2014-03-30 12-06 pm.pdf
1/1.docx
Power Electronics
Contents
1.0 Rectifier using Diodes 3
1.1 Rectifier with filter output current direct 7
1.2 Applications 8
2.0 Schmatic circuits 11
2.1 Rectifire circuit 11
2.2 Output waveforms 12
2.3 Controlled rectifier 13
3.0 References 18
Figure 1: simple half-wave rectifier circuit composed of a single diode3
Figure 2: operation of a rectifier circuit for full-wave alternating current composed of two silicon diodes.4
Figure 3: Schematic represent different forms of the same full-wave bridge rectifier consists of four diodes.5
Figure 4: four-diode bridge rectifier6
Figure 5: linear direct current7
Figure 6: added to the filter resistance (R) or an inductance (L)8
Figure 7: 12 volt direct current (DC)9
Figure 8: current (DC) motor9
Rectifier using Diodes
The rectification of alternating current (AC) to convert it into direct current (DC). This rectification is one of the oldest technologies used in electronic circuits since early last century, even before the existence of the solid state semiconductor elements such as silicon diodes know today. Since the diodes allow the passage of electric current in one direction and prevent it in the opposite direction, have also been used for many years in the detection of high-frequency signals, such as broadcasters, to turn them into audible in radio receivers. At present several types of special construction diodes can perform functions other than simple correction or current detection when installed in electronic circuits. Operation of a common half wave rectifier diode To better understand how works a semiconductor diode, remember that the first alternating current (AC) flowing through the electrical circuit forming a sinusoid, which has positive polarity half cycle while the other half cycle has negative polarity. That is, when an alternating current flows through a closed circuit constantly changes its polarity many times as cycles per second or hertz frequency have. In the case of alternating current that comes into our homes can often be 50 or 60 cycles depending on the system adopted by each country. In Europe the frequency adopted is 50 cycles and 60 cycles in most of Latin (See table of frequency of the current country and the respective voltages).
Figure 1: simple half-wave rectifier circuit composed of a single diode
In the animation above it can see that in the process of rectifying the alternating current (AC) using a single diode, for a first negative half cycle the electrons will flow through the circuit through first diode and then the consumer or electric charge, represented by a resistance (R) . At that moment, at the ends of the resistance was able to detect a direct "pulsing" that responds to the current half cycle. In the next half cycle (this time positive), electrons change their direction of movement and cannot pass nor resistance, nor the semiconductor diode, because at that time the road will be blocked by the positive term.
Some devices could not work corrctly on A.C (Alternating current source) thats why we need to Convert A.C(Alternating current source) into D.C (Direct current source).
Some devices could not work corrctly on A.C (Alternating current source) thats why we need to Convert A.C(Alternating current source) into D.C (Direct current source).
Sesión de Laboratorio 3: Leyes de Kirchhoff, Circuitos RC y DiodosJavier García Molleja
Laboratory session in Physics II subject for September 2016-January 2017 semester in Yachay Tech University (Ecuador). Topic covered: electricity, electrical circuits, resistances, capacitances, diodes
Based on Bruna Regalado's work
Transformer Less Voltage Quadrupler Based DC-DC Converter with Coupled Induct...IJPEDS-IAES
In this paper a voltage quadrupler dc-dc converter with coupled inductor
and π filter is presented. The use of the coupled inductor reduces the high
leakage inductance which is present in a transformer enabled converter.
The output ripples in the converter is reduced by providing a π filter.
The interleaved voltage quadrupler is used in this system in order to boost the
output voltage. The voltage multiplier improves the output voltage gain.
The main advantage of this system is more voltage gain when compared with
the transformer eneabled circuit and the overall efficiency of the system is
improved. The circuit is simple to control. As a final point of this research,
the simulation and the hardware investigational results are presented to
demonstrate the effectiveness of this proposed converter.
A Comparative Study of Various AC-DC Converters for Low Voltage Energy Harves...paperpublications3
Abstract: Electromagnetic microscale and mesoscale power generators with low voltage outputs are now widely used as kinetic energy harvesters. The extrinsic vibrations on the generator can excite the internal oscillations between the proof mass magnet and the electrical damper coils. These oscillations produce a periodically varying magnetic flux in coil, inducing a corresponding AC output voltage. This output can be converted to dc and can be used to supply power to electronic loads. The conventional AC-DC converters for energy harvesting system with diode rectifiers suffer considerable voltage drop resulting increase in power loss of circuitry and complexity. As a remedy various bridgeless boost converters were designed and implemented. Standard H bridge converter with 4 switch or 2 switch, dual polarity boost converters, parallel combination of boost and buck-boost converter, integrated boost and buck-boost combination bridgeless rectifier are some of these. These circuits are studied, simulated and compared. The simulation models are drawn and simulated using MATLAB R2010a.
The presentation consists of the detailed explanation on the topic of Converters, specifically on the rectifiers, different types of rectifiers ( Half-wave, full-wave and bridge ) configuration. The advantages and disadvantages of rectifiers and their applications
I need a 7 pg research essay on the following Select a real o.docxeugeniadean34240
I need a 7 pg research essay on the following:
Select a real or hypothetical crisis, such as a natural disaster (hurricane, tornado, flooding, or earthquake), a catastrophic building failure, or an act of terrorism.
Discuss resource management based on ethical approaches used during crisis management.
Consider issues such as patient triage or current as well as incoming patients, supply, and personnel availability.
Discuss and develop an authoritative chain of command for crisis management.
Include such responsibilities as Incident Commander, Communications Officer, and other members of the chain of command for the incident.
Discuss the importance and implementation of community communication, involvement, and coordination.
Discuss the necessary policies for personnel management and safety.
Include provisions for lock-down status and family communication abilities.
Outline the steps for supply chain management, both for personnel and the supplies needed to provide care.
.
I need a 4-5 APA formatted paper with references that is clearly wri.docxeugeniadean34240
I need a 4-5 APA formatted paper with references that is clearly written and includes the following:
The attendance of an AA meeting. Describe the meeting's atmosphere, the participants and their appearances, details on the group discussion, engagement, timeframe, the pros and cons of the meeting, and other helpful information.
.
More Related Content
Similar to 2014-03-30 12-06 pm.pdf11.docxPower Ele.docx
Sesión de Laboratorio 3: Leyes de Kirchhoff, Circuitos RC y DiodosJavier García Molleja
Laboratory session in Physics II subject for September 2016-January 2017 semester in Yachay Tech University (Ecuador). Topic covered: electricity, electrical circuits, resistances, capacitances, diodes
Based on Bruna Regalado's work
Transformer Less Voltage Quadrupler Based DC-DC Converter with Coupled Induct...IJPEDS-IAES
In this paper a voltage quadrupler dc-dc converter with coupled inductor
and π filter is presented. The use of the coupled inductor reduces the high
leakage inductance which is present in a transformer enabled converter.
The output ripples in the converter is reduced by providing a π filter.
The interleaved voltage quadrupler is used in this system in order to boost the
output voltage. The voltage multiplier improves the output voltage gain.
The main advantage of this system is more voltage gain when compared with
the transformer eneabled circuit and the overall efficiency of the system is
improved. The circuit is simple to control. As a final point of this research,
the simulation and the hardware investigational results are presented to
demonstrate the effectiveness of this proposed converter.
A Comparative Study of Various AC-DC Converters for Low Voltage Energy Harves...paperpublications3
Abstract: Electromagnetic microscale and mesoscale power generators with low voltage outputs are now widely used as kinetic energy harvesters. The extrinsic vibrations on the generator can excite the internal oscillations between the proof mass magnet and the electrical damper coils. These oscillations produce a periodically varying magnetic flux in coil, inducing a corresponding AC output voltage. This output can be converted to dc and can be used to supply power to electronic loads. The conventional AC-DC converters for energy harvesting system with diode rectifiers suffer considerable voltage drop resulting increase in power loss of circuitry and complexity. As a remedy various bridgeless boost converters were designed and implemented. Standard H bridge converter with 4 switch or 2 switch, dual polarity boost converters, parallel combination of boost and buck-boost converter, integrated boost and buck-boost combination bridgeless rectifier are some of these. These circuits are studied, simulated and compared. The simulation models are drawn and simulated using MATLAB R2010a.
The presentation consists of the detailed explanation on the topic of Converters, specifically on the rectifiers, different types of rectifiers ( Half-wave, full-wave and bridge ) configuration. The advantages and disadvantages of rectifiers and their applications
I need a 7 pg research essay on the following Select a real o.docxeugeniadean34240
I need a 7 pg research essay on the following:
Select a real or hypothetical crisis, such as a natural disaster (hurricane, tornado, flooding, or earthquake), a catastrophic building failure, or an act of terrorism.
Discuss resource management based on ethical approaches used during crisis management.
Consider issues such as patient triage or current as well as incoming patients, supply, and personnel availability.
Discuss and develop an authoritative chain of command for crisis management.
Include such responsibilities as Incident Commander, Communications Officer, and other members of the chain of command for the incident.
Discuss the importance and implementation of community communication, involvement, and coordination.
Discuss the necessary policies for personnel management and safety.
Include provisions for lock-down status and family communication abilities.
Outline the steps for supply chain management, both for personnel and the supplies needed to provide care.
.
I need a 4-5 APA formatted paper with references that is clearly wri.docxeugeniadean34240
I need a 4-5 APA formatted paper with references that is clearly written and includes the following:
The attendance of an AA meeting. Describe the meeting's atmosphere, the participants and their appearances, details on the group discussion, engagement, timeframe, the pros and cons of the meeting, and other helpful information.
.
I need a 3 page research paper on Title Addictive being youn.docxeugeniadean34240
I need a 3 page research paper on
Title:
Addictive being young and older on Social Media, why activities outdoors can prevent addiction
In the attached zip file, I have provided 10 journals that you need to use for this research paper.
In the word doc, I have shared the topic and sub-topics that you have to use. And it also has guidelines from the teacher for this paper.
Due on Saturday, 13th March 4PM PST
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I need a 3 page double-spaced 12-point paper on Immunotherapy. the i.docxeugeniadean34240
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I need a 200-word paper that answers the following questions:D.docxeugeniadean34240
I need a 200-word paper that answers the following questions:
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I need a 1 page professional bio. My cover letter and resume i.docxeugeniadean34240
I need a 1 page professional bio.
My cover letter and resume is attached.
As an experienced and motivated professional with exceptional leadership and interpersonal abilities, I am prepared to significantly contribute to your organization’s goals in this role.
My background lies in workforce and economic development, managing operations, teams, conflict resolution, and processes to propel revenue increases while realizing enhanced corporate success and productivity. From establishing and implementing visionary business strategies to driving employees to achieve peak performance levels, I excel at directing strategic enhancements to outperform open objectives while communicating openly and effectively with staff and management teams.
Highlights of my experience include the following:
Ø Excelling as the Manager of the workforce development team with the Shelby County Alternative Schools for the past 10 years, federal grant management, identifying employment opportunities for youth and adult offenders, educating and supporting clients through vocational training initiatives, evaluating client work interests and aptitudes, and connecting clients with eligible and appropriate employment programs.
Ø Assisting program participants in identifying anger, recognizing aggressive behavior triggers, and learning tension and anger management techniques.
Ø Coaching and mentoring staff to ensure outstanding job performances and maximum program effectiveness. (virtual and face-to-face)
Ø Scheduling and coordinating opportunities for training, recreation, and leisure activities tailored to participants ‘preferences and age-appropriateness
Ø Encouraging an atmosphere supportive of constructive feedback and performance evaluation/improvement
Ø Adept at establishing goals and driving achievement through education, training, communication, and resource utilization
Ø Maintaining detailed records and reports to document participant progress and status
Ø Demonstrating solid time management, interpersonal, and organizational skills, as well as Microsoft Office proficiency.
Ø Compiling and analyzing client data obtained through records, tests, interviews, and other professional sources, determining clients’ suitability for various job opportunities and vocational training programs
Ø Facilitating and leading both individual and group orientation sessions and educating participants on requirements for participation in agency- sponsored programs
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My proven dedication to optimizing workforce development and employment success through my expert knowledge of learning, development, and conflict resolution strategies will contribute immensely to the success of your-team.
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I need 100 words response for this two discussion forum1 discu.docxeugeniadean34240
I need 100 words response for this two discussion forum
1 discussion
Colin Kaepernick comes to mind as I speak of racial differences, principles and morals. Colin Kaepernick, when he chose to go beyond the usual practice, effectively gave up his dream. Colin Kaepernick, the American football player who started the National Anthem "take knee" campaign against racial violence against African American and other races. Business ethics is the study of what constitutes right or wrong, good or bad human conduct in a business environment. The introduction of universal ethical principles to particular practical problems in the modern environment, such as dishonesty in ads, bullying, etc., is intended to assess what is "valid" behavior; i.e. what is considered appropriate or "right" conduct in line with universal ethical values (Christie et al, 2003).
I served with a social-service organization in 2013. Within this unique setting, I have been forced to interact alongside a variety of communities and faiths. Each of the SNAP entitlements (Food stamps) is dependent on family revenue and wealth. There was, however, a misconception and theory circulated inside the department that African American culture is lazy and that many of them do not want to function and want to rely on the government for assistance. I know that the theory and the story arose from the deep-rooted fear of the Slavery. Under which racial violence persists and so other groups are still competing and killing each other.
At another agency I worked for I worked with youth directly in a foster care setting. I am African American, and the rest of the children I represent are Hispanic / Latino. I note that when I'm out in the city with my Hispanic / Latino clientele, I typically get a number of stares from various cultures. One of my four-year-old children sometimes holds a temper tantrum to get what she needs from her mother. She decided to have one of these tantrums with me when we were in the grocery shop. I dismissed her actions, and there was a Hispanic lady who came up to me with a really unpleasant attitude, telling me to know what I was doing to the girl. I dismissed her and proceeded to focus on the actions of my client. I assume that she just got embroiled in this scenario because I mistreated this Hispanic child in her opinion, even though I gave her my badge for work. Anything I did with the child was in compliance with the Agency's rules and practices, even when I was being confronted by a consumer in the shop. It's really difficult to deal with babies, youth and even the elderly, so you also have to make sure that you perform it according to policies and procedures. Mandatory ethics was enforced to safeguard the employees who work for the specific organization and even the clients. Professionals are required to recognize and live by their Code of Ethics. Practitioners will need to demonstrate awareness regarding the adaptation of their codes to different cultures (Weber 20004).
I need 200 words response for each discussion post.Guided Respon.docxeugeniadean34240
I need 200 words response for each discussion post.
Guided Response: Respond to at least two of your classmates’ postings. Support your initial and subsequent posts by citing at least two scholarly and peer-reviewed sources in addition to the course text. The Scholarly, Peer-Reviewed, and Other Credible Sources (Links to an external site.) table offers additional guidance on appropriate source types.
Forum 1)One psychosocial issue that could cause a serious issue in the school setting to me would be Bullying. Bullying can scare a person’s ability to feel be ant to bully and be mean to someone because they may act different or look different to them, beautiful, safe, and secure about who they are, and be lasting ongoing issue that will last forever by making them feel insecure, and not wanted along while feeling like no one cares about them. Bullying is a form of abuse, aggressiveness, coercion, force. There are other things that bullies do to feel like they are important or better than everyone else, like be dominated, intimidating, or threatening. “Bullying in schools, particularly bias-based bullying, is an important issue for many reasons, but chief among them include evidence that victims being bullied experience both short and long term consequences, including poor school performance, depression, and increased health problems” (Martin, M. E. (2018).
I believe that the services of all three would be required because the bully would be evaluated three different times on his behavior and other things that no one may know about. Each of them has their own specialty that would fit working with the bully and being able to determine what is the issue or problem that makes the bully act out of character the way he or she does.
“An analysis of this phenomenon in schools, according to different authors [1,7.8, reveals that children involved in bullying behavior can play different roles; (a) aggressors/intimidators; (b) victim; (c) aggressors who are also victims and (d) passive observers. These observers are neither directly involved as aggressors nor as victims. As such, they can play a number of different roles: they can defend the victims, thus reducing this type of behavior; they can support the aggressors, actively reinforcing intimidation; children who merely observe are neutral or indifferent”. (www.ncbi.nim.nih.gov) (Links to an external site.) . There should something put into place that will stop individuals with aggressive behavior to stop bullying other individuals who just want to be themselves and live their lives. It leads to most children feeling depressed and wanting to end their lives because of it, and it happens in our society today children ending their lives because they are being targeted by bullies. Rules should also be put into place for the bullies to let them know what will happen if they continue to bully others.
REFERENCES:
Martin, M. E. (2018). Introduction to human services: Through the eyes of practice settings .
I need 3 pages discussion for an intersection (Attached image).docxeugeniadean34240
I need 3 pages discussion for an intersection (Attached image)
North Harbor Drive and Harbor Island Drive intersection, San Diego CA 92111 US
Please address the following:
a. Right of Way Issues
b. Utility Relocation
c. Air Quality Conformity
d. Title VI Considerations
e. Visual / Landscape Considerations
f. Required Permits
g. Stormwater Management
h. Cultural Resources
i. Risk Management Plan
j. Transportation Management Plan (TMP)
k. Transit Services
If you think any other better ideas, please address them as well.
University Level
Please no plagiarism
I also attached an example, you can follow it to get ideas to write about
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I need 1page write up on Hypothesis & Methods Proposal,Due on .docxeugeniadean34240
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Due on 3rd Feb 7PM PST
Please see attached doc for details on title, notes and questions to be answered.
Please cite everything, You might need the previous APA paper (attached image), but not sure. so please review
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The work has to be authentic and original (not copied), with the references stated where its used on the paper and at the end
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I need 120 words for each question. Please ensure to post individual.docxeugeniadean34240
I need 120 words for each question. Please ensure to post individual reference with each question
Unit 1
Q 1;
Identify two organizational structures used in health care. What are the central characteristics of each? To what extent is bureaucracy necessary in health care organizations? Explain.
Q 2;
How does a doctorally prepared nurse work across and between levels of an organization? What are the challenges and/or rewards to be gained? Does one outweigh the other?
Resources
Delmatoff, J., & Lazarus, I. R. (2014). The most effective leadership style for the new landscape of healthcare.
Journal of Healthcare Management, 59
(4), 245-249. URL:
https://lopes.idm.oclc.org/login?url=http://search.ebscohost.com.lopes.idm.oclc.org/login.aspx?direct=true&db=a9h&AN=97206195&site=ehost-live&scope=site
Arbab Kash, B., Spaulding, A., Johnson, C. E., & Gamm, L. (2014). Success factors for strategic change initiatives: A qualitative study of healthcare administrators' perspectives.
Journal of Healthcare Management, 59
(1), 65-81. URL:
https://lopes.idm.oclc.org/login?url=http://search.ebscohost.com.lopes.idm.oclc.org/login.aspx?direct=true&db=a9h&AN=94059299&site=ehost-live&scope=site
Kritsonis, A. (2004/2005). Comparison of change theories.
International Journal of Scholarly Academic Intellectual Diversity, 8
(1) 1-7. URL:
http://qiroadmap.org/?wpfb_dl=12
Suter, E., Goldman, J., Martimianakis, T., Chatalalsingh, C., Dematteo, D. J., & Reeves, S. (2013). The use of systems and organizational theories in the interprofessional field: Findings from a scoping review.
Journal of Interprofessional Care, 27
(1), 57-64. doi:10.3109/13561820.2012.739670 URL:
https://lopes.idm.oclc.org/login?url=http://search.ebscohost.com.lopes.idm.oclc.org/login.aspx?direct=true&db=a9h&AN=84423842&site=ehost-live&scope=site
Narayana, E. A. (1992). Bureaucratization of non-governmental organizations: An analysis of employees' perceptions and attitudes.
Public Administration and Development, 12
(2), 123-137. URL:
https://lopes.idm.oclc.org/login?url=http://search.proquest.com.lopes.idm.oclc.org/docview/194674953?accountid=7374
Klemsdal, L. (2013). From bureaucracy to learning organization: Critical minimum specification design as space for sensemaking.
Systemic Practice & Action Research
,
26
(1), 39-52. doi:10.1007/s11213-012-9267-3 URL:
https://lopes.idm.oclc.org/login?url=http://search.ebscohost.com/login.aspx?direct=true&db=bth&AN=84739308&site=ehost-live&scope=site
Unit 2
Q 1:
What are three payment structures used in the health care industry across the care continuum? How are they similar? How are they different? Is there a single problem that transverses all three of the identified payment structures? Explain.
Q 2:
Identify a significant problem with one of the three payment structures used in the health care industry across the care continuum (from DQ 1) and propose a solution from one of the other two payment structures.
Resources
.
I need 10-12 slides Presentation with detailed speaker notes. Instru.docxeugeniadean34240
I need 10-12 slides Presentation with detailed speaker notes. Instruction is given below. It is a Religion Class. No Plagiarism Please. Due in 24 hours.
Wk 3 - Christianity Presentation
Create
a 10- to 12-slide presentation comparing
2
of the following branches of Christianity:
Catholic
Orthodox
Protestant
Include
a brief history of the 2 religious traditions and a comparison of their approaches to the Bible. Some concepts to include are:
Examples of art
Central symbols of the faith
Rituals and core beliefs
Ethics role in the faith
You might consider visiting one or more of these churches in person or exploring church websites to add to your own experiences.
.
I N N O V A T I O N N E T W O R K , I N C . www.innone.docxeugeniadean34240
I N N O V A T I O N N E T W O R K , I N C .
www.innonet.org • [email protected]
L o g i c M o d e l W o r k b o o k
I N N O V A T I O N N E T W O R K , I N C .
www.innonet.org • [email protected]
L o g i c M o d e l W o r k b o o k
T a b l e o f C o n t e n t s
P a g e
Introduction - How to Use this Workbook .....................................................................2
Before You Begin .................................................................................................................3
Developing a Logic Model .................................................................................................4
Purposes of a Logic Model ............................................................................................... 5
The Logic Model’s Role in Evaluation ............................................................................ 6
Logic Model Components – Step by Step ....................................................................... 6
Problem Statement: What problem does your program address? ......................... 6
Goal: What is the overall purpose of your program? .............................................. 7
Rationale and Assumptions: What are some implicit underlying dynamics? ....8
Resources: What do you have to work with? ......................................................... 9
Activities: What will you do with your resources? ................................................ 11
Outputs: What are the tangible products of your activities? ................................. 13
Outcomes: What changes do you expect to occur as a result of your work?.......... 14
Outcomes Chain ....................................................................................... 16
Outcomes vs. Outputs ............................................................................. 17
Logic Model Review ...........................................................................................................18
Appendix A: Logic Model Template
Appendix B: Worksheet: Developing an Outcomes Chain
Logic Model Workbook
Page 2
I N N O V A T I O N N E T W O R K , I N C .
www.innonet.org • [email protected]
I n t r o d u c t i o n - H o w t o U s e t h i s W o r k b o o k
Welcome to Innovation Network’s Logic Model Workbook. A logic model is a commonly-used
tool to clarify and depict a program within an organization. You may have heard it described as
a logical framework, theory of change, or program matrix—but the purpose is usually the same:
to graphically depict your program, initiative, project or even the sum total of all of your
organization’s work. It also serves as a
foundation for program planning and
evaluation.
This workbook is a do-it-yourself guide to
the concepts and use of the logic model. It
describes the steps necessary for you to
create logic models fo.
I like to tie my learning to Biblical Principles. On Virtuous Le.docxeugeniadean34240
I like to tie my learning to Biblical Principles. On Virtuous Leadership, I think about what leader in the Bible do I know that stands out as a virtuous leader. Although there are many, one that stands out to me is Nehemiah. Nehemiah's brother and others said that they had been to Jerusalem and the Wall has been broken down, and the gates were burned. Nehemiah listened and took this news personally as if he was the wounded party. In other words, it broke his heart to hear this news.
He then took personal responsibility, prayed, and asked God to forgive him and his people for not obeying his commands. Then he took personal action, and at great danger to himself, he appeared before the King sad - remember that no King wants a sad cupbearer. When the King saw how sad Nehemiah was, he asked him why, and Nehemiah explained the state of his city walls and asked permission to go and fix them. He went and fixed the walls. He got involved in the work as a servant leader and getting the people what they needed. They had a city again with walls and a gate, and most importantly, they had protection!
We can see in this story that a servant leader is someone who takes personal responsibility for what has gone wrong and sets out to fix it, but not only does he/she fix the problem, the servant leader gets involved in the work and works alongside his workers to get the job done right. By doing so, the servant leader demonstrates his care for his workers and organization.
Share a story of a servant leader either in the Bible or someone you know.
.
I just want one paragraph.!!C.W.Mills described ‘sociological im.docxeugeniadean34240
I just want one paragraph.!!
C.W.Mills described ‘sociological imagination’ as an ability to understand “the intersection of one's own biography and other biographies with history and the present social structure you find yourself and others in.” In short, it is the ability to understand the private in public terms. Essentially, Mills is describing an ability to discern patterns in social events and view personal experiences in light of those patterns. To highlight that, he uses two terms – “the personal troubles of milieu” and “the public issues of social structure.” ‘Troubles’ happen to us as individuals, and are a private matter of individual choices and biography. ‘Issues’ are public matters that transcend the individual, and have to do with societal structures and processes.
Here is the Question!!!
1- For this discussion, I want you to select one of the following health/medical issues, and offer a thoughtful reflection on it as both a hypothetical ‘personal trouble’ and a ‘public issue.’
- ADHD; obesity; eating disorder; infertility; Alzheimer’s disease; COVID.
.
i just need serious help answering the question. I have answered mos.docxeugeniadean34240
i just need serious help answering the question. I have answered most of them but the following posted questions are giving me problem.
# 1.1
(1 pts.) In the textbook case, what information led Dr. Tobin to conclude that Shaun Boyden's sexual attraction to children was not a passing fancy? '
A) the fact that he reported having the urges since adolescence
B) the fact that his wife was unaware of his problem
C) the fact that he was never caught in the past
D) the fact that he had a relatively normal sexual development
# 1.2
(1 pts.) Charlie has opted to have psychosurgery performed in order to change his pedophilic patterns. Which of the following procedures will Charlie have done?
A) prefrontal lobotomy
B) hypothalamotomy
C) castration
D) vasectomy
# 1.3
(1 pts.) Dr. Walters is instructing Harry to imagine that he has just "flashed" his genitals at an unsuspecting woman on the street. After the woman responds in horror, Harry is to imagine that all of his closest friends jump out of a nearby alley and start laughing at him. Dr. Walters is using the technique known as
A) systematic desensitization.
B) cognitive restructuring.
C) covert conditioning.
D) behavior modification.
# 1.4
(1 pts.) Who is most likely to be the target of a frotteurist's desires?
A) a person from work
B) a life-long friend
C) a shopper at the mall
D) a close relative
# 1.9
(1 pts.) Based on the information presented in the textbook case, Shaun Boyden might be considered a ______ since he had a normal history of sexual development and interests.
A) child rapist
B) preference molester
C) situational molester
D) generalized molester
# 1.12
(1 pts.) Joe becomes sexually aroused when he views sexually explicit photographs. He also gets really turned on when his lover undresses in front of him. Joe's behavior might be described as
A) fetishistic.
B) frotteuristic.
C) voyeuristic.
D) normal.
# 1.21
(1 pts.) John gets nauseous when he thinks about having sexual intercourse and he actively avoids the sexual advances of others. John might be diagnosed as having
A) male erectile disorder.
B) sexual aversion disorder.
C) dyspareunia.
D) inhibited male orgasm disorder.
# 1.27
(1 pts.) Five-year-old Timmy has older sisters who dress him up occasionally and call him "Timbelina" since they really wanted a little sister instead of a little brother. If this pattern continues it is possible that Tim might develop
A) sexual masochism.
B) sexual sadism.
C) pedophilia.
D) transvestic fetishism.
# 1.29
(1 pts.) Carol is extremely interested in sex but does not experience the vaginal changes that ordinarily precede sexual intercourse. Carol may have
A) sexual aversion disorder.
B) hypoactive sexual desire disorder.
C) inhibited female orgasm disorder.
D) female sexual arousal disorder.
# 1.32
(1 pts.) John is in a p.
I Headnotes and indexes are copyrighted and may not be duplica.docxeugeniadean34240
I Headnotes and indexes are copyrighted and may not be duplicated by photocopying, printing.
I or other means without the express permission of the publishers. 1 -800-351-0917
43 Fla. L. Weekly S512 SUPREME COURT OF FLORIDA
Committee later submitted a revised proposal in response to comments. While we
generally approve the Committee's revisions, the revised proposal would have allowed
twenty days[ ratherthan ten, to serve a reply brief. In order to maintain consistency with
otherprovisions in rule 9.146(g)(3)(B), we haverevised the Committee's proposal such
that parties are allowed twenty days to respond after the last initial brief, and ten days
to respond after the last answer brief.
3Wehave revised the Committee's proposal to refer specifically to requirements for
electronic service in Rule ofJudicial Administration 2.516(b).
"See CoastalDev. ofN. Fla.,Inc. v. City ofJacksonville Beach, 788 So. 2d 204,205
footnotes.
(a) Florida Supreme Court.
(111887-present: Fenelonv. State. 594 So. 2d 292 (Fla. 1992).
{211846-1886: Livingston v. L 'Engle, 22 Fla. 427 (1886).
J ±' C-fl&LL/fl 1
n.3(Fla.20CII); Fla. Power &Light Co. v.CityofDania,76l So.2d 1089,1094 (Fla.
2000) ("No statewide criterion exists at this time."); see also Broward Cty. v. G.B. V.
Intern., Ltd.
Anstead,J.)
, 787 So. 2d 838, 849-53 (Fla. 2001) (Pariente, J., dissenting, joined by
(LEWIS, J., concurring in part and dissenting in part.) I dissent
because there is no need to amend the rule with regard to joinder on
appeal. This amendment is likely to generate more confusion than
clarity. I concur with the remainder ofthe amendments.
! * * *
I ■
! ..■■■■
Rules of Appellate Procedure—Amendment—Uniform Citation
System
IN RE: AMENDMENTS TO FLORIDA RULE OF APPELLATE PROCEDURE
9.800. Supreme Court of Florida. Case No. SC17-999. October 25,2018. Original
Proceeding—Florida Rules of Appellate Procedure. Counsel: Courtney Rebecca
Brewer, Ch lir, Appellate CourtRules Committee, Tallahassee, Kristin A. Norse, Past
Chair, App sllate Court Rules Committee, Tampa; and Joshua E. Doyle, Executive
Director, and Heather Savage Telfer, Staff Liaison, The Florida Bar, Tallahassee, for
Petitioner.
(PER CUjRIAM.) This matter is before the Court for consideration of
proposed, amendments to Florida Rule ofAppellate Procedure 9.800
(Uniforn
Fla. Cons t.
TheFlorida Bar's Appellate CourtRules Committee (Committee)
proposes
uniform
proposal
Citation System). We havejurisdiction. See art. V, § 2(a),
amendments to rule 9.800 to substantially update the
citation formats provided in that rule. The Committee's
to amend the rule was first presented to the Court in the
Commirt 5e' s regular-cycle report ofproposed rule amendments in In
re Amendments to the Florida Rules ofAppellate Procedure—2017
Regular-Cycle Report, No. SC17-152 (Fla. report filed Jan. 31,
2017).' The Court, on its own motion, entered an order directing that
the proposed amendments to rule 9.800 be .
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http://sandymillin.wordpress.com/iateflwebinar2024
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Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
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2014-03-30 12-06 pm.pdf11.docxPower Ele.docx
1. 2014-03-30 12-06 pm.pdf
1/1.docx
Power Electronics
Contents
1.0 Rectifier using Diodes 3
1.1 Rectifier with filter output current direct 7
1.2 Applications 8
2.0 Schmatic circuits 11
2.1 Rectifire circuit 11
2.2 Output waveforms 12
2.3 Controlled rectifier 13
3.0 References 18
Figure 1: simple half-wave rectifier circuit composed of a single
diode3
Figure 2: operation of a rectifier circuit for full-wave
alternating current composed of two silicon diodes.4
Figure 3: Schematic represent different forms of the same full-
wave bridge rectifier consists of four diodes.5
Figure 4: four-diode bridge rectifier6
2. Figure 5: linear direct current7
Figure 6: added to the filter resistance (R) or an inductance (L)8
Figure 7: 12 volt direct current (DC)9
Figure 8: current (DC) motor9
Rectifier using Diodes
The rectification of alternating current (AC) to convert it
into direct current (DC). This rectification is one of the oldest
technologies used in electronic circuits since early last century,
even before the existence of the solid state semiconductor
elements such as silicon diodes know today. Since the diodes
allow the passage of electric current in one direction and
prevent it in the opposite direction, have also been used for
many years in the detection of high-frequency signals, such as
broadcasters, to turn them into audible in radio receivers. At
present several types of special construction diodes can perform
functions other than simple correction or current detection when
installed in electronic circuits. Operation of a common half
wave rectifier diode To better understand how works
a semiconductor diode, remember that the first alternating
current (AC) flowing through the electrical circuit forming a
sinusoid, which has positive polarity half cycle while the other
half cycle has negative polarity. That is, when an alternating
current flows through a closed circuit constantly changes its
polarity many times as cycles per second or hertz frequency
have. In the case of alternating current that comes into our
homes can often be 50 or 60 cycles depending on the system
adopted by each country. In Europe the frequency adopted is 50
cycles and 60 cycles in most of Latin (See table of frequency of
the current country and the respective voltages).
Figure 1: simple half-wave rectifier circuit composed of a single
diode
In the animation above it can see that in the process of
rectifying the alternating current (AC) using a single diode, for
a first negative half cycle the electrons will flow through the
circuit through first diode and then the consumer or electric
3. charge, represented by a resistance (R) . At that moment, at the
ends of the resistance was able to detect a direct "pulsing" that
responds to the current half cycle. In the next half cycle (this
time positive), electrons change their direction of movement
and cannot pass nor resistance, nor the semiconductor diode,
because at that time the road will be blocked by the positive
terminal of the diode and no movement of current through the
circuit. Then and during the negative half cycle following again
the diode returns to allow the passage of electrons, to lock it
again to change the direction of current flow and so on while
you carry on giving power to the diode. therefore during each
negative half cycle of a source of alternating current
(AC) connected to a diode polarity registers fixed to the ends of
a load connected to the output circuit of the diode itself, while
during the following positive half cycle does not appear polarity
whatsoever due to blocking diode that provides the flow of
electrons in reverse itself. Thus, consumer via pulsed current
will flow, since in this case the diode acts as a rectifier for half-
wave alternating current. Operation of the full wave rectifier
diodes When an electric circuit or electronic requires a direct
current that non-pulsating, but much more linear than that
allowed a simple half-wave rectifier, it is possible to combine
from two to four rectifier diodes such that the resultant is a
direct current (DC) with less residual oscillations.
Figure 2: operation of a rectifier circuit for full-wave
alternating current composed of two silicon diodes.
The most usual for a rectifier bridge of "full-wave" structure is
composed of four diodes connected conveniently. However, in
some cases, a similar effect is obtained only by connecting two
diodes, using as a supply source of alternating current (AC) a
transformer with a center tap on the secondary winding. That
allows to feed equally diodes each with its symmetry in counter
phase which enables the
Winding midpoint is always the negative while the positive
changes at their ends each half cycle of alternating current
4. frequency applied to the circuit. However, the output of the
rectifier circuit is obtained one direct current (DC) full wave.
However, most of the electrical or electronic circuits operating
with direct current (DC), use full-wave rectifiers consisting of
four diodes. Following are three outline shapes are illustrated in
a diagram the connection of the four diodes for full-wave
rectifier.
Figure 3: Schematic represent different forms of the same full-
wave bridge rectifier consists of four diodes.
A four-diode bridge rectifier works in the following way: as
shown in the part (A) for illustration, during the first negative
half cycle (-) of the power provided by the AC power supply
(AC) connected to bridge rectifier of electrons through the first
diode (1) , then the consumer (R) and then the diode (2)in order
to complete the flow of the current of electrons corresponding
to one half of the bridge rectifier circuit.
Figure 4: four-diode bridge rectifier
A four-diode bridge rectifier works in the following way: as
shown in the part (A) for illustration, during the first negative
half cycle (-) of the power provided by the AC power supply
(AC) connected to bridge rectifier of electrons through the first
diode (1) , then the consumer (R) and then the diode (2)in order
to complete the flow of the current of electrons corresponding
to one half of the bridge rectifier circuit.
For clarification, the arrival of the electrons on their way to the
connection point (a), cannot pass through the diode (4) because,
according to the placement of these cases within the circuit
block or impede the movement of electrons in that sense. Once
the electrons continue their journey, arriving at the connection
point (b), cannot pass through the diode (4), because the
electron current never flows toward his own encounter (similar
to what happens with the flow of water in a river), but always
moving toward the opposite pole of the power supply that
provides electricity, that is, the positive terminal of the
5. alternating current (AC) in this case. In Part (B) of the
illustration we see that the alternate current changes polarity
and hence the direction of flow of electrons. At this time,
electrons pass through the first diode (3), then pass through the
consumer (R) and finally, the diode (4) to return to the power
source and complete the circuit. Similar to what happened in the
previous cycle, now the diode (1) is responsible for block him
electrons so that they can direct towards the consumer (R) ,
while the diode (2) cannot pass through electrons, because they
cannot go at their own game, as in the previous half
cycle.Rectifier with filter output current direct
If want a rectifier device full wave give a possible as linear
direct current, we can place a filter composed of one or two
electrolytic capacitors polarized, such as (C 1 ) and (C 2 )
shown in the illustrations below, connected to the output circuit
of direct current (DC) and rectified.
Figure 5: linear direct current
Besides these capacitors should be added to the filter resistance
(R) or an inductance (L) connected between the two capacitors.
The filter function is to compensate for variations or residual
deformations that may be left remaining in the rectified current.
To do this during the negative half cycle and the capacitors are
charged during the positive half cycle next downloaded to fill
gaps without charge created between a ridge and the other
corresponding to the average rectified current waves.
Figure 6: added to the filter resistance (R) or an inductance (L)
However, some computers and electronic devices (especially the
sound, for example) require a direct current or rectified as pure
as linear as possible, so to get this result will need to place a
transistor below the filter, stabilizer function.Applications
Figure below show one full wave rectifier device used is shown
on a computer that operates on 12 volt direct current (DC),
connecting to a home making alternating current (AC) 220 volt.
On the left side of this device you can see a transformer
6. responsible for transforming or reduce the 220 volt input 12
volt output AC also. In the center it can see a bridge rectifier,
which converts the 12 volt alternating current (AC) into 12 volt
direct current (DC). To the right of the two electrolytic
capacitors and resistors which make filter function are
observed. The other strength is also visible, circuit is used to
reduce the voltage of the LED (at the bottom of photo)
employee as a witness or pilot light to indicate that the
computer is connected to AC power on your home network,
even when it is not in use.
Figure 7: 12 volt direct current (DC)
It is not always necessary to have a filter to use an alternating
current rectified. For example, in this photo it can see an only
made four separate diodes, which provide direct current (DC) to
a small bridge rectifier electric motor coupled to a fan
hairdryer. The black wires corresponding to the input
alternating current (AC) feeding the rectifier bridge. The
positive pole [with the sign (+) in red] and negative [with the
sign (-) in blue] indicate the output polarity of the direct current
and rectified by the bridge. In this case the positive and
negative terminals are connected directly to the input terminals
of the direct current (DC) motor, both located on the back
cover. As can be seen, in this case we have omitted the use of
filter as not being necessary for the engine to run.
Figure 8: current (DC) motor
Devices with different silicon diode bridges based rectifiers.
Alternately to make it directly. To the left is a laptop charger
that appears. Also allows us to continue working with it when
the batteries are always exhausted. They stay connected to the
network from the household AC outlet. In the center as shown
.Adapter used to energize a signal converter DTT (Digital
Television. On the right you can see a mobile phone charger.
7. The full-wave rectifiers have a wide use in different types of
devices such as adapters using different electronic equipment,
as well as battery chargers that use mobile phones, digital
cameras, mp3 players, computers laptops and many other more
appliances and electronic devices that operate with direct
current. Thus a bridge rectifier enables any device or equipment
direct current (DC) can connect to the network of alternating
current (AC) for domestic use thus being able, or otherwise
charge their batteries.
Schmatic circuitsRectifire circuit
The schematic figure above is using Pspice software.
· First circuit for single diode rectifier.
· Second circuit with adding inductive load “L” in series with
resistance.
· 3rd circuit with adding freewheeling diode in parallel with
load. Output waveforms
Yellow is output wave form and blue is AC input wave form
As noted from wave form waveforms when single diode rectifier
only in circuit with resistive load the output is normal as same
positive input wave form.
When adding inductive load “L” in series with resistance the
negative voltage is in appear due to coil discharge.
When adding freewheeling diode in parallel with load the
negative is removed by discharging in diode.
8. Controlled rectifier
Four circuits was drawn with Pspace as shown above. The
THYRISTOR and diode was used to build this circuits.
Both diode and SCR (Silicon Controlled Rectifier) are
semiconductor devices with P type and N type semiconductor
layers. They are used in many electronic switching applications.
Both devices have terminals called ‘anode’ and ‘cathode’ but
SCR has an additional terminal called ‘gate’. Both these devices
have application dependant advantages.
Diode is the simplest semiconductor device and it consists of
two semiconductor layers (one P-type and one N-type)
connected to each other. Therefore diode is a PN junction.
Diode has two terminals known as the anode (the P-type layer)
and cathode (the N-type layer).
Diode allows current flows through it only in one direction that
is anode to cathode. This direction of current is marked on its
symbol as an arrow head. Since diode restricts the current to
only one direction, it can be used as a rectifier. The full bridge
rectifier circuit which is made of four diodes can rectify an
alternative current (AC) to a direct current (DC).
The diode starts acting as a conductor when a small voltage is
applied in the direction of anode to cathode. This voltage drop
(known as the forward voltage drop) is always there when a
current flow happens. This voltage is usually about 0.7V for
normal silicon diodes.
SCR is a type of thyristor and widely used in current
rectification applications. SCR is made of four alternating
semiconductor layers (in the form of P-N-P-N) and therefore
consists of three PN junctions. In analysis, this is considered as
a tightly coupled pair of BJTs (one PNP and other in NPN
configuration). The outermost P and N type semiconductor
layers are called anode and cathode respectively. Electrode
connected to inner P type semiconductor layer is known as the
‘gate’.
9. In operation, SCR acts conducting when a pulse is provided to
the gate. It operates at in either ‘on’ or ‘off’ state. Once the
gate is triggered with the pulse, SCR goes to the ‘on’ state and
keep conducting until the forward current become less than a
threshold known as ‘holding current’.
SCR is a power device and most of the times it is used in
applications where high currents and voltages are involved. The
most used SCR application is controlling (rectifying) alternating
currents.
Figure above show out wave from 4 SCR with inductive load.
The out from as same when adding freewheeling diode
The out wave form when replace the two SCR in one above the
other in right side the output wave form have a noise as shown
in figure above.
When replace the two of SCR with two diode the output wave
from as the same connecting half wave rectifier.
References
Issa Batarseh, "Power Electronic Circuits" by John Wiley, 2003.
S.K. Mazumder, "High-Frequency Inverters: From Photovoltaic,
Wind, and Fuel-Cell based Renewable- and Alternative-Energy
DER/DG Systems to Battery based Energy-Storage
Applications", Book Chapter in Power Electronics handbook,
Editor M.H. Rashid, Academic Press, Burlington,
Massachusetts, 2010.
V. Gureich "Electronic Devices on Discrete Components for
Industrial and Power Engineering", 2008.
10. 1/2.docxHalf and full wave rectifier
Contents
1.0 Introduction 3
1.1 Power diode 3
1.2 Thyristor drives (SCR Silicon Controlled Rectifier)4
1.3 Single-phase with a half-wave 5
2.0 Pspice simulation 12
2.1 Resistive load: 13
2.2 Controlled rectifier with RL load 13
2.3 Freewheeling 13
2.4 SCR-Electric operation 14
2.5 Full wave control rectified 15
2.5.1Output forms 16
2.6 Output form with freewheeling diode 17
2.6.1Half controlled rectified 19
3.0 References 21
Introduction
The electric energy is distributed in alternating current. The
need for a voltage requires a DC voltage conversion circuit.
If it is necessary a constant voltage of constant value is simply
a diode or, for greater efficiency, a configuration of said diodes
Graetz bridge. But if, as in the case of the drives, you need a
DC voltage which is possible to check the value, recourse must
be controlled diodes, the thyristor drives or SCR (Silicon
Controlled Rectifier).Power diode
The diode, illustrated in Figure 1, is a semiconductor
component, comprising a PN junction. In it, the current can
flow in only one direction, from the anode, A connected to the
area P, to the cathode, K connected to the zone E No 'A valve,
therefore, which leaves transit charges in one direction and
locks in the opposite direction. The diode conducts when the
voltage between the anode and cathode is positive, U AK > 0
(forward bias) does not conduct when it is negative (reverse
11. bias). In a real diode in conduction U AK is very low (about 1
V) and the current intensity assumes high value; reverse voltage
can be high and the diode is traversed by a small current
intensity. The transition from one state to another is not
instantaneous. Switching from a locked state to the conduction
occurs in a few microseconds. What diodes rapid in some tens
of nanoseconds.
The relationship between current and voltage is illustrated in
Fig. 1
Figure 1: relationship between current and voltage
Thyristor drives (SCR Silicon Controlled Rectifier)
It 'a device with four layers, then with three PN junctions, in
which the conduction between the anode A and cathode K,
connected to the outer layers, is controlled by a current pulse
supplied to a third electrode, said gate, connected to the layer P
internal, as illustrated in figure 2. If the voltage U AK is
negative (reverse bias), still lower than a maximum value U i,
max, the conduction is blocked: passes only a weak intensity
and a possible pulse on the gate has no effect. See also U AK is
positive (forward bias), and lower than a maximum value U d,
max similar to that which determines the download avalanche in
reverse bias,, there is no conduction. This, however, may be
triggered by a current pulse on the gate. Once the thyristor
drives entered into conduction remains in this state regardless
of the state of the gate, which loses control. The thyristor drives
returns blocking situation only when the intensity of current
between the anode and cathode, for any reason, it cancels. In
Figure 2 is shown the characteristic i, U AK.
Figure 2: current between the anode and cathode
When the thyristor drives is run there is a small voltage between
the anode and cathode of the order of volts. It therefore has a
power dissipation for which the thyristor drives requires a
system for removal of heat. The choice of thyristor drives must
take into account both the rms value of the current (I rms) that
12. the peak value and the value of the blocking voltage. The
thyristor drives despite the disadvantage of not being able to
interrupt a current triggered, has a wider field of use as regards
the values of voltage and current with respect to the transistor
and, for equal performance, is more economical. In addition,
when using it as a rectifier, the disadvantage of not being able
to be turned off is irrelevant because there is no need for
this. Single-phase with a half-wave
The transistor can also perform the function of switch as the
thyristor drives. In addition the transistor has the advantage of
being able to interrupt the current at any time. This possibility
has not, however, of no importance in rectifying circuits
(different story for the inverter: Converts DC->
AC). Furthermore, the thyristor drives cover a wider range of
values of voltage and current and, at the same performance, are
cheaper. Remember however briefly the operation of the BJT
(Bipolar Junction Transistor)
It 'a component with three-layer NPN or PNP, then with two
PN junctions. The two electrodes are called extreme emitter and
collector, the intermediate base. Conventional current flows
from the collector to the emitter in NPN and PNP emitter to the
collector. The transistor used as a switch and static 'which
switching NPN faster than the PNP. The collector emitter
voltage U CE is positive and also the current I C (from collector
to emitter). In addition to the normal conduction losses
(U CE. I C). Figure 3 in addition to the circuit symbol and the
construction scheme, are shown the characteristics of the
manifold, namely the link between the current and the voltage U
IC CE. The value of I c depends on the value of the base
current. If I b = 0, the transistor as a switch is open, when I b >
0, the transistor can be operated so that the U EC is very low, so
it behaves like a closed switch. The product U CE *
The C corresponds to the loss during the run. To these must be
added the losses that occur during the switching between the
conduction state and that of the block. The latter are the more
significant the higher the switching frequency.
13. Figure 3: Single-phase with a half-wave
The principle for converting an alternating current into a
constant is to use a valve that lets pass the current in only one
of the two senses. Is obtained at the output a unidirectional
current with fluctuations around the mean value, more or less
marked depending on the nature of the load.
The average value is constant if the valve is not actuated
(simple diode), adjustable if it is controlled (thyristor)
Figure 4: principle of the half-wave controlled rectifier
In Figure 4 is illustrated the principle of the rectifier controlled
to a half-wave. The load between P and N is a pure resistance
for which the shape of the current is identical to that of the
voltage. For the II PDK one has u AK = u-u R with u R =
R. the ; u AK is positive for all the positive half wave and
negative for all the negative one because of a resistance current
and voltage are in phase. A pulse on the gate of the thyristor
drives when u AK > 0, it brings in conduction and the waveform
of the voltage on the resistance u R, marked in bold, is identical
to that of the current. Assuming ideal diode during conduction
did u AK = 0.
It has, as we see, the exploitation of a single half cycle, for
which in practice it can use the configuration Graetz Bridge or
double half-wave, shown in Figure 5.
Figure 5: Graetz Bridge or double half-wave
The four thyristor drives form the sides of a quadrilateral fed
between the vertices A and B from the alternating voltage. For
simplicity, it think of a purely resistive load applied between
the points P and N. When u AB is positive d 1 and 2 are biased,
and a pulse on their gate sends them to run while d 3 and 4,
reverse biased, do not lead. The voltage between P and N
coincides with u AB. When u AB is negative (u BA positive)
are d 3 and 4 to be biased so that a pulse on their gate sends
14. them to run while d 1 and 2 are reverse biased and do not
conduct. The voltage between P and N now coincides with the
u BA: P is therefore always positive with respect to N and the
voltage on the load is unidirectional, with the average value,
U DC, adjustable by varying the instant in which it gives the
impulse conduction defined by the angle.
Denoting by U the rms value of the voltage (also called rms
value), U M the peak value, U DC the actual mean value,
UD0 the average maximum value possible, when you get the
urge to turn on the thyristor drives is given at the beginning of
the period, then for = 0, we have the relationships shown in
the figure:
· U M = 1.41 * U
· U D0 = 0.637 U * M * U = 0.9
· U DC = 0.5 * UD0 * (1 + cos o)
Figure 6 shows the waveforms of voltages and currents when
the load is ohm-inductive load, such as the winding of a
motor. And 'considered the case of a half-wave rectifier, but the
considerations are also valid for the bridge rectifier.
Figure 6: voltages and currents when the load is ohm-inductive
load
Figure 7 shows the graphs of the current and voltage of a circuit
ohm-inductive insertion of a sinusoidal emf u when it is half of
the maximum value (phase angle = 30 °). It should be noted that
the current in transient that follows is the sum of the steady
state component of the p and a damped transient the t: i = i p +
i t. The voltage uR = R * i and u is the voltage on the
inductor L = L * di / dt = uu R. At time of insertion, having to
be i = 0 is the t -i = p . We observe that the current starts at zero
and is reset when the hatched area on the right equals that of the
left. The two areas represent the increase and the decrease of
the magnetic flux due to the current that grows at first and then
falls, bringing the energy stored in the magnetic field to a
maximum, requesting the power generator, and then returning it
fully. The two areas are given by the difference uu R u = L ,
15. then the area under the curve u L .
Figure 7: current and voltage of a circuit ohm-inductive
insertion of a sinusoidal emf
As long as you do not give the pulse on the gate, the thyristor
drives does not conduct, u R and u L , then also u RL = u R +
u L , are null and u AK = uu RL coincides with u . Impulse
with u AK > 0 , develops a current (positive A to K), and then
become non-zero and positive voltages u R and u L . The
current increases, reaches the positive maximum, and then
begins to decrease. The magnetic flux and the magnetic energy
evolve in the same way. In the first stage, therefore, the
inductance stores energy which then returns in full in the
second phase, thus the increase of flow of the first stage is
identical to the decrease of the second, as already put the rest in
evidence in Figure 7. When the magnetic energy
decreases, u L becomes negative. When also u becomes
negative the current is not anything yet, then the magnetic
energy stored has not yet been returned in full. The current still
flowing in the direction indicated as positive continuing to
decrease. As the current cancels cancels u R , and at that
moment u L = u . Magnetic energy has been completely
restored. The thyristor drives at this point no longer leads, the
voltage u L vanishes and is reverse biased thyristor
drives: u AK = u <0.
The instant in which the thyristor drives had begun to conduct
up to that in which the conduction ceases, the bipole RL is
applied the voltage u . As the current cancels cancels the
voltage on the load RL. There is therefore a fraction of a period
in which the voltage across the load is negative while the
current is still positive. And 'the interval between the instant
when u becomes negative and the instant in which u L becomes
equal to u, while u AK is nothing, that is the instant in
which the , then u R vanish. In this part of the year returns
energy to the load to the generator.
The average value of the voltage applied to the load, which is
16. given by the algebraic sum of the areas subtended by the curve
u RL divided by the period, decreases compared to the case of R
pure.
If an emf E acts in series with the circuit element RL, as in the
case of the winding armature of a DC motor to speed,
everything happens as described in the previous case, with the
values of u R and u L reduced because instead of u must
consider the difference Eu . Figure 8 shows the waveforms.
It should be noted in this regard that the impulse conduction
should be given when the difference is positive Eu, because in
this case is that the thyristor drives is biased. As the speed of
the engine grows narrows the interval of
conduction The maximum speed is when E is equal
to the average maximum value U C U * = 0.637 M. At the rate
which corresponds to the E, the angle for the pulse conduction
is between 39.5 and 140.5 degrees.
The fig. 8 assumes a constant E which corresponds to a constant
speed of the motor. There is in this respect be noted that this is
the AND of the engine is not actually constant is not constant
because the speed of the motor. When the thyristor drives goes
to run the engine speeds up, then increases its kinetic energy
while the magnetic energy at first increases and then decreases
by the same amount. As the current cancels the motor
decelerates at the expense of its kinetic energy. The speed then
oscillates around a mean value, and with it the BEMF E.
The oscillation has an excursion greater the greater is the load
resistance; equal resistant torque the oscillation depends on the
inertia (moment of inertia) of the engine system-load and
increases as it is smaller.
17. Pspice simulation
In the following figure schematic of diode rectifier was drawing
in Pspice three in 3 cases as shown.
Figure 8: diode rectifier
The first case using diode with resistive load only.
In practice, the half wave rectifier is used most often in low
power applications because the average current in the supply
will not be zero, and nonzero average current may cause
problems in transformer performance. The output as shown in
right figures of resistive load as shown above.Resistive load:
· The objective is to create a load voltage that has a nonzero dc
component
· The diode is a basic electronic switch that allows current in
one direction onlyControlled rectifier with RL load
With a RL load it was observed that the average output voltage
reduces. This disadvantage can be overcome by connecting a
diode across the load as shown in figure. The diode is called as
a Free Wheeling Diode (FWD).Freewheeling
When the circuit is first energized, the load current is zero and
cannot change instantaneously. The current reaches periodic
steady state after a few periods (depending on the L/R time
constant), which means that the current at the end of a period is
the same as the current at the beginning of the period,
SCR-Electric operation
Applying the anode of 'SCR a negative voltage relative to the
18. cathode, you get no electrical conduction, as occurs in a
common semiconductor diode. The SCR can thus be likened to
an open switch.
Reversing the polarity of the voltage, the SCR remains stuck in
contrast to what happens in a normal diode, in which it would
conduct electricity, but the block remains until it receives a
positive pulse on the gate respect to the cathode, of amplitude
such as to put the controlled diode in full conduction. And this
switching occurs in a very short time, of the order of 0.5 us. As
you can immediately deduce, this time is much shorter than that
required by similar electromechanical systems. Once triggered,
the SCR remains conductive without need of any control voltage
on the gate. Preserving this condition even when the gate pulses
are applied to the new command. To de-energize the SCR, that
is, to return to its interdiction, there are two systems: one can
reduce to zero the voltage between the anode and the cathode,
or you can become negative to the anode relative to the
cathode. In this case the alternating voltage proves very useful,
because it passes through zero when reverses its polarity at each
half cycle.
In Figure below is presented the example of a SCR as a function
of electronic switch in a power supply circuit of a light bulb
filament into alternating current. Let's see now the theoretical
behavior.
Figure 9: Circuit theoretical application of a diode SCR switch
function, closed or open, the ignition of the lamp LP.
In the absence of signal on the gate, the SCR behaves like an
open switch, which does not conduct current and the lamp LP
remains off.
But when applying a voltage pulse to each half cycle of the
alternating voltage, the switch is closed and the lamp LP
lights. Not, however, in the fall of its brightness, because the
SCR behaves like a normal diode in series to the circuit, which
rectifies the alternating voltage. In practice, the ignition of the
lamp is reduced to 50%. In Figure below is shown the new
19. condition of the electrical circuit of Figure 5, in which I SCR
turns into a rectifier diode of the alternating voltage.
Figure 10: SCR diode, connected in series with a conductor path
by alternating current, it behaves as a rectifying element,
leaving the way open to the passage of only the positive half-
waves.Full wave control rectified
Figure 11: full wave full control rectifier
Output forms
The output forms in yellow color and input in blue color as
shown below
Figure 12: full control rectifier
Figure 13: wave form with SCR gate pluses (green)Output form
with freewheeling diode
Figure 14: full wave controlled rectifier with RL load and
Freewheeling diode
Half controlled rectified
Figure below show the circuit on Pspice using two SCR and 2
Diode
Figure 15: Half controlled rectified
The outputs form as in figure shown below
The green color is SCR gate pluses and yellow color is output
wave and blue is input voltage
20. Figure 16:The green color is SCR gate pluses and yellow color
is output wave and blue is input voltage
Figure 17: The green color is SCR gate pluses and yellow color
is output wave and blue is input voltage
References
· Kharagpur. "Power Semiconductor Devices" Retrieved 25
March 2012.
· Muhammad H. Rashid,POWER ELECTRONICS HANDBOOK
DEVICES, CIRCUITS, AND APPLICATIONS Third Edition
· Mohan, N. (2003). Power Electronics Converters Applications
and Design. Michigan: John Wiley and Sons.
· Lipo; Kim, Sul. "AC/AC Power Conversion Based on Matric
Converter Topology with Unidirectional Switches". IEEE
Transactions on Industry Applications