Grid Definition and 206 Threads

Hello Physics Forums, this is my first post! I wanted to know how the current electrical grid system works. I mean, not in terms of creation, transmission, and distribution, but rather, how you would draw it on a circuit diagram. I understand that an AC current is generated at the power factory...

I have found a way to construct a pentagon using only the grid system. The internal angles are all within 99% accuracy and all the angles to the 3rd decimal add up exactly to 540 degrees. This is without the use of a compass and bearing in mind that the internal lines intersect at the ration of...

Hello! I am studying the mentioned topic I am confused in calculating the average value of friction factor in sub channels ... please help ?? thank you in advance

I am doing a BSEE and going power side. I am also applying for scholarships and bursaries, and would like to be able to talk specifically about power factors. More than this though, I want to understand it. Most of what I've found so far is very specialized and technical. What good resources...

Homework Statement We fit the plane with a coordinate system, and we consider the set of points with coordinates in ##\mathbb{N}\times\mathbb{N} ##. To link two points in this coordinate system, we only allow unit displacements, and only increasing displacements. In how many ways can one...

when I look at large scale map such as USGS top maps, i noticed that maps' grid are not aligned with the map frame. looking at the declination diagram at the bottom of the map, there's a difference between true north and GN (Grid north) can someone explain to me why the map grid doesn't align...

For an economical PV system, with zero-feed in tariff, for a family home, with no one at home during the day time, the best setup option would be: (some components might be in another) 1) PV, batteries, charge controller, inverter 2) PV, MPP tracker, batteries, charge controller, inverter 3)...

I am on a perpetual quest to understand reactive power. one of the road blocks I encountered is this text: " if inductive load in the grid increases, voltages across loads will drop. In order to maintain power delivered, grid current has to increase" That statement is quite frustrating to...

Greetings, Found this grid from Internet. There was no hint if this was a puzzle but I pretty much sure that it is. Has someone seen this kind of grid before? If so, how to solve this? The link to the grid is: https://www.geocaching.com/geocache/GC6FQYC_pvm-6-chimney

Hi there. I was trying to implement Numerov method for solving second order differential equations (you can see some information of Numerov algorithm at here: https://en.wikipedia.org/wiki/Numerov%27s_method ). At the beginning I've used a uniform grid mesh, all points equally spaced. I'm...

I was trying to implement a variable grid mesh in Numerov's method, while playing with fortran. Numerov method was working well with a standard discretization, but when I tried to implement this variable grid, things came to look as if the 'metric' of the function were depending on the...

Hi I was wondering if someone could help me understand and explain to me how one can control the frequency of the grid from help of the active power (frequency -> power angle -> active power) and how reactive power can be used to control the voltage level. My thoughts: Voltage Control: I don't...

When an alternator is synchronized to the grid, its voltage and frequency are same as those of the grid. So, it shouldn't take any load at that instant. How is it brought into operation then? What is the procedure followed practically? My book says prime mover is given some extra energy so the...

The motivation for this thread comes from physics, but I'm posting it in the maths section as the question is more of a mathematical one and less concerned with the underlying physics. In cosmology, they often talk about closed universes with positive curvature, or non-Euclidean elliptic...

Is there a way to create a grid here on PF that has square elements? I ask because I'm yearning to make a post that will require a Cayley table.

Homework Statement In a grid O(0,0) A(7,8) find the number of paths that 1. pass through (3,4) 2. don't pass through (3,4) 3. pass through M(2,3) AND N(4,6) 4. DON'T pass pass through M(2,3) and N(4,6) 5. pass through ONLY ONE of M(2,3) and N(4,6) 6. pass through AT LEAST ONE of M(2,3) and...

Hi all, I am looking for a precise definition of " Crow Flies Distance" on a rectangular grid. I have not found a precise definition yet, but from what I have read, I think it would be the standard Euclidean distance ## d((x_1,y_1),(x_2,y_2)) = \sqrt {( (x_1-x_2)^2+(y_1-y_2)^2}) ## Is this...

Hello, I would like to develop a testing method to detect window defroster grid failures. Rear windows has 12 heating wires painted to the glass and cca. 2% are faulty pieces. I tried to measure the resistance, current and voltage drop of good parts and compare results with those where was at...

Hi, I have written some codes for the finite difference solution of diffusion equation (\frac{\partial c}{\partial t}= D {\nabla^2 c}, where c is the species concentration and D is the diffusion coefficient) as follows: DO k= 1, tsteps+1 DO i = 2, zsteps DO j = 2, rsteps...

pls help with the formula on solving these the easy way. It took time for me to find the answer by drawing it literally. my answer is 334 squares.

Hi, I am working on Solar systems in Australia. I want to know the Australian standards for grid connected PV systems for voltage, power factor, reactive power etc.

https://brilliant.org/problems/hexagonal-grid/ I've been pondering on this but not being able to solve.I mean applying Kirchoff's law here is of no use. Any ideas?

A quick calculation shows that across the continental United States, spanning about 3000 miles, there is a delay from east to west coast of about 1/60th of a second. 3000 miles divided by 186,000 miles per second. This is a full cycle phase variation cost to cost. Is there truly "The Power...

Could you solve this?

I ran across a project at the Univ. of Tennessee that has deployed a network of frequency meters around the power grid in the US. see http://fnetpublic.utk.edu/anglecontour.html I understand the frequency excursions may indicate unexpected events like generator trips or loss of load. What do...

Here is a difficult probability question I found interesting and thought I'd share: Suppose you are standing on an infinitely large square grid at the point (0,0), and suppose that you can see infinitely far but cannot see through grid points. Given a random grid point z = (x, y), where x and y...

Im trying to construct a regular grid in a rectangular box in 3 dimensional space heres what i have to work with: x has a range between xmin and xmax y has a range beween ymin and ymax z has a range between zmin and zmax the total number of points is limited to a specific number n i want the...

I've just wired in a 1kw grid tie inverter, feeding the power from solar panels into the mains grid, ( in Thailand , so no rules or regulations). There are some problems I've noticed. Toaster buzzes , but works. Induction cooker won't work, lights come on , fan works but no heat delivered, when...

When the beam of electrons reflect back to the grid due to the repeller voltage in reflector plate ,how the grid decelerates the returning electrons ?? And how they release their energy to the grid ?

Dear experts, I´m trying to model in ANSYS Mechanical (v14.5) the linear buckling behavior of a cylinder made of BEAM4 elements under combined loading (axial compression and bending moment) applied at the ends. How should I set up the boundary conditions of a cylinder to keep rigid the ends...

Hi, I checked the forum rules and homework / coursework is not allowed so I am not sure if this is appropriate or not. Feel free to guide me through appropriate forum and/or lock this thread if such questions are not allowed. The question I have is mostly related with my research and since I am...

Hi everybody, I need to discretize a differential equation. The grid that I am considering has a different grid spacing along the three space directions. That is, hx different than hy and hz. For that purpose, I would like to discretize the differential equation through the Mehrstellenverfahren...

Hello, I would like to know, how to calculate the number of grid lines( or loops) in a strain gauge. I'm trying to calculate the output form the each grid lines. Thanks in advance

Here is my single triode vacuum tube amplifier circuit I understand there needs to be a bias on the grid otherwise the signal will be rectified -not amplified. Is biasing the grid as simple as running a resistor in-between the grid and the cathode on the power supply like this (in red)...

Hi, So I trialed a 400W grid tie inverter which I had laying about to experiment with lowering the amount of energy the house is drawing from the grid with a single 100W solar panel I have on the roof to charge some batteries. I have a "smart meter" which measures how much power the house is...

Homework Statement In America power is supplied at 110 V. In Australia power is supplied at 240 V, however American lights are routinely used in Australia. a) How is this possible? b) Calculate the power that a pair of 1000 W 110 V light would dissipate when plugged into a 240 V system in...

Hi everyone. I hope this is in the proper place - not sure where to put it. Anyway, I am working on an optimization problem in the research I am doing and my partner and I have found that in order to quickly converge on a solution using a specific PSO (the firefly algorithm - it's awesome, look...

Why is it that the width of a wire grid polarizer has to be less than the wavelength of the wave which I want to polarize? What would happen if the width was a little bit more?

Hi Forum, once again I seek your help I have a very good understanding of rotating magnetic field due to stator, armature reaction, and the phasor diagram. from energy point of view it is very clear that if Gov increases, while output voltage remains locked by the gird, Amp will increase...

Something that's been bugging me, but unable to find an answer for.. The speed of light (in a vacuum) is absolute, well not really, its relative to the space/time its in. ie. The distant galaxies are moving away from us, but their local light speed is relative to their space/time. So since...

Hello! I'm currently working on an algorithm that converts SPH (smoothed particle hydrodynamics) data to an Eulerian grid. Basically, the problem is this: each sph particle has an associated smoothing length, which is effectively the radius of a sphere centered at the sph particle's position...

Hi, In Conway's experiment it is said that the changes in the grid happen simultaneously between each tick. How is it possible for the changes to happen simultaneously since all cells are dependent to one another ? Can anyone explain this and give an example ? Thank you in advance, Alex...

Since everything in the universe can be calculated using 3D grid mathematics, it seems logical that universe would be ON a grid of some sort. So then what would the grid be, exactly? After dwelling on this idea for a while, I came to the conclusion that it would have to be space itself...

For a University project I need to somehow model the effective performance of a ground grid in the event of a fault caused by a lightning strike. We would need to prepare different test cases for different sizes and grid configurations in order to carry out different analysis and find the...

I am working on a project. I have completed designing PV module in simulink. I have also added MPPT algorithm and Boost Converter. Now I want to connect it with a grid. Can anybody tell me the circuit diagram?

Hi all. I have a grid with 4 points, A, B, C, and D. Each valid move is either going to the right for one block or going down for 1 block. Here is the grid. I need to calculate the following: a) How many different valid routes from A to D? b) How many valid routes from A to D that must avoid...

Whenever the subject of cyber security is raised, attacks on the power grid are the first example offered almost all the time. Nobody should be surprised then that there is a tremendous amount of activity and huge amounts of money being spent on grid cyber security. Much of that is being...

This may be more of a math problem; it arose out of my curiosity of manipulating LED matrices and reminds me of a traffic flow problem, but I am sure it can model a variety of applications. Its not a homework problem but would probably make a good one! You have a 3x3 grid of points, each...

Start with an infinite 2d grid of cells, with each cell randomly colored black or white (50% chance). Now take the graph G whose nodes are the cells, and with an edge (A, B) if A and B are adjacent in the grid, and the same color. What is the average size of a connected component of G? Is it...

Any ideas on how I could put together a smaller prototype of a smart grid system? Just brainstorming here but here are a few things I was thinking Grid in a BOX Marketability is key right? So why not design some kind of "smart box" system that residential home owners can use in their homes...