The Power System: In General
Our final aim in one sentence is “to make safe electrical power available to all 24*7 round the year, round the decade and so on”.
And that phrase says almost everything we require to do.
As an electrical engineer that’s all what we want to do in our life, everything for it. From now on, anything we think or do professionally is going to manifest this final aim, have you ever come across anything holier than this.
We have very carefully phrased the paragraph to capture whole of electrical engineering in its entirety.
So it goes….
“Safe electrical power”: indicates the first necessity i.e. the safety of electrical power, which is all about operating the power system in a strict pre-defined range of parameters including active and reactive power levels, voltage, current, power factor, and distortions.
“Available to all”: indicates the affordability and treating electricity as not just mere commercial commodity rather a basic service for all. The economy of the power system is essentially a science of figuring out how much to turn the knob of which power plant.
“24*7 round the year”: set for us the reliability feature of the power system. Now, this includes very smartly designed protection systems which largely sits idle just waiting for the time to be called in.
“Decade and so on”: indicates the security feature of the power system that we wish to keep on powering the world as long as human exist which requires to keep looking up for new sources of energy. Notice we may be interested in anything that can jiggle the electrons in the wire at 50 Hz. So solar, wind, geothermal, tidal, and even Nuclear Fusion and Fusion are all the cards we keep stocking in our free times and weekends.
Any subject you will ever study have its application in at least any one of the above-mentioned categories. Just fast-forward how the subject will help in achieving this final aim and you will get hugely motivated and interested to take it.
Another facet we miss is enabling ourselves with the tools of engineering. And one of them is Simulation Software. The simulation software has immense capability to add to the fire and gives wings to our imagination. No doubt anything that you could ever do with simulation software could also be done by your hand on a white sheet. But the sheer advantage of vivid visualization of things, accuracy and validation of results and ease with which things could be done is truly great. On your desktop you can build anything you want a large power system to visualize the load flow and system natural frequency (as we did in Harmonic Resonance Study and fault analysis) using MATLAB, a microcontroller-based system to do crazy things (as we did in Harmonic Analyzer) using Proteus, an analog circuit comprising of the wonderful op-amps to perform any mathematical functions (as we did in power module) using MATLAB, you can plot with extreme accuracy and detail and easiness the response of any transfer function using bode-plots, pole-zero plots, Nyquist plot, (as we did in designing buck converter) using Scilab You can tweak and play with the drive system of any machine like PMSM, BLDC, Induction motor, DC motor, etc.
One of the crucial practices in engineering is a sound appreciation of comparison between all ranges of systems and equipment.
Various systems types (machines, circuit configurations, etc.) are available at our disposal, what enables us to make a good engineering decision to go with a particular type and not with another for a given specific application is our ability to distinguish between all options available.
Will you use a DC machine, a Squirrel Cage Induction Machine, or a Synchronous Motor?
Will you use a Cylindrical Rotor or a Salient Pole Rotor Synchronous generator?
Will you use a Ward Leonard Drive or a Static Ward Leonard Drive?
Will you use an HVDC line or an EHV-AC line?
Will you use a Voltage Source Inverter Drive or a Cycloconverter Drive for V/F control?
Will you use a Synchronous Condenser or a Static VAR Compensator?
Will you use a MOSFET or an IGBT?
Will you use an Overcurrent Scheme or a Differential Scheme for transformer protection?
It will take another 5000 words to carefully analyze which choices to make under which conditions, so we will leave on your own to figure out why!
Sooner or later we will be confronted by all these sort of real-life MCQs in our career, to make a good, economic and futuristic decision one has to be very critical minded while studying and comparing all varieties of systems among systems.
Another thing we want to bring to your attention is having a mindset to pay attention to all the electrical engineering stuffs going around you. Like noticing the voltage and power levels of various equipment and systems (traction operating at single phase 25 KV, wattage ratings of household items), noticing design and structural details (the reason behind the shape of a three-pin plug), visualizing and analyzing waveforms and distribution of fields in 3D space of the street power lines, even noting which brand of EV uses which types of machines and so on. This helps in either answering a wide range of short questions asked throughout and more importantly helps understand and connect better while actually studying those things.
Having a technical discussion with a loving friend can immensely help in getting oneself easy and clear with the terms and concepts which are otherwise sound so technical. It is a very effective way to sharpen one’s engineering language accent of talking and thinking. So, we are not just engineers on our working table, in our classes and in our labs, to unleash the full potential we need to be literally obsessed with these stuffs in all spheres of our lives from personal to public!
Since we have so much stressed upon enabling nature of these tools learnt in four-year course, we must now lay down its disabling feature.
And lets us illustrate this with a small regular classroom incident:
In our second-year lecture, Prof. AKP Sir asked us to differentiate between the underground system and the OHT system, each of us made him count every technical detail like less corona loss, lightning protection, fault location, etc., very technically. But all of us missed the most critical point for which some great engineer had devised the underground system for, we failed to see that the OHT occupies more physical space than the underground system. That was the evidence that our natural intellect was hijacked by the professional knowledge.
We had acquired the technical knowledge in the wrong motive. We think that it is the most crucial tool to enable us to see different and otherwise difficult things, whereas the truth is that it is just an aid to our natural thinking to understand and describe the things easily. We are so trained to think in a loop that we literally miss very crucial points which if we were not trained could have thought about.
So, it is very important to be always grounded in terms of thinking and not take many facts for granted.
In the end, we have:
Engineering in the 21st century has become quite well defined, we now have sophisticated understanding of things, unlike in the past when people considered magnetism and electricity different. Now problems have become accurate in their own terms, there are much fewer compelling questions of “why” rather than “how”. For example, how to accommodate renewables on the grid, how to solve the battery problem, how to spin motor greener and smarter, etc. Throughout the course we are presented with all the necessary tools and hacks which are very logical and easy to understand with little mind-force.
On the other hand, in our everyday life due to some reasons we take up the wrong fight. We are busy somehow dogging the assignments and the quizzes and so on, completely missing the true fight we actually are in, and that makes a difference between enjoyment and getting oneself literally tortured.
NOTE: All the statement made in this blog are authors own mere speculations it may be wrong, so an active reading is greatly expected. Don’t’ keep the statements until you yourself get sure of validity.
Be Critical, Be a CEV!