Transient Definition and 170 Threads

Hi, So we're doing this Lab on Transient reactance of a synch generator and I'm reading Sarma's classic: Electric Machines Steady-state theory and Dynamic performance p. 474-479 But I can't see how to get the actual exponential time constants for the sub-transient and transient reactances? Thanks

Hi. I have problem simulating this circuit in Multisim: (LTSpice) Here is scheme from Multisim: When I run transient analysis, I got this: ------ Checking SPICE netlist for Design3 - Saturday, September 26, 2015, 10:58:03 AM ------ ======= SPICE Netlist check completed, 0 error(s), 0...

Hey Guys! Hi Guys! Well I am new here and I have to confess that I somehow got stuck in a 3D transient electromagnetic simulation of a solenoid actuator and… I’m a mechanical engineer^^ So I would appreciate some help of you guys! 1. I imported the geometry from CAD-files. But I remodeled...

Hello PF! I have some questions regarding the accumulation term for the energy balance on a variable volume system. Suppose we have a tank storing a liquid substance. The tank has a moving boundary at the top, which can expand unlimitedly. The system has a mass input \dot{m}_1 and mass output...

If a purely inductive circuit is excited with an AC source, a transient occurs before reaching the steady state 90 ophase shift i.e. the current takes some time to shift the phase depending on the switching instant. Is there any such transient in CT?? Suppose the primary circuit is initially off...

Homework Statement This is a problem regarding transient heat conduction in an undefined semi-infinite solid, initially at a temperature T0 whose surface temperature is suddenly raised to a new constant level at Ts. I also supplied the problem as an attachment for ease in explaining the...

Homework Statement An accelerometer is connected via a length of coaxial cable to an amplifier. The arrangement is modeled by: (a) a Norton generator in parallel with a capacitor (CP) representing the piezoelectric crystal within the accelerometer; (b) a lumped capacitor (CC) representing...

Homework Statement I felt some more practice for this was needed and I want to make sure I really understand. The circuit is given: I'm asked to find the current in the inductor just before the switch is closed ##( i_L(t = 0^-) )##. Then I'm asked to find ##v_L## at the instant just after...

Homework Statement I had a question about transient circuits. I was asked to find an expression for ##v_C(t)## at any time ##t## for the following circuit. My work is shown in the image below. Then the response is interrupted at ##t = 50 ms## by the switch being opened and I'm asked to derive...

Homework Statement In given network (voltage source V & switch K) , a steady state is reached with the switch k open .At time t=0 , switch k is closed. Find voltage across C before switch is closed? and i1 &i2 at t=0+.Also values of di1/dt and di2/dt at t=0.Homework EquationsThe Attempt at a...

Hi All I have done transient stability simulations on isolated electrical network using ETAP 7.5 software. Problem: On buses Faults generators return to stable stade But on cable faults, rotor angle is diverged so the system is not stable. To be noted that we have 2 SOLAR generators of 5MW...

Homework Statement In the given circuit (voltage source is V) , we have to find initial and final values of current and also di(0+)/dt , di2)0+)/dt , d2i1(0+)/dt2 . Now , by intial and values of currents , does they mean i(0-) and i(0+) or the discharging or charging current?? nd how to form...

Homework Statement Sketch, on a set of common axes, waveforms to represent the transient response of circuits having transfer functions with the following parameters: a) ζ = 0.5, ω = 1×10^3 rad s^-1 b) ζ = 0.2, ω = 2×10^3 rad s^-1 c) ζ = 2, ω = 1×10^3 rad s^-1 Homework...

Hello, I have modell in Ansoft Maxwell sumulate and need to transfer (import) it in Workbench ANSYS for the next step (Thermal analysis). How can i import it? Thank.

Hello, My question is out of curiosity and pertains to transient currents and their possible effects on any electrical equipment. For example, The various electrical components(infotainment systems, headlights, radio etc) in a car are “grounded” on the chassis, If a live wire from a electricity...

Hi! I'm learning about solving transient circuits using the differential method and step-by-step approach and I'm just wondering if there's any advantages or disadvantages to both. Are there any problems which will be easier solved using the step-by-step approach vs differential? Thanks!

Homework Statement Use the step-by-step method to find vo(t) for t > 0 in the circuit in the figure below. Homework Equations V=IR, KVL, Mesh Analysis, Voltage Division, Solution form of first order equations The Attempt at a Solution Finding the current through the inductor before the...

I have derived the weak form of the transient heat conduction equation (for FEM) and I am having trouble trying to assemble the mass matrix This is the PDE: \frac{\partial U}{\partial t} = \alpha \nabla^2U This is the equation for the mass matrix for an element: M^e = \int \Psi...

So in a lumped parameter system, we use the ln(Θ)=exp(-hAt/ρVc), where Θ is non-dimensional temperature. This expression has 't' i.e. time in it. So does this mean it is used only for transient problems? Also, does the Biot number Bi tell us anything about whether a problem is in...

Hello, I am graduate student in NE within the US. I am working on a grant that examines a small (10-100 microns) ceramic film region on the outside of the cladding region. I have assessed the neutronic impact, as well as a thermal impact (heat transfer coefficients, etc.) of the additional...

Homework Statement Find the expression of the current "i" by terms of time. The answer is 3e^(20t) Amps Homework Equations i(t)=I_final+(I_initial-I_final)*e^(-t/τ) The Attempt at a Solution I have found the initial current as 3 amps. However, after the switch had been changed for too long...

Homework Statement Determine the current flowing when the capacitor has been discharging for 5μs Capacitance=400 pico farads which is charged to 10v through a 50kΩ resistor. Homework Equations Vc = ve-t/CR The Attempt at a Solution So Vc =Ve -t/CR -t/CR =...

Homework Statement For a series circuit with the following components: 1. Vin(t) 2. 1K resistor 3. 100 mH Inductor 4. 1 uF capacitor 1. Write down the differential eqn. for Vc in the circuit. 2. Solve the DE, calculate the natural and forced response with the following initial...

Hi I am having difficulty explaining to my mechanical engineering supervisors the following: When a pumped storage unit is in generation mode, synchronised to the grid and in steady state and the guide vanes/wicket gates are opened more to allow more water flow and therefore more power...

Homework Statement Use Laplace transforms to derive an expression for the current flowing in the circuit shown in the figure, given that i = 0 when t=0 Homework Equations Expression for the current in an LR series circuit I(t) = V / R (1-e-Rt/L) V - Volts (6V) R - Ohms (10Ω) L...

Homework Statement A capacitor of 0.1 F and a resistor of 5 Ω are connected in series; the combination is applied to a step voltage of 20V. Determine the expression for the: (a) current that flows in the circuit and (b) the voltage across the capacitor in time domain. Homework Equations...

If I have a circuit with R = 1Ω L = 300μH V = 20V i0 = 5A I know that I can use the equation at the bottom of page 13 to calculate the current rise given any starting current and input voltage: i(t) = (V/R)[1-e-t/τ] + i0e-t/τ This is fine, and stops increasing at 20A as expected...

Hi, I have been given a question which involves analysis of a series RC circuit. The system in question has a 4Ω resistor in series with a 1000μF Capacitor (the capacitor is to be considered as completely uncharged before t=0). There is a 12V supply in the circuit. At t=0, a switch is...

Homework Statement I have a circuit containing an inductor, 2 resistors and diode in series however there is also a switch. The Attempt at a Solution I thought that when the switch is closed there would be no current flowing through the right side of the circuit (resistor and...

Homework Statement =137200878&filters[recent]=1&sort=1&o=0"]http://s741.photobucket.com/user/pforpashya/media/studybitch/untitled_zps4cac3f38.png.html?filters[user]=137200878&filters[recent]=1&sort=1&o=0 Homework Equations The Attempt at a Solution Well I already got the solution and also...

Morning all, This is probably going to seem absurdly simple, however I need to do a very quick conduction calculation as part of a much larger problem I am working on. I was wondering if anyone would be able to give me some pointers as time is of the essence. The scenario can be simplified as...

I was watching TV and noticed a lot of flashing lights outside which was coming from a distant storm. I got my camera and proceded to take pictures. During one of the 8 second exposures I saw a large bolt rise from the top of the storm cell then it quickly collapsed but then it rose again but...

Hi, could someone help me to define what is transient or in other words short-lived absorbtion? Maybe the general defintion could sound something like: In transient absorbtion the sample is excited with some kind of source(electrons, laser ,x-ray and so on) and then flashed with wide spectra...

Hello! I'm currently working on a solenoid and trying to simulate the response of a ferrous rod in the coil. I've been using FEMM 4.2 for my magnetostatic simulations, and Pspice Schematics 9.1 for the circuit part. I was thinking of combining the two by using scripts to let FEMM run through...

Hi all, I have a general query about voltage drops. Below is an example of the sort of question i am dealing with. If we have: a series circuit with a 14v dc supply, with a resistor of 200ohms and an inductor with inductance 0.6H use the exponential equation to work out voltage across the...

Hello, I calculated the transient response of a weakly coupled transformer (M ≠ L1L2), for a heaviside step function input. I get a decaying oscillatory response, even though I didn't include any capacitance, can this be? If interested here is the angular frequency I get...

A pn junction diode is driven by a voltage +E to -E volts preodically when voltage is +E its forward biases and vice versa. when in forward biased a current I flows through it, now if voltage is reversed to -E, current is still I (in reverse direction). This then stay constant for a time...

Hi, I'm having a bit of difficulty deriving the time to max activity for the case of transient equilibrium for a parent-daughter. This is where I want to get to , tm = (1 / (λ1-λ2)) * 1n(λ1/λ2) I believe there is an alternative equation for tm as well expressed in terms of half-life...

Hi , Hope someone could offer me a solution to this piece of code, the code below shows a period in time of a synchronous generator transient response, My scaling is the problem as I am not getting 50 Hz 230 volts, your help would be appreciated.. My efforts so far are % Transient...

1D solid, 0<x<L, with the following boundary conditions: The whole solid is at T = T1 at t=0. x = 0 is held constant at initial temperature T1 for all t. There is a constant flow of heat, dQ/dt out of the solid at x = L. T(0,t) = T1, T(L,0) = T1, How do we go about solving the heat equation...

Homework Statement The main problem is that I need help using Multisim for transient analysis of a simple LC parallell circuit. I am doing something wrong. C= 3*10^-5 F L= 3*10^-3 H The Capacitor is charged to 10V What happens to the energy of the capacitor when we connect it in...

Homework Statement A series R-L transient circuit is connected to a voltage source of E= 40V through a switch as shown. Suppose the switch is closed at time t=0μs and it was observed that the current iL flowing through the inductor rises to 4mA at time t=20μs and remains at 4mA after t=20μs.(i)...

how do you "indicate transient terms" when y just equals 1 ? t is the dependent variable in this problem and I'm told to "indicate transient terms". Well, t=1 so is this a trick question or did I do something wrong?

This paper 'Provocative radio transients and base rate bias: a Bayesian argument for conservatism', http://arxiv.org/abs/1211.7338, discusses transient radio signals as possible signs of extraterrestrial intelligence. I knew of the 'WOW' signal, but, was unaware of other similar detection events.

Homework Statement Ok so I have attached the question I am working on. Basically when I have the circuit before or after switching in steady state I believe the current will equal zero. However if this is the case, how do I determine what happens immediately after switching? Homework...

1. The problem statement See attached question - So I have this inductor transient question and can't seem to get the right answer. Basically I don't know how to determine the current in steady state after switch operation.Homework Equations tau = L/C iL = a+be-t/tau V=IR The Attempt at a...

The switch in the diagram below has been open for a long time prior to t = 0; then it closes at t = 0 and opens again at t = 105 µs. Find: 1. Ix(75 µs), 2. Vx(75 µs), 3. Ix(190 µs), 4. Vx(190 µs). Attached is the diagram of the circuit and its answers. so i understand how to get...

Homework Statement I have uploaded the questions in the attachment. I am having trouble with 2. e,f and 3.c untitled.png is the parts that I am having trouble with. untitled1.png and untitled2.png is the entire question. Homework Equations y(t)= steady state+transientThe Attempt at a Solution...

Homework Statement I would like to derive the equation Vc=Vss+(Vi-Vss)*e^(-t/RC) Vss is the steady state voltage Vi is the initial capacitor voltage Vc is the capacitor voltage The Attempt at a Solution I tried to find solution using laplace transform. E=iR+1/c∫idt. Taking laplace...

Why oscillations occur in transient response of a system ? Suppose transfer function of a system is 1/(s+1). Then its impulse response will be c(t)=e^{}-t . So why just we don't show only an exponential curve to graphically represent the impulse response, why we also show the oscillations ?