The document discusses transformer metering, heating, and harmonics. It covers harmonic conditions and their effects on three-phase transformers and current transformers. It presents standards for harmonic distortion limits. Finite element analysis was used to model and analyze a three-phase isolation transformer under harmonic conditions. Experimental results validated the finite element model. Temperature rise calculations were also presented for a 2.5MVA three-phase isolation transformer.
SWICTH GEAR AND PROTECTION (2170906)
DISTANCE RELAY
• There are mainly Three types of distance relay
1) Impedance Relay
2) Reactance Relay
3) Mho Relay
We had made a working model on static VAR compensator which is made by power electronic switch and mechanically switched. We had chosen mechanically switched capacitor method to improved receiving end voltage as well as power factor.
Unit I: Introduction to Protection System:
Introduction to protection system and its elements, functions of protective relaying, protective zones, primary and backup protection, desirable qualities of protective relaying, basic terminology.
Relays:
Electromagnetic, attracted and induction type relays, thermal relay, gas actuated relay, design considerations of electromagnetic relay.
Unit-II: Relay Application and Characteristics:
Amplitude and phase comparators, over current relays, directional relays, distance relays, differential relay.
Static Relays: Comparison with electromagnetic relay, classification and their description, over current relays, directional relay, distance relays, differential relay.
Unit-III Protection of Transmission Line:
Over current protection, distance protection, pilot wire protection, carrier current protection, protection of bus, auto re-closing,
Unit-IV: Circuit Breaking:
Properties of arc, arc extinction theories, re-striking voltage transient, current chopping, resistance switching, capacitive current interruption, short line interruption, circuit breaker ratings.
Testing Of Circuit Breaker: Classification, testing station and equipments, testing procedure, direct and indirect testing.
Unit-V Apparatus Protection:
Protection of Transformer, generator and motor.
Circuit Breaker: Operating modes, selection of circuit breakers, constructional features and operation of Bulk Oil, Minimum Oil, Air Blast, SF6, Vacuum and d. c. circuit breakers.
SWICTH GEAR AND PROTECTION (2170906)
DISTANCE RELAY
• There are mainly Three types of distance relay
1) Impedance Relay
2) Reactance Relay
3) Mho Relay
We had made a working model on static VAR compensator which is made by power electronic switch and mechanically switched. We had chosen mechanically switched capacitor method to improved receiving end voltage as well as power factor.
Unit I: Introduction to Protection System:
Introduction to protection system and its elements, functions of protective relaying, protective zones, primary and backup protection, desirable qualities of protective relaying, basic terminology.
Relays:
Electromagnetic, attracted and induction type relays, thermal relay, gas actuated relay, design considerations of electromagnetic relay.
Unit-II: Relay Application and Characteristics:
Amplitude and phase comparators, over current relays, directional relays, distance relays, differential relay.
Static Relays: Comparison with electromagnetic relay, classification and their description, over current relays, directional relay, distance relays, differential relay.
Unit-III Protection of Transmission Line:
Over current protection, distance protection, pilot wire protection, carrier current protection, protection of bus, auto re-closing,
Unit-IV: Circuit Breaking:
Properties of arc, arc extinction theories, re-striking voltage transient, current chopping, resistance switching, capacitive current interruption, short line interruption, circuit breaker ratings.
Testing Of Circuit Breaker: Classification, testing station and equipments, testing procedure, direct and indirect testing.
Unit-V Apparatus Protection:
Protection of Transformer, generator and motor.
Circuit Breaker: Operating modes, selection of circuit breakers, constructional features and operation of Bulk Oil, Minimum Oil, Air Blast, SF6, Vacuum and d. c. circuit breakers.
Functions and Performance Requirements
Elements of an Excitation System
Types of Excitation Systems
Control and Protection Functions
Modeling of Excitation Systems
The functions of an excitation system are
to provide direct current to the synchronous generator field winding, and
to perform control and protective functions essential to the satisfactory operation of the power system
The performance requirements of the excitation system are determined by
Generator considerations:
supply and adjust field current as the generator output varies within its continuous capability
respond to transient disturbances with field forcing consistent with the generator short term capabilities:
rotor insulation failure due to high field voltage
rotor heating due to high field current
stator heating due to high VAR loading
heating due to excess flux (volts/Hz)
Power system considerations:
contribute to effective control of system voltage and improvement of system stability
Introduction to reactive power control in electrical powerDr.Raja R
Introduction to reactive power control in electrical power
Reactive power in transmission line :
Reactive power control
Reactive power and its importance
Apparent Power
Reactive Power
Apparent Power
Reactive Power Formula
Nowadays, it is very important to maintain voltage level. Controlling of that voltage is also important. This Presentation contains methods of voltage control.
With the incoming high penetration of renewable energy systems such as wind farms and solar photovoltaic systems, both electric utilities and end users of electric power are becoming increasingly concerned about the network harmonics.
This has affected the normal operation of transformers, causing undesirable extra power loss and associated temperature rise. Considering transformers are expected to be in service continuously to maintain the electricity supply of the network, there is major concern about the adverse effects of harmonic contamination on the performance and life expectancy of the transformers.
Functions and Performance Requirements
Elements of an Excitation System
Types of Excitation Systems
Control and Protection Functions
Modeling of Excitation Systems
The functions of an excitation system are
to provide direct current to the synchronous generator field winding, and
to perform control and protective functions essential to the satisfactory operation of the power system
The performance requirements of the excitation system are determined by
Generator considerations:
supply and adjust field current as the generator output varies within its continuous capability
respond to transient disturbances with field forcing consistent with the generator short term capabilities:
rotor insulation failure due to high field voltage
rotor heating due to high field current
stator heating due to high VAR loading
heating due to excess flux (volts/Hz)
Power system considerations:
contribute to effective control of system voltage and improvement of system stability
Introduction to reactive power control in electrical powerDr.Raja R
Introduction to reactive power control in electrical power
Reactive power in transmission line :
Reactive power control
Reactive power and its importance
Apparent Power
Reactive Power
Apparent Power
Reactive Power Formula
Nowadays, it is very important to maintain voltage level. Controlling of that voltage is also important. This Presentation contains methods of voltage control.
With the incoming high penetration of renewable energy systems such as wind farms and solar photovoltaic systems, both electric utilities and end users of electric power are becoming increasingly concerned about the network harmonics.
This has affected the normal operation of transformers, causing undesirable extra power loss and associated temperature rise. Considering transformers are expected to be in service continuously to maintain the electricity supply of the network, there is major concern about the adverse effects of harmonic contamination on the performance and life expectancy of the transformers.
The best way to be sure you are getting the correct revenue from a site is to test the entire site. Learn how to find any diversions, corrosion, broken or frayed wiring as well as all the tests you can perform while at a site.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
Automobile Management System Project Report.pdfKamal Acharya
The proposed project is developed to manage the automobile in the automobile dealer company. The main module in this project is login, automobile management, customer management, sales, complaints and reports. The first module is the login. The automobile showroom owner should login to the project for usage. The username and password are verified and if it is correct, next form opens. If the username and password are not correct, it shows the error message.
When a customer search for a automobile, if the automobile is available, they will be taken to a page that shows the details of the automobile including automobile name, automobile ID, quantity, price etc. “Automobile Management System” is useful for maintaining automobiles, customers effectively and hence helps for establishing good relation between customer and automobile organization. It contains various customized modules for effectively maintaining automobiles and stock information accurately and safely.
When the automobile is sold to the customer, stock will be reduced automatically. When a new purchase is made, stock will be increased automatically. While selecting automobiles for sale, the proposed software will automatically check for total number of available stock of that particular item, if the total stock of that particular item is less than 5, software will notify the user to purchase the particular item.
Also when the user tries to sale items which are not in stock, the system will prompt the user that the stock is not enough. Customers of this system can search for a automobile; can purchase a automobile easily by selecting fast. On the other hand the stock of automobiles can be maintained perfectly by the automobile shop manager overcoming the drawbacks of existing system.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
In my system we have to make a system by which a user can record all events coordinated by a particular faculty. In our proposed system some more featured are added which differs it from the existing system such as security.
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.
1. Transformers: Metering, Heating and
Harmonics
Michael Robert Larkin
Managing Director at Tortech Pty Ltd
ENGINEERS
AUSTRALIA
Tortech Pty Ltd
Total Transformer
Solutions
2. Coal Mining Steel Plant
High- Speed Railway Solar & Wind Power Plants2
Tortech Pty Ltd
Total Transformer
Solutions
3. Tortech Pty Ltd
Total Transformer
OUTLINE
Harmonics and three phase
transformers
Three-phase metering units for solar
installation
CT design under power grid harmonic
conditions
Temperature rise calculation of three-
phase isolation transformers
Design of suitable enclosure for three-
phase transformers under harmonic
conditions2
4. Harmonics and three phase transformers
What Are Harmonics?
4
+
+
+
+
50 Hz
(Fundamental
Frequency)
150 Hz
(h=3)
250 Hz
(h=5)
350 Hz
(h=7)
450 Hz
(h=9)
Non-Sinusoidal Signal
Defined by ANSI/IEEE Std. 519-1981
Distorting the waveform and changing its magnitude.
Tortech Pty Ltd
Total Transformer
Solutions
5. Three-phase metering units for solar installation
33KV Metering Unit
22 KV Metering Unit with 3 phase Current Transformers
22 KV Metering Unit 12 Core CT's
J.S Hansom Pty. Ltd.5
Tortech Pty Ltd
Total Transformer
6. Tortech Pty Ltd
Total Transformer
CT design under power grid harmonic conditions
The phase angle error affects the accuracy of the measurement when
harmonic powers are measured.
The magnetizing current is the cause of angle error.
The lower the ferromagnetic core permeability the larger becomes the
magnetizing current and the phase angle error.
6
7. Tortech Pty Ltd
Total Transformer
CT design under power grid harmonic conditions
Power frequencies Magnetic error
Higher frequencies Capacitive error
Increase the apparent permeability of the magnetic core
Decrease the number of turns in the ratio windings
To be Minimized
To be Minimized
7
8. CT design under power grid harmonic conditions
550kv Current Transformer for ECNSW
Cascade HV Magnetic Voltage Transformer
8
Tortech Pty Ltd
Total Transformer
Solutions
9. Effect Of Harmonics On Transformers:
Tortech Pty Ltd
Total Transformer
Harmonics and three phase transformers
9
10. Tortech Pty Ltd
Total Transformer
Harmonics and three phase transformers
Fluke 435 series II power quality and energy analyser
EEP Electrical Engineering Portal10
11. ANSI/IEEE standard 519-2014: Voltage harmonic distortion limits
Harmonics and three phase transformers
Bus voltage V at PCC Individual harmonic (%) Total Harmonic Distortion (%)
V ≤ 1kV 5 8
1 kV < V ≤ 69 kV 3 5
69 kV < V ≤ 161 kV 1.5 2.5
161 kV < V 1 1.5
Tortech Pty Ltd
Total Transformer11
12. Odd harmonics non-
multiple of 3
Odd harmonics
multiple of 3
Even harmonics
Order h Harmonic
voltage %
Order h Harmonic
voltage %
Order h Harmonic
voltage %
5 6 3 5 2 2
7 5 9 1.5 4 1
11 3.5 15 0.3 6 0.5
13 3 21 0.2 8 0.5
17 2 >21 0.2 10 0.5
19 1.5 12 0.2
23 1.5 >12 0.2
25 1.5
>25 0.2+1.3×(25/h)
NOTE: Total Harmonic Distortion (THD)=8%
Australia/New Zealand standard AS/NZS 61000-3-6 limits- Assessment of emission limits for distorting load in
MV and HV power systems
Harmonics and three phase transformers
12
Tortech Pty Ltd
Total Transformer
Solutions
13. IEC Standard 61000-3-6: Compatibility levels for individual harmonics voltages in low and medium voltage
networks in percent of fundamental voltage
Harmonics and three phase transformers
Odd harmonics non-multiple
of 3
Odd harmonics multiple
of 3
Even harmonics
Order h Harmonic
%
Order h Harmonic
voltage %
Order h Harmonic voltage
%
5 6 3 5 2 2
7 5 9 1.5 4 1
11 3.5 15 0.3 6 0.5
13 3 21 0.2 8 0.5
17≤h≤49 2.27×(17/h)-0.27 21<h≤45 0.2 10≤h≤50 0.25× (10/h)+0.25
NOTE: NOTE: Total Harmonic Distortion (THD)=8%
13
Tortech Pty Ltd
Total Transformer
14. EN 50160:2010 Voltage characteristics of electricity supplied by public electricity networks
Harmonics and three phase transformers
Odd harmonics non-
multiple of 3
Odd harmonics multiple
of 3
Even harmonics
Order h Harmonic
voltage %
Order h Harmonic
voltage %
Order h Harmonic
voltage %
5 6 3 5 2 2
7 5 9 1.5 4 1
11 3.5 15 0.5 6…24 0.5
13 3 21 0.5
17 2
19 1.5
23 1.5
25 1.5
NOTE: No values are given for harmonics of order higher than 25, as they
usually small, but largely unpredictable due to resonance effects.
14
Tortech Pty Ltd
Total Transformer
Solutions
16. Finite Element Analysis of Three-phase Transformers under
Harmonics
FEM has proven itself as an effective numerical method that
takes into account the geometry complexity, material
properties, saturation effects and non-linearities
A real three-phase isolation transformer is analyzed and
modelled in Ansys Electronic Desktop (AED)
Different tests were performed to obtain the initial results
and check the transformer characteristics.
Three-phase isolation transformer employed
for FEM simulations
Majid Malekpour, Michael Larkin, Ganesh Surendran, and Toan Phung, “Core Loss Studies using FEM of a Three Phase Isolation Transformer
under Harmonic Conditions”, the 2nd IEEE International Conference on Electrical Materials and Power Equipment (ICEMPE 2019), April 7th-
10th, 2019, Guangzhou, China.
16
Tortech Pty Ltd
Total Transformer
17. Finite Element Analysis of Three-phase Transformers under Harmonics
Tortech Pty Ltd
Total Transformer
Detailed flowchart of the proposed model in FEM
(2.5MVA, 80kVA, and 300VA three-phase isolation
transformers
17
18. Finite Element Analysis of Three-phase Transformers under Harmonics
Tortech Pty Ltd
Total Transformer
Magnetizing curve of the core material Core loss curves of the core material
3D modelling of the isolation transformer under mesh operation
18
19. Finite Element Analysis of Three-phase Transformers under Harmonics
Tortech Pty Ltd
Total Transformer19
20. Tortech Pty Ltd
Total Transformer
EXPERIMENTAL AND SIMULATION RESULTS
Core loss curves at different frequencies
20
21. Finite Element Analysis of Three-phase Transformers under Harmonics
Primary voltages obtained for an 80kVA three-phase isolation transformer
Secondary voltages obtained for an 80kVA three-phase isolation transformer21
22. Finite Element Analysis of Three-phase Transformers under Harmonics
Primary currents obtained for an 80kVA three-phase isolation transformer
Core loss obtained for an 80kVA three-phase isolation transformer22
23. Finite Element Analysis of Three-phase Transformers under Harmonics
Tortech Pty Ltd
Total Transformer
Eddy current and hysteresis losses obtained in FEM
23
Eddy current loss
Hysteresis loss
Eddy current loss
Hysteresis loss
24. Finite Element Analysis of Three-phase Transformers under Harmonics
The model in FEM requires validation
Experiments are carried out to evaluate the proposed
modelling approach.
A 3-phase, 300 VA, YD, 415/415 V, 50 Hz, isolation
transformer is fed through the AMETEK CSW55
programmable power supply
Current is measured through a current probe and sent to
computer via a National Instruments PCI 6024E data
acquisition board.
UNSW High Voltage Laboratory
24
AMETEK
CSW55
Transformer
Set up Inside
the Cage
Personal
Computer
Tortech Pty Ltd
Total Transformer
25. Finite Element Analysis of Three-phase Transformers under Harmonics
Tortech Pty Ltd
Total Transformer
The measured core loss under pure sinusoidal input voltage is 8.381 W and 7.2194 W for experiment and FEM, respectively.
The results show 13.86% difference between FEM and experiment which demonstrates the accuracy of the FEM model
Primary Current
25
26. Tortech Pty Ltd
Total Transformer
EXPERIMENTAL AND SIMULATION RESULTS
Case I:
Fundamental Frequency
100%
2nd Harmonic Component 8th Harmonic Component
0%0%
Core Loss (Experiment) = 8.381 W
Core Loss (FEM) = 7.2194 W
Primary Voltage Primary Current
26
27. Tortech Pty Ltd
Total Transformer
EXPERIMENTAL AND SIMULATION RESULTS
Case II:
Fundamental Frequency
100%
2nd Harmonic Component 8th Harmonic Component
2.5%10%
Core Loss (Experiment) = 8.405 W
Core Loss (FEM) = 7.2298 W
Primary Voltage Primary Current
27
28. Tortech Pty Ltd
Total Transformer
EXPERIMENTAL AND SIMULATION RESULTS
Case III:
Fundamental Frequency
100%
2nd Harmonic Component 8th Harmonic Component
10%10%
Core Loss (Experiment) = 9.28571 W
Core Loss (FEM) = 7.8962 W
Primary Voltage Primary Current
28
29. Tortech Pty Ltd
Total Transformer
EXPERIMENTAL AND SIMULATION RESULTS
Case IV: Highest percentage of each harmonic order defined by IEC 61000-3-6 Standard
Core Loss (Experiment) = 16.19 W
Core Loss (FEM) = … W
Primary Voltage Primary Current
29
30. Tortech Pty Ltd
Total Transformer
EXPERIMENTAL AND SIMULATION RESULTS
INCREASED LOSS PERCENTAGE BETWEEN CASE I AND OTHER CASES (%)
Experiment FEM
Case I - -
Case II 0.28 % 0.15 %
Case III 10.8 % 9.37 %
Case IV 94.78 % -
30
Case I:
Fundamental Frequency
100%
2nd Harmonic Component 8th Harmonic Component
0%0%
Case II: 100% 2.5%10%
Case III: 100% 10%10%
Case IV: Highest percentage of each harmonic order defined by IEC 61000-3-6 Standard
31. Tortech Pty Ltd
Total Transformer
K-Factor Transformers
As derived from ANSI/IEEE C57.110, a K-factor of 1.0 indicates a linear load (no harmonics). The higher the
K-factor, the greater the harmonic heating effects.
Transformers come in basic K-factors such as 4, 9,13, 20, 30, 40, and 50.
K-Factor = 1
34 𝑖ℎ×ℎ 2
1
34 𝑖ℎ
2
h is the harmonic number
31
32. Tortech Pty Ltd
Total Transformer
K-Factor Transformers
shield between the two windings
smaller conductor section size
larger overall conductors
larger neutral conductors
high quality magnetic steel core
thinner laminations
larger overall core size
enhanced cooling system
32
33. Tortech Pty Ltd
Total Transformer
Temperature rise calculation
2.5 MVA three-phase isolation transformer
33
34. Temperature rise calculation
Temperature Rise Test Without Enclosure
Cold
Circumstances
test data
Cold resistance 𝐑 𝟏(Ω) Temperature 𝛉 𝟎𝟏
HV 0.2343 LV 0.0002766 8.9 ℃
No-load test Heat resistance 𝐑 𝟐(Ω) Temperature 𝛉 𝟎𝟐 Core temperature 𝛉 𝟏
HV 0.2363 LV 0.0002916 9.2 ℃ 89.1 ℃
Coil temperature rise
∆𝑄 𝑒=
𝑅2
𝑅1
× (235 + 𝜃01)-(235+𝜃02)
HV 1.7 K LV 12.38 K
Load test data Heat resistance 𝐑 𝟐𝐥(Ω) Temperature 𝛉 𝟎𝟐𝐥 Core temperature 𝛉 𝟏𝐥
HV 0.31548 LV 0.000372 8.9 ℃ 74 ℃
Coil temperature rise
∆𝑄𝑐=
𝑅2𝑙
𝑅1
× (235 + 𝜃01)-(235+𝜃02𝑙)
HV 81.04 K LV 80.67 K
Results Coil temperature rise
∆𝐐 𝐜𝐭= ∆𝐐 𝐜 × 𝟏 +
∆𝐐 𝐞
∆𝐐 𝐜
𝟏.𝟐𝟓 𝟎.𝟖
Core temperature
𝐓 = 𝛉 𝟏 − 𝛉 𝟎𝟐
HV 81.56 K LV 86.82 K 79.90 K
34
Tortech Pty Ltd
Total Transformer
Solutions
35. Tortech Pty Ltd
Total Transformer
Temperature rise calculation
Temperature rise analysis for the 2.5MVA three-phase isolation transformer
based on the results obtained by FEM and open-air test set up
35
36. Tortech Pty Ltd
Total Transformer
Temperature rise calculation
Number of Doors:
Section Row Column
Total Amount
of Louvres
A0
Row (L)
(m)
A0
Column (H)
(m)
A0
Total
(m^2)
A1 Total
(m^2)
φ
= A1/A0
A0
Total
(m^2)
A1 Total
(m^2)
φ
= A1/A0
A0
Total
(m^2)
A1 Total
(m^2)
φ
= A1/A0
4
Per Door:
Bottom Section (Inlet) 9 6 54 0.88 0.22 0.1936 0.00702 0.036260331 0.1936 0.00702 0.036260331
Top Section (Outlet) 9 6 54 0.88 0.22 0.1936 0.00702 0.036260331 0.1936 0.00702 0.036260331
Total for All Four Doors 432 1.5488 0.05616 0.036260331 0.7744 0.02808 0.036260331 0.7744 0.02808 0.036260331
HV Side:
Bottom Left (Inlet) 12 4 48 1.18 0.136 0.16048 0.00624 0.03888335 0.16048 0.00624 0.03888335
Bottom Centre (Inlet) 12 8 96 1.18 0.304 0.35872 0.01248 0.034790366 0.35872 0.01248 0.034790366
Bottom Right (Inlet) 12 4 48 1.18 0.136 0.16048 0.00624 0.03888335 0.16048 0.00624 0.03888335
Top Left (Outlet) 20 4 80 1.98 0.136 0.26928 0.0104 0.038621509 0.26928 0.0104 0.038621509
Top Centre (Outlet) 6 8 48 0.58 0.304 0.17632 0.00624 0.0353902 0.17632 0.00624 0.0353902 Length
Top Right (Outlet) 20 4 80 1.98 0.136 0.26928 0.0104 0.038621509 0.26928 0.0104 0.038621509 Width
Middle Left (Outlet) 18 4 72 1.78 0.136 0.24208 0.00936 0.038664904 0.26928 0.0104 0.038621509 Height
Middle Centre (Outlet) 18 8 144 1.78 0.304 0.54112 0.01872 0.034594914 0.26928 0.0104 0.038621509 Thickness
Middle Right (Outlet) 18 4 72 1.78 0.136 0.24208 0.00936 0.038664904 0.26928 0.0104 0.038621509
Total for HV 400 1.39456 0.052 0.037287747 0.71488 0.02704 0.03782453 0.67968 0.02496 0.036723164
LV Side:
Bottom Left (Inlet) 12 4 48 1.18 0.136 0.16048 0.00624 0.03888335 0.16048 0.00624 0.03888335
Bottom Centre (Inlet) 12 8 96 1.18 0.304 0.35872 0.01248 0.034790366 0.35872 0.01248 0.034790366
Bottom Right (Inlet) 12 4 48 1.18 0.136 0.16048 0.00624 0.03888335 0.16048 0.00624 0.03888335
Top Left (Outlet) 19 4 76 1.88 0.136 0.25568 0.00988 0.038642053 0.25568 0.00988 0.038642053
Top Right (Outlet) 18 4 72 1.78 0.136 0.24208 0.00936 0.038664904 0.24208 0.00936 0.038664904
Middle Left (Outlet) 21 4 84 2.08 0.136 0.28288 0.01092 0.038602941 0.24208 0.00936 0.038664904
Middle Centre (Outlet) 26 8 208 2.58 0.304 0.78432 0.02704 0.034475724 0.24208 0.00936 0.038664904
Middle Right (Outlet) 16 4 64 1.58 0.136 0.21488 0.00832 0.038719285 0.24208 0.00936 0.038664904
Total for LV 340 1.17744 0.0442 0.037539068 0.49776 0.01924 0.038653166 0.67968 0.02496 0.036723164
Total for Enclosure 1172 4.1208 0.15236 0.036973403 1.98704 0.07436 0.037422498 2.13376 0.078 0.036555189
86.82
19
40
145.82
Outlet
21875
A0 = Total Ventilation Area
2500kVA Unit
Losses: (W)
1.6
2.55
0.003
Centre line from Inlet to Outlet: (m)
Surface Cooling Area:
Dimensions of Enclosure: (m)
A2
Louvre Size (m^2):
0.00013
Key:
Total Inlet
2.3
1.3
Signature:
A1 = Total Ventilation Open (Slot) Area
A2 = Area of Single Opening (Slot)
Transformer Temperature Rise Class F (155°C)
Enclosure Temperature Comment:
Ambient Temperature The total temperature rise is less than the
insulation material class.Total Temperature Rise
Temperature Rise Test
Temperature Rise Measured Results (°C) Insulation Class
Inlet and outlet louvre geometry consideration for the 2.5MVA three-
phase isolation transformer
36
37. Tortech Pty Ltd
Total Transformer
Temperature rise calculation
The designed Louvre size and geometry for
the 2.5MVA three-phase isolation
transformer
37
38. Tortech Pty Ltd
Total Transformer
Temperature rise calculation
The designed enclosure for the 2.5MVA three-phase isolation
transformer
38
39. Magnetically Controlled Reactor (MCR)
Oil-immersed and Dry type Magnetically Controlled
Reactors (MCRs)
Suppressing overvoltage
Mitigating secondary ARC current
Compensating the reactive power
Voltage stabilization
Mitigating voltage/current harmonics
It is a multifunctional device to increase the power quality by:
Tortech Pty Ltd
Total Transformer39
40. Magnetically Controlled Reactor (MCR)
Tortech Pty Ltd
Total Transformer
Schematic diagram of primary part of MSVC complete unitMagnetic structure of the MCR
40
41. Magnetically Controlled Reactor (MCR)
Tortech Pty Ltd
Total Transformer41
Magnetic Core
Thyristors
Enclosure
MCR
Control Panel
Epoxy cast
winding
As defined by ANSI/IEEE Std. 519-1981, harmonic components are represented by a periodic wave or quantity having a frequency that is an integral multiple of the fundamental frequency.
Harmonics superimpose themselves on the fundamentals waveform, distorting it and changing its magnitude.
Today’s power systems planning and maintenance requires monitoring and recording of harmonic currents and harmonic powers
Two errors are known to occur:
1) phase angle error
2) magnitude error
The instrument transformers with accuracy class 0.6 or better provide reasonably accurate measurements of current harmonics magnitudes, however the phase angle error may lead to unacceptable errors when the current transformers are used to measure active powers.
If such measurements are used to determine the power flow direction even high accuracy class CTs may yield unsatisfactory results.
such CT-caused errors may be misleading, indicating that a load absorbs harmonic power when in reality generates or vice versa.
For precise measurements of current harmonics, the current transformer must have both wide dynamic range and wideband for operation at frequencies higher than power frequencies.
At power frequencies, the magnetic error accounts for most of the transformer error while, at higher frequencies, the capacitive error is the predominant source of error.
The magnetic errors at the lower frequencies (power frequencies) must be minimized by greatly increasing the apparent permeability of the magnetic core, and the capacitive errors at higher frequencies must be minimized by keeping the number of turns in the ratio windings as low as possible.
During the last few decades, the use of solid-state power electronic devices, switch-mode power supplies, and equipment with non-linear current/voltage characteristics has drastically increased.
This has resulted in harmonic contamination of the power grid and accordingly distortion of the supply voltage waveforms that feed power equipment in the network.
The distortion of the supply voltage will result in undesirable power losses and temperature rise in transformers.
This will further result in insulation degradation, early catastrophic failure, and reduction of in-service transformer life expectancy.
Non-sinusoidal current generates extra losses and heating of transformer coils thus reducing efficiency and shortening the life expectancy of the transformer.
Coil losses increase with the higher harmonic frequencies due to higher eddy current loss in the conductors.
The “Triplen” harmonics cause installations to be double either the size or the number of neutral conductors.
Due to adverse impacts of harmonics to equipment or components on the network, international organisations publish various standards to regulate the level of harmonics in power system
It provides an approach to calculate transformer capacity when supplying distorted currents
In order to measure the required parameters for FEM simulations, a real three-phase isolation transformer is analyzed and different parameters such as the core geometry, size of windings, number of turns, and winding configuration are measured and modelled in Ansys Electronic Desktop (AED)
Formulating problems with FEM creates a system of algebraic equations. With this method, estimated values of unknowns can be obtained at distributed points over a domain. The method solves problems by subdividing the larger problem into smaller parts named as finite elements. Then, the equations modelling these finite elements are integrated into the larger equation system that models the problem as a whole.
The magnetizing (B-H) and core loss (B-P) curves are accurately applied and shown
In order to study the core loss under harmonic conditions, it is important to properly consider the effect of harmonics on simulations.
Each frequency component has its own B-P curve and hence the core loss is different. Increasing the harmonic order will increase the loss, and this should be accurately considered in FEM.
The power supply harmonics will not only distort the transformer voltage and currents but also will increase the core loss and the primary current amplitude.
FEM is particularly capable of dealing with complex geometries, and also yields stable and accurate solutions especially when explicit mathematical models are difficult to obtain or completely lacking.
There is good agreement between primary current signals obtained in FEM based on the proposed modelling technique and experiment
This section evaluates the core loss under harmonic situation. The primary side of the studied three phase isolation transformer is fed via an AMETEK CSW55 programmable power supply while the secondary side is kept open circuited. The AMETEK CSW55 programmable power supply makes it possible to consider different harmonics with different amplitude. The no-load loss is then measured by a FLUKE 39 power meter.
On the other hand, FEM is employed to obtain the no-load loss under different harmonic conditions. Different case studies have been considered.
Furthermore, to show the significance of the voltage harmonics on transformer losses, another study is carried out. The input voltage is formed based on the highest percentage of harmonic orders recommended by the IEC 61000-3-6
The K-factor rating is an index of the transformer's ability to withstand harmonic content while operating within the temperature limits of its insulating system.
The strategy is to calculate the K-factor for your load and then specify a transformer with a K-factor of an equal or higher value. In this way, the transformer can be sized to the load without derating.
May have a shield between the two windings to limit harmonic induction.
The basic conductor section size making up the transposed windings are made smaller to limit eddy currents.
The overall conductors may be made larger to reduce ohmic heating.
Neutral conductors may be made larger to limit the heating effects of triple-N harmonics.
The core is often made of better quality magnetic steel with lower hysteresis loss.
The core may have thinner laminations to reduce core eddy current losses.
The overall core size may be made larger to reduce operating flux density.
Cooling is also enhanced in K-factor transformer design.
The MCR-type SVC compensates the inductive and capacitive reactive power by using its magnetically-controlled reactor and capacitor compensation branches.
The capacitor compensation branch can be designed so that it can act like a filter to filter out different harmonic components while still compensating the reactive power.
GT-MSVC complete unit mainly consists of the magnetically controlled reactor branch and capacitor compensation (filter) branch connected in parallel.
The magnetically controlled reactor consists of MCR body, group valve and control part that is connected to the network bus through a breaker.
The capacitor compensation (FC) branch is composed of compensation (filter) capacitor, filter reactor, lightning arrester, fuse, discharge coil, protection and control panel etc. that is connected to the network bus through a breaker.