to mitigate transients caused by capacitor switching in the distribution system. It includes the theory of capacitive switching transients with different methods of mitigation. The paper uses MATLAB SIMULINK software package to simulate the specific mitigation devices. The mathematical calculations of different parameters such as transient voltages, current, and frequencies for each device are compared with obtained value from the simulations of each case study. Poonam Bhati | Mukesh Kumar Lodha ""Design and Mitigation Techniques of MV- Capacitor Bank Switching Transients on 132 KV Substation"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-4 , June 2019, URL: https://www.ijtsrd.com/papers/ijtsrd25093.pdf
Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/25093/design-and-mitigation-techniques-of-mv--capacitor-bank-switching-transients-on-132-kv-substation/poonam-bhati
Introduction
Power Quality Problems
Power Quality Measurement Devices
Power Quality Terminology
Power Quality Standards
Unbundled Power Quality Services
Power Quality Monitoring
Benefits of Power Quality
Conclusion
References
Novel Cost-effective Technique for Continued Operation of Electrical Equipmen...CSCJournals
This research focuses on mitigating voltage sags at the control level through a cost-effective method using mini dynamic sag corrector at low voltage systems and proposing control level embedded solutions for equipment design and modifying the technical aspects of electrical devices to facilitate the control circuit to ride-through voltage sags. Voltage sags also known as “dips” are a common cause of power disturbances. These are temporary voltage drops below 90% of the nominal voltage caused by a sudden increase in loads or short circuits and faults lasting up to 170ms. Voltage sag in distribution networks can adversely affect sensitive electrical equipment in industrial processes, such as production and manufacturing, resulting in substantial financial losses of up to $1.5 million/day. Various types of electrical equipment are susceptible to voltage sags but are not limited to power supplies, relays, contactors, variable frequency drives, and programmable logic controllers. In this method, the cost-effective MiniDySCs were installed in the industrial plant to compensate for the missing voltage in the lines during a sag event. Also, modifications to technical aspects of Contactors, Relays, and VFDs are proposed to provide more robust results for the control circuits to ride through voltage sags even up to 40% of the nominal voltage-drop.
Design and Mitigation Techniques of MV Capacitor Bank Switching Transients on...ijtsrd
This paper presents the techniques to mitigate transients caused by capacitor switching in the distribution system. It includes the theory of capacitive switching transients with different methods of mitigation. The paper uses MATLAB SIMULINK software package to simulate the specific mitigation devices. The mathematical calculations of different parameters such as transient voltages, current, and frequencies for each device are compared with obtained value from the simulations of each case study. Poonam Bhati | Mukesh Kumar Lodha ""Design and Mitigation Techniques of MV- Capacitor Bank Switching Transients on 132 KV Substation"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-4 , June 2019, URL: https://www.ijtsrd.com/papers/ijtsrd25093.pdf
Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/25093/design-and-mitigation-techniques-of-mv--capacitor-bank-switching-transients-on-132-kv-substation/poonam-bhati
Introduction
Power Quality Problems
Power Quality Measurement Devices
Power Quality Terminology
Power Quality Standards
Unbundled Power Quality Services
Power Quality Monitoring
Benefits of Power Quality
Conclusion
References
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
A Review on Basic Concepts and Important Standards of Power Quality in Power ...Editor IJCATR
This paper deals with the basic of Power quality in power system. In addition basic definition and important concepts was discussed in simple way. This paper also covers the important power quality standards. In addition IEEE, IEC, SEMI and UIE Power quality standards are listed. This paper would be helpful for the UG and PG students to study about the basics of Power quality in electrical engineering.
Analysis of Transformer Loadings and Failure Rate in Onitsha Electricity Dist...Dr. Hachimenum Amadi
This study investigated transformer loadings and failure rate in the Onitsha Electricity Distribution Network by using the Electrical Transient Analysis Program (ETAP) software 12.6 and the Statistical Package for the Social Sciences (SPSS) software 16.0. Data collected over the period 2011-2015 on the distribution network were simulated on ETAP software using the Newton-Raphson (N-R) technique to determine the transformer loadings while responses to 350 copies of questionnaire distributed among the technical staff were statistically analysed on the SPSS software to ascertain the failure rate among transformers in the network. The findings of the study show that during the 5 years period covered by the study, the sampled substations recorded transformer average failure rate of 11.7 %. It was further revealed that besides insulation issues which accounted for 24.2% of all the failures, overload (22.5%) was the next major cause of transformer breakdowns in the distribution network. The study recommends installation of more transformer units, use of high quality transformers, balanced loading of the transformers and proactive inspection and maintenance program of transformers units within the network. The outcome of this work would help electricity utilities provide more reliable and cost effective services to customers.
Matlab/simulink simulation of unified power quality conditioner-battery energ...IJECEIAES
This paper presents performance analysis of Unified Power Quality Conditioner-Battery Energy Storage (UPQC-BES) system supplied by Photovoltaic (PV)-Wind Hybrid connected to three phase three wire (3P3W) of 380 volt (L-L) and 50 hertz distribution system. The performance of supply system is compared with two renewable energy (RE) sources i.e. PV and Wind, respectively. Fuzzy Logic Controller (FLC) is implemented to maintain DC voltage across the capacitor under disturbance scenarios of source and load as well as to compare the results with Proportional Intergral (PI) controller. There are six scenarios of disturbance i.e. (1) non-linear load (NL), (2) unbalance and nonlinear load (Unba-NL), (3) distortion supply and non-linear load (Dis-NL), (4) sag and non-linear load (Sag-NL), (5) swell and non-linear load (Swell-NL), and (6) interruption and non-linear load (Inter-NL). In disturbance scenario 1 to 5, implementation of FLC on UPQC-BES system supplied by three RE sources is able to obtain average THD of load voltage/source current slightly better than PI. Furthermore under scenario 6, FLC applied on UPQC-BES system supplied by three RE sources gives significantly better result of average THD of load voltage/source current than PI. This research is simulated using Matlab/Simulink.
Very few devices are currently installed in
substations without some form of communications connection.
There is a clear trend toward establishing data connectivity via
Ethernet due to generally higher data rates, and cost effective
connections. Whether an application is for Supervisory Control
and Data Acquisition (SCADA), line relaying, remote
engineering access or Synchrophasors, the Intelligent Electronic
Device (IED) is manufactured featuring a variety of
communication ports including RS-232, RS-485, Ethernet, and
fiber that are connected to, and communicating with at least one
other remote device. Protection engineers typically have a
limited role in communication applications, thus they may not
have a full understanding of a communication networks’
capabilities.
This paper is intended to improve the understanding of the
commonly used forms of communication connections used at a
substation. This paper discusses many communication services
found within a substation.. Each area within itself is worthy of a
text books’ worth of attention. The locus of this document is to
extract highlights of each circuit or application type as pertinent
to a protection engineer for the purpose of gaining a better
understanding of the type of circuit and some of the key roles the
application has in a substation environment.
Basic network design considerations and technologies will also be
reviewed to ensure the network is able to support the
performance criteria imposed by the circuit type. Additionally,
this paper provides design considerations for the different forms
of connections mentioned above. Lastly, it this paper provides
guidance on how these circuit types are applied in substation
applications.
After reviewing this paper or attending the presentation, the
relay engineer will have a broader understanding of the different
circuit types, how they are used, understand the cost and benefits
unique to each circuit type, and be able to communicate those
needs effectively with a Telecom or Information Technology
professional.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This document relates to Harmonic analysis. In every electrical system has fundamental frequency and odd and even Harmonic. AS per IEEE519-1992 standard to evaluate the analysis, to each equipment harmonic order list to be modelled as per manufacturer data. odd harmonic total voltage and current distortion. The recommendation described in this document attempts to reduce
the harmonic effects at any point in the entire system by establishing
limits on certain harmonic indices (currents and voltages) at the point of
common coupling (PCC), a point of metering, or any point as long as
both the utility and the consumer can either access the point for direct
measurement of the harmonic indices meaningful to both or can
estimate the harmonic indices at point of interference (POI) through
mutually agreeable methods
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
A Review on Basic Concepts and Important Standards of Power Quality in Power ...Editor IJCATR
This paper deals with the basic of Power quality in power system. In addition basic definition and important concepts was discussed in simple way. This paper also covers the important power quality standards. In addition IEEE, IEC, SEMI and UIE Power quality standards are listed. This paper would be helpful for the UG and PG students to study about the basics of Power quality in electrical engineering.
Analysis of Transformer Loadings and Failure Rate in Onitsha Electricity Dist...Dr. Hachimenum Amadi
This study investigated transformer loadings and failure rate in the Onitsha Electricity Distribution Network by using the Electrical Transient Analysis Program (ETAP) software 12.6 and the Statistical Package for the Social Sciences (SPSS) software 16.0. Data collected over the period 2011-2015 on the distribution network were simulated on ETAP software using the Newton-Raphson (N-R) technique to determine the transformer loadings while responses to 350 copies of questionnaire distributed among the technical staff were statistically analysed on the SPSS software to ascertain the failure rate among transformers in the network. The findings of the study show that during the 5 years period covered by the study, the sampled substations recorded transformer average failure rate of 11.7 %. It was further revealed that besides insulation issues which accounted for 24.2% of all the failures, overload (22.5%) was the next major cause of transformer breakdowns in the distribution network. The study recommends installation of more transformer units, use of high quality transformers, balanced loading of the transformers and proactive inspection and maintenance program of transformers units within the network. The outcome of this work would help electricity utilities provide more reliable and cost effective services to customers.
Matlab/simulink simulation of unified power quality conditioner-battery energ...IJECEIAES
This paper presents performance analysis of Unified Power Quality Conditioner-Battery Energy Storage (UPQC-BES) system supplied by Photovoltaic (PV)-Wind Hybrid connected to three phase three wire (3P3W) of 380 volt (L-L) and 50 hertz distribution system. The performance of supply system is compared with two renewable energy (RE) sources i.e. PV and Wind, respectively. Fuzzy Logic Controller (FLC) is implemented to maintain DC voltage across the capacitor under disturbance scenarios of source and load as well as to compare the results with Proportional Intergral (PI) controller. There are six scenarios of disturbance i.e. (1) non-linear load (NL), (2) unbalance and nonlinear load (Unba-NL), (3) distortion supply and non-linear load (Dis-NL), (4) sag and non-linear load (Sag-NL), (5) swell and non-linear load (Swell-NL), and (6) interruption and non-linear load (Inter-NL). In disturbance scenario 1 to 5, implementation of FLC on UPQC-BES system supplied by three RE sources is able to obtain average THD of load voltage/source current slightly better than PI. Furthermore under scenario 6, FLC applied on UPQC-BES system supplied by three RE sources gives significantly better result of average THD of load voltage/source current than PI. This research is simulated using Matlab/Simulink.
Very few devices are currently installed in
substations without some form of communications connection.
There is a clear trend toward establishing data connectivity via
Ethernet due to generally higher data rates, and cost effective
connections. Whether an application is for Supervisory Control
and Data Acquisition (SCADA), line relaying, remote
engineering access or Synchrophasors, the Intelligent Electronic
Device (IED) is manufactured featuring a variety of
communication ports including RS-232, RS-485, Ethernet, and
fiber that are connected to, and communicating with at least one
other remote device. Protection engineers typically have a
limited role in communication applications, thus they may not
have a full understanding of a communication networks’
capabilities.
This paper is intended to improve the understanding of the
commonly used forms of communication connections used at a
substation. This paper discusses many communication services
found within a substation.. Each area within itself is worthy of a
text books’ worth of attention. The locus of this document is to
extract highlights of each circuit or application type as pertinent
to a protection engineer for the purpose of gaining a better
understanding of the type of circuit and some of the key roles the
application has in a substation environment.
Basic network design considerations and technologies will also be
reviewed to ensure the network is able to support the
performance criteria imposed by the circuit type. Additionally,
this paper provides design considerations for the different forms
of connections mentioned above. Lastly, it this paper provides
guidance on how these circuit types are applied in substation
applications.
After reviewing this paper or attending the presentation, the
relay engineer will have a broader understanding of the different
circuit types, how they are used, understand the cost and benefits
unique to each circuit type, and be able to communicate those
needs effectively with a Telecom or Information Technology
professional.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This document relates to Harmonic analysis. In every electrical system has fundamental frequency and odd and even Harmonic. AS per IEEE519-1992 standard to evaluate the analysis, to each equipment harmonic order list to be modelled as per manufacturer data. odd harmonic total voltage and current distortion. The recommendation described in this document attempts to reduce
the harmonic effects at any point in the entire system by establishing
limits on certain harmonic indices (currents and voltages) at the point of
common coupling (PCC), a point of metering, or any point as long as
both the utility and the consumer can either access the point for direct
measurement of the harmonic indices meaningful to both or can
estimate the harmonic indices at point of interference (POI) through
mutually agreeable methods
The conventional transformer in power infrastructure should be capable of meeting the demand for the load. The conventional transformer is structured and designed to handle high power. Also, the overload capacity of conventional transformers depends on the highest temperature and short-term overload. This paper represents the construction and working of the solid-state transformer which consists of AC to DC and DC to AC conversion which has low overload capability as compared to conventional transformers. Solid-state transformer finding applications in Solar and wind power generation electric vehicle battery management systems because of high-frequency operation, which is not possible in case of conventional transformers also smart transformer, provides flexible control of electric power distribution.
This application note discusses the use of active filters to reduce harmonic currents in installations. Active filters work by providing the harmonic current required by the load instead of it being drawn from the supply.
The major advantage of active filters is that they can be distributed around an electrical network in a decentralized manner, which enhances the effect of filtering. They can be programmed to respond to selected or all harmonic frequencies and quickly adapt to changes in load profile.
Harmonic Voltage Distortions in Power Systems Due to Non Linear LoadsIJAPEJOURNAL
Harmonics are found to have deleterious effects on power system equipments including transformers, capacitor banks, rotating machines, switchgears and protective relays. Transformers, motors and switchgears may experience increased losses and excessive heating. Shunt filters are effective in minimizing voltage distortions. This paper describes the voltage distortions generated by non linear loads. The harmonic specifications such as harmonic factor, characteristic harmonic and non-characteristic harmonic are considered while explaining the paper. ‘MiPower’ software is used to compute the harmonic distortions in a sample power system. Accurate harmonic models are established for a non linear load. To reduce the harmonic voltages impressed upon specific parts of the sample power system, passive filters are installed at two buses. With the implementation of a passive filter at the bus with non linear load, the harmonics are greatly reduced. For the specified power system, at all the buses the total harmonic distortion has been evaluated.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
A DAPTIVE S UPPLY V OLTAGE M ANAGEMENT F OR L OW P OWER L OGIC C IRCU...VLSICS Design
With the rise in demand of portable hand held devic
es and with the rise in application of wireless sen
sor
networks and RFID reduction of total power consumpt
ion has become a necessity. To save power we
operate the logic circuitry of our devices at sub-t
hreshold. In sub-threshold the drain current is
exponentially dependent on the threshold voltage he
nce the threshold variation causes profound variati
on
of I
ON
and I
OFF
the ratio of which affect the speed of a circuit d
rastically. So to mitigate this problem we
present a adaptive power management circuit which w
ill determine the minimum required supply voltage
to meet the timing requirement. Also to reduce the
power overhead and avoid bulky coil and EMI noise
we used the switch capacitor power regulator to reg
ulate and manage power instead of linear dropout
(LDO) and Inductor base switch mode power converter
A Novel Integrated AC-DC Five Level Converter Strategy for Power Factor Corre...IJMTST Journal
Multilevel configuration has the advantage of its simplicity and modularity over the configurations of the other converters. With the application of multilevel converter in the high voltage and large power occasions in recent years, its modulation strategy has become a research hot point in the field of power electronics. The proposed power-factor-correction circuit can achieve unity power factor and ripple-free input current using a coupled inductor. The proposed rectifier can also produce input currents that do not have dead band regions and an output current that is continuous for all load conditions. The features of this converter are that it has lower input section peak current stresses and a better harmonic content than similar converter with a non-interleaved output, the output current is continuous for all load ranges, and the dc bus voltage is less than 450 for all line and load conditions. In this paper, the operation of the new converter is explained, its steady-state characteristics are determined by analysis, and these characteristics are used to develop a procedure for the design of the converter. Hence the simulation results are obtained using MATLAB/SIMULINK software. The proposed system provides a closed loop control for variable output voltage. The SSPFC AC/DC converter can operate with lower peak voltage stresses across the switches and the DC bus capacitors as it is a three-level converter. The proposed concept can be implemented with 5-level for efficient output voltage.
The aim of this paper is to control the speed of DC motor. The main advantage in using a DC
motor is that the Speed-Torque relationship can be varied to almost any useful form. To achieve the
speed control an electronic technique called Pulse Width Modulation is used which generates High and
Low pulses. These pulses vary the speed in the motor. For the generation of these pulses a
microcontroller (AT89c51) is used. As a microcontroller is used to set the speed ranges which is done by
changing the duty cycles time period in the program. This is practical and highly feasible in economic
point of view, and has an advantage of running motors of higher ratings. This paper gives a reliable,
durable, accurate and efficient way of speed control of a DC motor.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
1. May 6, 2003 1
Interpreting IEEE Std 519 and Meeting its
Harmonic Limits in VFD Applications
Copyright Material IEEE
Paper No. PCIC-2003-15
Tony Hoevenaars, P. Eng. Kurt LeDoux, P.E. Matt Colosino
Member IEEE Member, IEEE
Mirus International Inc. Toshiba International Corp. Crescent Power Systems, Inc.
#12, 6805 Invader Cres. 13131 West Little York Rd. 129 Polk St.
Mississauga, ON L5T 2K6 Houston, TX 77041 New Orleans, LA 70124
Canada USA USA
Abstract –
IEEE Std 519 was first introduced in 1981 to provide direction
on dealing with harmonics introduced by static power converters
and other nonlinear loads so that power quality problems could
be averted. It is being applied by consulting engineers and
enforced by Utilities more frequently in recent years as the use
of Variable Frequency Drives and other non-linear loads has
grown.
Two of the more difficult aspects of applying IEEE Std 519 are
(i) determining an appropriate point of common coupling (PCC)
and (ii) establishing a demand current at the design stage. This
is because the standard does not provide a concise definition of
the PCC and the recommended definition of demand current is
a value that can only be determined by measurements taken
after installation.
This paper represents the authors’ best interpretation of IEEE
Std 519. It attempts to provide clarity in the determination of the
PCC and offers a means by which IEEE Std 519 can be applied
at the design stage when the precise demand current is
unknown.
Index Terms —
Point of Common Coupling (PCC): (As found on p75 of IEEE
Std 519-1992) A point of metering, or any point as long as both
the utility and the consumer can either access the point for
direct measurement of the harmonic indices meaningful to both
or can estimate the harmonic indices at point of interference
(POI). Within an industrial plant, the PCC is the point between
the nonlinear load and the other loads.[1]
(As presently defined by IEEE 519 Working Group) The Point
of Common Coupling (PCC) with the consumer/utility interface
is the closest point on the utility side of the customer's service
where another utility customer is or could be supplied. The
ownership of any apparatus such as a transformer that the utility
might provide in the customer’s system is immaterial to the
definition of the PCC.[2]
Short Circuit Ratio (ISC/IL): The ratio of the short circuit
current (ISC) available at the point of common coupling (PCC) to
the maximum fundamental load current (IL).[1]
Maximum Load Current (IL): Is recommended to be the
average current of the maximum demand for the preceding 12
months.[1] (Unfortunately, this value is inherently ambiguous
making it difficult to derive at the design stage when measured
load is not available).
Voltage THD: Total Harmonic Distortion of the voltage
waveform. The ratio of the root-sum-square value of the
harmonic content of the voltage to the root-mean-square value
of the fundamental voltage.[1]
V THD = V2
2
+V3
2
+V4
2
+V5
2
+....
V1
x 100%
Current THD: Total Harmonic Distortion of the current
waveform. The ratio of the root-sum-square value of the
harmonic content of the current to the root-mean-square value
of the fundamental current.[1]
I THD = I 2
2
+I 3
2
+I 4
2
+I 5
2
+....
I 1
x 100%
Current TDD: Total Demand Distortion of the current
waveform. The ratio of the root-sum-square value of the
harmonic current to the maximum demand load current.[1]
I TDD = I 2
2
+I 3
2
+I 4
2
+I 5
2
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Variable Frequency Drive (VFD): A solid-state device that
converts utility power to a variable voltage and frequency in
order to control the speed of a three-phase induction motor.
Drives typically use harmonic generating rectifiers on their front-
end for AC-DC conversion.
2. May 6, 2003 2
I. INTRODUCTION
With their many benefits, Variable Frequency Drives (VFD’s)
have grown rapidly in their usage in recent years. This is
particularly true in the Petrochemical Industry where their use in
pumping and other applications has led to significant energy
savings, improved process control, increased production and
higher reliability.
An unfortunate side effect of their usage however, is the
introduction of harmonic distortion in the power system. As a
non-linear load, a VFD draws current in a non-sinusoidal
manner, rich in harmonic components. These harmonics flow
through the power system where they can distort the supply
voltage, overload electrical distribution equipment (such as
transformers) and resonate with power factor correction
capacitors among other issues.
In order to prevent harmonics from negatively affecting the
Utility supply, IEEE Std 519 has been established as the
‘Recommended Practices and Requirements for Harmonic
Control in Electrical Power Systems’. This standard has been
widely adopted, particularly in North America, but has often
been misinterpreted and/or misapplied creating installations that
have either been expensively overbuilt or critically under
designed.
IEEE Std 519 in 1981 gave simple guidelines for limits on
voltage distortion. In 1992, it more clearly established limits for
both voltage and current distortion. Its 100 pages cover many
aspects of harmonics in very technical detail making it difficult
for the non-expert to decipher and isolate the important aspects
of its implementation. This paper will attempt to simplify
interpretation of the most applicable portions of the standard,
allowing consulting and facility engineers to become more
comfortable with applying the standard where necessary and
appropriate.
In addition, a case study is presented which describes an
application where a passive harmonic filter was used in an
Electrical Submersible Pump application. The filter was applied
to a standard AC PWM Variable Frequency Drive with a 6-pulse
rectifier front-end to meet the limits proposed in IEEE Std 519
while maintaining optimum VFD performance.
II. IEEE STD 519
IEEE Std 519 was introduced in 1981 and was most recently
revised in 1992. It was intended to provide direction on dealing
with harmonics introduced by static power converters and other
nonlinear loads. The list of static power converters is extensive.
It includes power rectifiers, adjustable speed or variable
frequency drives (both AC and DC), switch-mode power
supplies, uninterruptible power supplies and other devices that
convert ac to dc, dc to dc, dc to ac or ac to ac. The standard
recognizes the responsibility of an electricity user to not degrade
the voltage of the Utility by drawing heavy nonlinear or distorted
currents. It also recognizes the responsibility of the Utility to
provide users with a near sine wave voltage.
The standard was written to establish goals for the design of
electrical systems with both linear and nonlinear loads.
Distortion limits for both current and voltage are defined in order
to minimize interference between electrical equipment. It is
presented as a guideline for power system design when
nonlinear loads are present and assumes steady-state
operation.
Sections 4 through 9 of the standard provide quite extensive
discussion on the generation of harmonics, typical system
response to these harmonics, their effects, methods of
reduction, methods of analysis and measurement techniques.
This information can help in developing a better understanding
of the problem and those interested should take some time to
read these sections. This paper will make reference to these
sections when appropriate but will not cover them in detail.
From an electrical users perspective, Section 10 is the most
important section in the standard. It describes the
‘Recommended Practices for Individual Consumers’. The
primary focus of this paper will be on the items in this section
and how they can be applied to VFD applications. Section 11,
which describes ‘Recommended Practices for Utilities’, will not
be discussed.
IEEE Std 519 was intended to be used as a system standard.
The voltage and current harmonic limits presented in the
standard were designed to be applied while taking the entire
system into consideration, including all linear and non-linear
loading. However, many consulting and facility engineers have
found it difficult to apply IEEE Std 519 as a system standard
because detailed information on the system and its loading is
often not available at the design stage. It is therefore, difficult to
accurately determine compliance at this stage. And even when
the information is available, the resources required to do a
proper analysis does not always exist. Further complicating
matters is that the standard applies to the maximum load
current which may be a poor estimate at the design stage.
Therefore, in order to ensure that some harmonic limits are
applied, these engineers have often resorted to applying the
standard on an individual equipment basis. By insisting that the
current harmonic limits be met at the terminals of the non-linear
equipment, compliance on a system basis can be ensured.
Although this approach can be effective, it often requires very
costly and sometimes unreliable treatment equipment that many
VFD manufacturers have been reluctant to integrate into their
product offerings.
III. IEEE STD 519 RECOMMENDED PRACTICES FOR
INDIVIDUAL CONSUMERS
Section 10 of IEEE Std 519 defines the limits for various
harmonic indices that the authors of the standard believe
strongly correlate to harmonic effects. The defined indices are:
1. Depth of notches, total notch area, and distortion of the
bus voltage by commutation notches
2. Individual and total voltage distortion
3. Individual and total current distortion
3. May 6, 2003 3
Table 10.2, p77
Low-Voltage System Classification and Distortion Limits
Special
Applications1
General
System
Dedicated
System2
Notch Depth 10% 20% 50%
THD (voltage) 3% 5% 10%
Notch Area (AN)3 16 400 22 800 36 500
NOTE: The Value AN for other than 480 V systems should be multiplied by V/480
1 Special applications include hospitals and airports
2 A dedicated system is exclusively dedicated to the converter load
3 In volt-microseconds at rated voltage and current
Figure 1: Table of voltage distortion limits in IEEE Std 519
Table 10.3, p78
Current Distortion Limits for General Distribution Systems
(120 V Through 69,000 V)
Maximum Harmonic Current Distortion in Percent of IL
Individual Harmonic Order (Odd Harmonics)
ISC/IL <11 11≤h<17 17≤h<23 23≤h<35 35≤h TDD
<20* 4.0 2.0 1.5 0.6 0.3 5.0
20<50 7.0 3.5 2.5 1.0 0.5 8.0
50<100 10.0 4.5 4.0 1.5 0.7 12.0
100<1000 12.0 5.5 5.0 2.0 1.0 15.0
>1000 15.0 7.0 6.0 2.5 1.4 20.0
Where:
ISC = maximum short-circuit current at PCC.
IL = maximum demand load current (fundamental frequency
component) at PCC.
Figure 2: Table of current distortion limits in IEEE Std 519
The philosophy adopted to develop the limits for these indices
was to restrict harmonic current injection from individual
customers so that they would not cause unacceptable voltage
distortion levels when applied to normal power systems.
Notches and voltage distortion are presented in a single table,
Table 10.2, ‘Low-Voltage System Classification and Distortion
Limits’. Current distortion limits are found in 3 separate tables
based on bus voltage levels. Table 10.3 is applied to
distribution systems of 120 V to 69,000 V. Table 10.4 is 69,001
V to 161,000 V and Table 10.5 is > 161 kV. Since essentially all
VFD applications fall into the 120 V to 69,000 V range, only
Table 10.3 will be analyzed in this paper.
IV. IEEE STD 519 VOLTAGE HARMONIC LIMITS
Table 10.2 in IEEE Std 519 establishes harmonic limits on
voltage as 5% for total harmonic distortion and 3% of the
fundamental voltage for any single harmonic (see Figure 1).
The justification for these limits is not fully explained but a
reference in Section 6.6 states that:
“Computers and allied equipment, such as programmable
controllers, frequently require ac sources that have no more
than a 5% harmonic voltage distortion factor, with the largest
single harmonic being no more than 3% of the fundamental
voltage. Higher levels of harmonics result in erratic, sometimes
subtle, malfunctions of the equipment that can, in some cases,
have serious consequences. Instruments can be affected
similarly, giving erroneous data or otherwise performing
unpredictably. Perhaps the most serious of these are
malfunctions in medical instruments.”[1]
The reference to medical equipment sensitivity provides some
indication as to why the limits are even more severe (less than
3% VTHD) for special applications such as hospitals and airports
(see note 1 in Figure 1). In contrast, the limits are relaxed (VTHD
< 10%) for dedicated systems. A dedicated system is defined
as one that is exclusively dedicated to converter loads assuming
the equipment manufacturer will allow for operation at these
higher distortion levels.
For applications in the petrochemical industry, the general
system limits are most appropriate. This means that we must
design our systems for < 5% VTHD and with no single harmonic
greater than 3%. These generally will be met at the PCC
provided the current harmonic limits are met.
It should be noted that even if the voltage distortion limits are
met at the PCC, they could very easily be exceeded
downstream where connected equipment could be affected.
Since voltage distortion is the result of harmonic currents
passing through the impedance of the power system, voltage
distortion will always be higher downstream where the harmonic
currents are generated and where system impedance is
highest.[3]
V. IEEE STD 519 CURRENT HARMONIC LIMITS
The level of harmonic voltage distortion on a system that can
be attributed to an electricity consumer will be the function of the
harmonic current drawn by that consumer and the impedance of
the system at the various harmonic frequencies. A system’s
impedance can be represented by the short circuit capacity of
that system since the impedance will limit current that will be fed
into a short circuit. Therefore, the short circuit capacity can be
used to define the size and influence of a particular consumer
on a power system. It can be used to reflect the level of voltage
distortion that current harmonics produced by that consumer
would contribute to the overall distortion of the power system to
which it is connected.
To define current distortion limits, IEEE Std 519 uses a short
circuit ratio to establish a customers size and potential influence
on the voltage distortion of the system. The short circuit ratio
(ISC/IL) is the ratio of short circuit current (ISC) at the point of
common coupling with the utility, to the customer’s maximum
load or demand current (IL). Lower ratios or higher impedance
systems have lower current distortion limits to keep voltage
distortion at reasonable levels.
For power systems with voltage levels between 120 V and
69,000 V, the limits can be found in Table 10.3 of the standard
(see Figure 2). The table defines Total Demand Distortion
(current) limits as well as individual harmonic current limits. The
limits are most severe for short circuit ratios of less than 20
because this lower ratio indicates a high impedance power
system or a large customer or both. Voltage distortion is more
likely to develop from current harmonics consumed at a PCC
where the short circuit ratio is low, thereby justifying the more
severe limits.
VI. DETERMINING AN APPROPRIATE POINT OF
COMMON COUPLING (PCC)
4. May 6, 2003 4
Load RMS 60 Hz 5th 7th 11th 13th ITHD ITDD
Full 233 182 118 80 12 12 79% 79%
75% 187 142 96 70 15 7 86% 65%
50% 134 96 69 54 17 5 96% 48%
25% 67 43 33 29 14 9 120% 30%
Current Harmonics (amps)Current (amps)
Figure 3: Current measurements on a 150HP, 6-pulse VFD with
no harmonic treatment
One of the most difficult aspects to applying IEEE Std 519 is
determining the location of the Point of Common Coupling or
PCC. Since the original objective of IEEE Std 519 was to
prevent the proliferation of non-linear loads from creating power
system problems and in particular voltage distortion, the limits
were intended to be applied at the point where a high level of
harmonics generated by one customer could distort the power
system to a level that might affect other customers on the power
grid.
The concept of PCC has been used to define this point but
unfortunately, the existing standard has not provided a clear
definition. Two definitions are provided in the earlier ‘Index
Terms’ section. The first is as found in Section 10 of IEEE Std
519. It has been found to be too ambiguous to be effectively
applied on a consistent basis therefore, the 519 Working Group
has provided a second definition which can be found on their
website.
The second definition is more precise in that it stipulates that
the PCC is ‘the closest point on the utility side of the customer's
service where another utility customer is or could be supplied’.
It also points out that the ownership of any supply transformer is
irrelevant. That is, if a supply transformer connected to the
public power grid supplies only one customer, the PCC will be
located at the primary of that transformer, rather than the
secondary, regardless of whether the transformer is owned by
that customer or the utility. This is an important distinction
because the transformer’s impedance will decrease the short
circuit ratio and consequently increase the harmonic current
limits. Also, voltage distortion will be higher on the secondary
side of the transformer making it more difficult to meet the
voltage distortion limits.
Although applying IEEE Std 519 limits at the transformer
primary is allowed, good engineering practice should include
consideration of the secondary side voltage distortion. Voltage
distortion will always be higher downstream near the harmonic
generating loads and therefore, meeting IEEE Std 519 limits at
the PCC will not necessarily ensure that voltage distortion is
less than 5% throughout the power distribution system.
VII. HOW TO ESTABLISH A DEMAND CURRENT
DURING THE DESIGN STAGE
Maximum load current (or demand current), as used in the
short circuit ratio (ISC/IL) and Total Demand Distortion (TDD)
calculations, is given a recommended, rather than firm,
definition in IEEE Std 519. It is recommended to be the average
current of the maximum demand for the preceding 12 months.
Unfortunately since this definition is a measured value, it is
totally dependent upon the operating mode of the application,
which makes determination at the design stage extremely
difficult, if not impossible. Also, since the performance of many
treatment methods will vary significantly with loading, designing
an installation that will meet the limits under any and all
operating conditions is very challenging when this definition is
used.
What then should be used? It seems more practical to use
the full load rated current of the non-linear load and apply a
treatment method whose performance level does not degrade
too severely under lighter loading conditions. This strategy is
effective because, in general, a loads maximum contribution to
harmonic distortion (both current and voltage) occurs when
operating at full load. If percent current total harmonic distortion
(ITHD) was the same at all load levels, a non-linear load running
at rated current would draw more harmonic current than it would
while running at a lighter load. And although ITHD normally
increases as loading decreases, a non-linear load will draw less
harmonic current at lighter loads even when the ITHD is higher
provided the increase is proportionately less than the load
decrease.
Figure 3 shows measurements taken on a 150HP, 6-pulse
VFD that has had no harmonic treatment. As percent loading
decreases, ITHD increases but the magnitude of the individual
harmonic currents decreases. Since both voltage distortion and
harmonic overheating are the result of the ampere level of the
harmonic currents, they will be worse at full load operation even
though the ITHD is higher at the lighter loads. Therefore if
treatment applied to the VFD resulted in IEEE Std 519 limits
being met at full load operation, then both voltage distortion and
overheating would be satisfied at all load levels.
If we accept the premise that maximum load current should
be the full rated current of the non-linear load, then we can
determine current total demand distortion (ITDD) and apply the
limits found in Table 10.3 of the standard at the design stage.
Total demand distortion is defined as ‘the ratio of the root-sum-
square value of the harmonic current to the maximum demand
load current’ (see ‘Index Terms’). Therefore at rated load, ITDD
and ITHD are the same value. As load drops, the value of ITDD
relative to ITHD will drop proportionately with the load. For
example, if ITHD is 96% at 50% loading, then ITDD at that load
would be ½ that value or 48% (see Figure 3).
VIII. CASE STUDY
Location: Amerada Hess Corporation, Tioga, ND
Application: Down Hole Electrical Submersible Pump (ESP)
VFD: 200HP, 480V AC PWM VFD
Harmonic Filter: 200HP, 480V series connected passive
LC filter
The VFD was operating as part of an Electrical Submersible
Pump (ESP) installation in a remote area of North Dakota. It
was equipped with a built-in DC link reactor which reduced the
harmonic currents reflected back into the power system by
approximately 2 times. However, even at this reduced level, the
5. May 6, 2003 5
Input Current Waveform
w/o Harmonic Filter with Harmonic Filter
Figure 4: Input Current Waveform with and without
harmonic filter
harmonic currents generated by the VFD exceeded the limits as
defined by IEEE Std 519, Table 10.3.
The Utility provided three 100 kVA, 12.5kV-480V 1-ph
transformers with an impedance of 2.6% to supply the 200HP
VFD. Fault current, Isc, on the primary side was 900A and
8,700A on the secondary side. The Utility was not specific as to
the location of the PCC so both primary and secondary
locations were considered.
Even without the installation of harmonic treatment, voltage
distortion (VTHD) was comfortably below IEEE std 519 limits.
VTHD on the secondary side of the transformer was measured at
3.4% (< 5% limit) with the largest harmonic being the 5th
at 2.3%
(< 3% limit). Even though measurements could not be taken
on the primary side because the measuring instrumentation was
not suitably rated for the higher voltage, meeting the limits on
the secondary side ensured that they were being met on the
primary side. This is because the transformers impedance
always results in higher voltage distortion on its secondary side
than on its primary side.
To determine whether current distortion limits were met, the
short circuit ratio was calculated.
For PCC at primary:
ISC = 900A
IL = 7A (full load 60 Hz current)
ISC/IL = 128
From Table 10.3, ITDD <15%
For PCC at secondary:
ISC = 8,700A
IL = 180A (full load 60 Hz current)
ISC/IL = 48
From Table 10.3, ITDD <8%
Current THD (ITHD) at the secondary of the transformer before
installation of the Lineator filter was measured to be 35% when
operating at 60% load which was the maximum operating load
attainable at the time. Since the load current contained no zero
sequence harmonic currents, the primary side ITHD could be
assumed to be essentially the same as the secondary side.
Using full load current rating as the peak demand, ITDD was
calculated to be 21% (35% x .6) which exceeded the IEEE 519
maximum limits on both the primary (15%) and the secondary
(8%).
With the harmonic filter installed, ITHD dropped to 5.4% which
was comfortably below the IEEE Std 519 limit at both the
primary and secondary even without calculating ITDD based on
full load rating. Figure 4 shows the input current waveforms
both with and without the harmonic filter. With the filter, current
is virtually sinusoidal with a much lower peak level than without
the filter.
One other benefit of the filter installation was a reduction in
Radio Frequency Interference (RFI) which eliminated an AM
reception problem experienced by a neighboring farmer.
IX. CONCLUSIONS
Applying the harmonic limits as defined in IEEE Std 519 to
VFD applications is a useful exercise but often a challenging
one. Most VFD suppliers and filter manufacturers can help by
running a power system harmonic analysis for a specific
application to determine THD levels at the point of common
coupling. This analysis can be developed considering various
harmonic attenuation methods while comparing hardware
requirements, performance and cost.
It is also important to keep in mind that the entire power
system comes into play when analyzing performance and
reliability. For example, a ‘weak’ power system using onsite
generation may not have the voltage and frequency stability to
work in conjunction with an active filter or some passive filters
with high capacitive reactance. Experience has also shown that
drive performance can sometimes be impacted as the system
architecture is modified in an attempt to lower THD levels. For
critical systems, on-site performance testing may be helpful.
Overall, it is important to understand how the various system
components interact with each other and with the power system.
It is essential that a coordinated solution be provided which
meets THD levels, system performance demands and power
system requirements. Fixing a harmonic distortion problem in
the field after installation can be difficult, time consuming and
expensive.
V. ACKNOWLEDGEMENTS
Alan Hartwell, Amerada Hess Corporation, Williston, ND
VI. REFERENCES
[1] IEEE Std 519-1992, IEEE Recommended Practices and
Requirements for Harmonic Control in Electrical Power
Systems, New York, NY: IEEE.
[2] IEEE Std 519 Working Group Website,
http://grouper.ieee_org/groups/519
[3] A. H. Hoevenaars, “The Answer to Harmonics: Is it
Mitigation or a Robust Transformer?”, CEE News – The
Power Quality Advisor, pp PQ14-17, February 2000.
[4] I. C. Evans, “Methods of Mitigation”, Middle East
Electricity, pp 25-26, December 2002.
6. May 6, 2003 6
VIII. VITA
Tony Hoevenaars is Vice President of MIRUS International
Inc., a company specializing in the treatment of power system
harmonics. Prior to joining MIRUS in 1996, Tony was the Chief
Facilities Electrical Engineer at an IBM manufacturing facility in
Toronto where he gained extensive experience in solving power
quality related problems, particularly in the area of harmonics.
He graduated from the University of Western Ontario, London
ON Canada with a BESc degree in 1979. He is a Professional
Engineer, member of IEEE and has published numerous papers
on power quality.
Kurt LeDoux is an electrical engineer that has worked for
Toshiba for more than 20 years in all aspects of AC and DC
motor speed control. He presently works as a Product Manager
in marketing of Medium Voltage Drives. Previous positions in
the company were in technical writing, field service, quality
control, and low voltage AC drive marketing.
Matt Colosino is Owner of Crescent Power System, a
company specializing in providing industrial grade power
systems and the application of adjustable speed drives.
Crescent Power Systems services the refining, chemical,
production, pipeline, material handling, mining, pulp, paper,
water and waste water industries. Matt has a BSEE from Tulane
University and has been involved in the sales and service of
electrical power systems for over 23 years.