Whether you are new to the industry or are well seasoned and want to review some of the basic information that you learned in the past, these courses and lessons will clearly outline what you are looking for. “Power Systems Electric” is On-Line training that bridges the gaps between textbook theories and practical power systems experience. As a retired electrical engineer who has gone through the experience of developing a career in electrical power systems, I know how frustrating it can be to try and find the answers, so I put together these courses that I feel would have been a major help to me in my development. I have also taken suggestions from students of what they would like to see in addition to these courses which I have given live in person.

Basic Electrical Learning

For those new to the industry, there is a beginner’s group of courses that cover the “Fundamentals of Electricity ” including DC and AC Circuit Analysis. These lessons examine such basics as Ohm’s Law, Series, and Parallel Circuits. The first, and perhaps most important, relationship between current, voltage, and impedance, “Ohm’s Law”, and its relevance to Series and Parallel Circuits. Subsequently, this will lead to the development of Kirchhoff’s Laws as they help to further analyze Network Analysis & Metering Circuits.

Conductors and Insulators are investigated along with their connected components, Capacitors, Inductors, and how they are influenced by Electromagnetism.

Alternating Current (AC – an electric current that periodically reverses direction) is the form in which electric power is delivered to businesses and residences, and it is the form of electrical energy that consumers typically use when they plug kitchen appliances, televisions, fans, and electric lamps into a wall socket.

The abbreviations AC and DC are often used to mean simply alternating and direct, as they are applied to current or voltage.

These AC courses deal specifically with sinusoidal waveforms and will provide the student with the basic understanding of working with circuits involving Alternating Current, which includes sinusoidal waveforms, vectors & phasors, reactance & impedance of R,L,C circuits, as they relate to the basic laws and theorems of electricity. This includes working with AC Power, Power Factor, Resonance, Complex Numbers, Reactance, and Impedance

Advanced Electrical Learning

These Courses involve subjects such as “Short Circuit Analysis for HV Three-Phase Systems ” which introduces the student to the basic concepts of fault studies on a high voltage three-phase system. System modeling is then used in order to aid in this process, with the ability to move between asymmetrical and symmetrical systems. With hey Searle and extensive study of “Per Phase” & “Per Unit” methodologies system faults are analyzed with the use of symmetrical components.

“A Per-Unit System ” is the expression of system quantities as fractions of a defined base unit quantity. Calculations are simplified because quantities expressed as per unit do not change when they are referred from one side of a transformer to the other.

In these courses, you will learn exactly what Per Unit Analysis is, the main advantages of using it, how manufacturers of equipment use and rate their products, and the technique of converting to and from the Per Unit system.

Several examples of working with Per Unit are demonstrated in this crisp clear presentation. When you finish you will have a though understanding of this subject.

It is important for all power engineers and technicians to be familiar with the concept of Per Unit as it is being used and referred to every day in power flow, short circuit evaluation, and motor starting studies.

The method of “Symmetrical Components ” is used to simplify asymmetrical three-phase voltages and current analysis by converting the unbalanced system into two sets of balanced phasors and a set of single-phase phasors, or symmetrical components. These sets of phasors are called the positive, negative, and zero sequence components.

An understanding of this method is essential for the understanding of fault analysis and modern-day protection schemes. These courses will provide you with the knowledge to comprehend the concept and how it is applied.

Supplemental Electrical Lessons

In all power electrical analyses, the student will encounter special Trigonometric and Mathematical identities and equations. This site contains special supplemental lessons that zero in on those identities and equations. For example, there are lessons that take you from the “Fundamentals of Trigonometry ” to the more sophisticated requirements in electrical engineering. As you work and study in electrical engineering you are going to run into proofs and equations that are based on trigonometry. A good example of this is when studying AC current, voltage, and impedance calculations, phasors or vectors are used and combined mathematically. Further adventures into complex power will also require a knowledge of trig functions and identities. As a student of this course, you will be introduced to these or at least re-introduced to these that may have been long since forgotten.
In mathematics, “The Derivative of a Function ” of a real variable measures the sensitivity to change of the function value (output value) with respect to a change in its argument (input value). Derivatives are a fundamental tool of calculus. For example, the derivative of the position of a moving object with respect to time is the object’s velocity: this measures how quickly the position of the object changes when time advances.

Specialized Electrical Lessons

Specialized lessons include the “Protection & Control(P & C)” principles of high voltage stations. HV Bus Differential Protection is studied along with restrictions due to CT saturation & mismatch and its solution, “Restraint Differential Protection”.

High Voltage Circuit Breakers are examined as to the various Types (Oil, Vacuum, Air Blast, SF6), their Controls as well as the introduction of potential transformers & current transformers, and their use in conjunction with the relevant instruments such as ammeters, voltmeters, watt meters, and energy meters.

Other lessons include the study of “Transformers ” including core construction along with losses, cooling, and mitigation techniques. Three-phase transformer configurations are studied along with harmonic distortion, CT saturation, and on-load tap-changer problems and how these problems are dealt with. Over-current and restraint differential transformer protection is developed along with a look at some examples of ” Old School relays” as well as modern IDE (intelligent Electrical Devices) relays.

Transformer Connections: (Y – Y; Delta – Delta; Y – Delta; Delta – Y & Y – Zag Zig) are examined along with Transformer Clock System Vector Nomenclature.

Lastly, there is a special section dedicated to “Single and Three-Phase Metering “, including old analog and new digital kilowatt-hour meters.

Conclusion

Regardless of whether or not you are new to the industrial power system, you’ll find what you’re looking for on this site in the way of training. In order to review or select any of these courses, left-click on any of the blue highlighted hyperlinked words of this posting or on “14 Courses Available” from the top menu of the landing page. All of the courses have a free introduction

As a bonus and in the way of a thank you, for your interest in PSPT’s WEB (and Blog) page, I’m making available my 50-page “Electrical Power” crib sheets. These were prepared for use with my courses that are available on this site. There is one section associated with each course and is extremely valuable while viewing the course, as well as a recall of the pertinent formulas and information after the fact. The contained information is also useful during any technical career as a quick reference from time to time. Simply click here or on the picture to the right to be taken to where you can download this item.

November 27, 2024

Blog #39 - Calculating Another Circuit Using Thevenin’s Theorem

November 27, 2024/ Graham VanBrunt

As part of my problem series in this video, I will be using Loop Analysis Thevenin’s Theorem

Once I am finished with this series of problems I will be posting them in my Stan store, at this web address…https://stan.store/GVB

Find V0 in this circuit using Thevenin’s Theorem.

Firstly we need to determine the open circuit voltage, V0,

To begin the process remove the 2 kΩ resistor.

The open circuit voltage at this point is VTH our Thevenin voltage. The Thevenin resistance is then found with the sources in the network removed (voltage sources short-circuited and current sources open circuit)…let’s find the Thevenin voltage first by letting the voltage drop across the 4 kΩ resistor be V1…and letting the voltage drop across the 3kΩ resistor be V2. Then

VTh = V1 + V2…we now need to determine these voltages.

We know that the current through the 4KΩ resistor… call it I1…is 4 mA due to the current source. Then clearly, Ohm’s law tells us that…

V1 = I1(4kΩ) = (4mA)(4kΩ) = 16V…to find V2 we need to know I2. and KVL around the loop I2 yields this equation

-12+6k(I2 –I1)+3kI2 = 0…well we know what I1 is so we can plug 4mA into our equation and it becomes

-12 + 6kΩ(I2 – 4mA) + 3kΩI2 = 0…

we know that this is a KVL equation so that all the terms in this equation are going voltages and because we built the equation using thousand Ohm resistors and milliamp currents then I'm going to uncluttered the equation to give us something easier to read…

-12 + 6I2 – 4 + 3I2 = 0

This gives us one equation with one unknown… I2. Therefore we can quite easily solve for the value of I2. Collecting like terms we get 9I2 on the left-hand side of the equation and we'll bring all of our whole numbers to the right hand side of the equation which change from negative numbers to positive numbers and adds up to 36. We can now solve the equation for I2 giving us I2 is equal to…

4 mA… now V2 is just a voltage drop across the 3kΩ resistor which is 3 kΩ times 4 mA = 12 V. This seems odd…We have a 12 V power supply feeding into a 6kΩ resistor. You’d think there is some voltage drop across the 6kΩ resistor…upon closer examination though we see that the current through the 6 kΩ resistor is I1 - I2 or 4 mA - 4 mA which is equal to zero, so the voltage drop across the 6K on resistor is zero meaning V2 is definitely going to equal the same voltage as the power supply 12 V.

Finally we can solve the equation for VTh which… is 16 V+12 V which…is 28 volts.

The Thevenin equivalent resistance is found by…zeroing all sources and looking into the open circuit terminals to determine the Thevinen resistance RTh. From the network we see that the 6k and 3k Ohm resistors are in parallel and that combination is in series with the 4kΩ resistor.

Thus RTH =4kΩ+3kΩ||6kΩ = 6kΩ

Therefore, the Thevenin equivalent circuit consists of a 28V source in series with the 6kΩ resistor. If we connect the 2kΩ resistor to this equivalent network we obtain this circuit. V0 is the voltage drop across the 2kΩ resistor which we can find using voltage division…which gives us V0 = 7 Volts

Hey there, tech enthusiasts and smart home aficionados!

I'm thrilled to announce that I'll be diving deep into the world of home automation in an exciting new series of blogs and social media posts. Get ready to transform your living space into a futuristic haven of convenience and efficiency!

In the coming weeks, I'll be sharing my insights, reviews, and tips on the latest smart home gadgets and systems. We'll explore cutting-edge products that will revolutionize the way you interact with your home, from AI-powered assistants to energy-saving devices and advanced security solutions.

If you are ready to elevate your living space with home automation, now’s the perfect time to transform your home into a smart, efficient household! In order to explore an incredible range of innovative products that cater to all your smart home needs.

Simply this website…https://bit.ly/4eGRRtu

Don’t miss out on exclusive discounts available for a limited time! Take the first step towards a smarter home and discover how easy it is to enhance your lifestyle with cutting-edge technology. Your dream home awaits!

Remember, this video has been brought to you by PSPT, where you will find electrical training videos when you go to this web address, which will also gives you a free copy of my 50 page crib sheets that you can use while viewing any of the courses or just keep handy during your every day work.

Also remember, from my previous videos that you can obtain the latest discounts on battery systems at these web addresses…

➜ Eco Flow…https://shrsl.com/4pthi

➜ Bluetti…https://bit.ly/4fDx2Ba

➜ Anker…https://shrsl.com/4pplo

➜ Jacquery….https://bit.ly/3YCiw5Y

These sites not only give you unique battery systems that can power things from cell phones or laptops to a complete backup system for your home. Just go to these sites and see what they have to offer. There is no cost or obligation to just browsing.