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    Control Systems Engineering - Block Reduction Help

    Homework Statement Hello, I'm trying to reduce the following block diagram Homework Equations The Attempt at a Solution I appear to be having some issues in doing this. The first thing that I did to reduce this block diagram was to take the forward path that has 2/(s+4) with negative...
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    Autocorrelation Function of a Signal

    I actually didn't know this E[F(f(t))F(g(t))] = E[F(t)F(g(t) -f(t))] = R_{FF}(g(t) - f(t))? If I were to try and find the power spectral density of X(t) I would make use of S_{XX}(f) = F[R_{XX}(\tau)]. Were F[] is the Fourier Transform. S_{XX}(f) = F[2*delta(\tau) - delta(\tau - 1) -...
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    Autocorrelation Function of a Signal

    Hey MathematicalPhysicist, Thanks for the reply. I didn't realize this was so simple. My new attempt at a solution I know that . But I don't understand how this equation is true . It reminds of the simple fact that if LHS = RHS LHS + 1 = RHS +1 But that doesn't seem to be the case here...
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    Autocorrelation Function of a Signal

    Homework Statement I'm posting this question here at this point. I am having difficulty understanding autocorrelation in terms of solving the problem below. I don't seem to understand the math behind this. A white noise process W(t) with unity (N_0/2 = 1) power spectral density is input to a...
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    Engineering Simple Circuit Problem (Clarification of doubts)

    The value for I_x doesn't seem to be correct. I'm not exactly sure how you got the value that you did. The node to the left of the 5 ohm resistor there's only three paths for current to flow through. It looks like your summing the currents at node A when you solve for Ix? If this is the case...
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    Engineering Simple Circuit (RL circuit)

    What about the voltage across the inductor?
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    Engineering Simple Circuit Problem (Clarification of doubts)

    When you did your conversion, point B shouldn't be connected to ground, it wasn't in the original problem before the conversion.
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    Engineering Simple Circuit (RL circuit)

    I would recommend not memorizing such equations. It really makes things complicated when presented with problems that don't fit them. There are several ways you could solve the problem. Do you know the equation for KVL for after the switch is opened?
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    Digital Communication Systems - Autocorrelation

    Homework Statement A white noise process W(t) with unity (N_0/2 = 1) power spectral density is input to a linear system. The output of the linear system is X(t), where X(t) = W(t) - W(t - 1) Determine the autocorrelation of X(t) and sketch it. Homework Equations Let τ denote a time...
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    Article that Explains IGBT well

    Hi, I'm an undergraduate EE major and am having trouble understanding IGBT. I understand the basic principle, a PNP transistor in ? (forgot the name) configuration with a MOSFET with a parasitic NPN transistor. I understand that it's a 4 layered device. I however think I would struggle trying...
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    Electrical Engineering - Control Systems - Design Via Frequency Respon

    My text says that we can find the frequency, ω_{max} at which the maximum phase angle, Θ_{max}, occurs ω_{max} = \frac{1}{T\sqrt{β}} But this doesn't really seem to help since I don't know the frequency ω_{max}, unless it's the bandwidth frequency ω_{BW}, which I don't think it is. My text...
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    Electrical Engineering - Control Systems - Design Via Frequency Respon

    For a lead network G_{c}(s) = \frac{1}{β}\frac{s + \frac{1}{T}}{s + \frac{1}{βT}} I'm still unsure where \frac{1}{\sqrt{2}} came from though. There's a standard representation for the compensator C(s)? Edit 1: From the characteristic equation 1 + kG(s)C(s) = 0 kG(s)C(s) = -1 kG(s) = -...
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    Electrical Engineering - Control Systems - Design Via Frequency Respon

    done editing Homework Statement I'm given the following transfer function that represents a physical apparatus G(s) = \frac{X(s)}{F(s)} = \frac{3.333*10^{4}}{s^{2}} I'm asked to design a lead compensator to achieve closed-loop stability. The requirements are that it must have a transient...
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    Combined Translational & Rotational System Transfer Function

    Thanks for your response. Should this go in the advanced physics forum? This question is actually from a control systems class, but I posted it in the physics forums because I'm having a hard time understanding the physics behind this problem, especially the free body diagram. I was able to...
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    Combined Translational & Rotational System Transfer Function

    Homework Statement I'm given the following diagram And asked to find the transfer function G(s) = \frac{X(s)}{T(s)} and seem to be having some difficulty doing so. Homework Equations The Attempt at a Solution Apparently this is free body diagram I seem to be having difficulty...
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    Electrical Engineering - Control Systems - 2cnd Order System

    Homework Statement Given a electrical circuit as one below One can find the transfer function For second order systems this can be written as I know that the damping coefficient can be found using the following formula In the over damped case ζ>1 can easily occur depending on the...
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    Control Systems Engineering - Signal Flow Graphs

    Hi, I seem to be having some issues going from state space representation of a system to signal flow graph representation. My troubles seem to be, if I have something like this \frac{d}{dt}x_{1}(t) = v_{1}(t) In state space representation I list functions to which the derivatives are as...
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    Digital Logic - Tri State Buffers

    Homework Statement I'm trying to implement the function F = A'BC+ABD+AB'D' using 3 tri-state buffers. Apparently I'm supposed to connect the buffers together and use C, D, and D' as inputs to buffers. I'm supposed to pass A and B through logic to get the input signals. I'm supposed to...
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    Buck dc-dc Converter w/Control System Analysis

    Well you've stumped me to stay the least, and I'm a bit concerned by suggesting that the problem can't be solved I did not realize that I could think of the transistor and the diode as a switch. This may lead me in the right direction. I'm not exactly sure why it could be considered a switch...
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    Buck dc-dc Converter w/Control System Analysis

    Homework Statement I'm given the following circuit http://imageshack.com/a/img850/8576/b3ny.png [Broken] and given L, V_{in}, D, P_{o}, f_{s} and q(t). How do I go about finding T_{s}, V_{a}, i_{L}, i_{L} ripple, and I_{o}. Homework Equations The Attempt at a Solution I'm honestly not...
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    Control Systems Engineering - Masons Rule Help

    So if I wanted positive Vload/Idist it would just be the opposite magnitude, -1/(CFS)?
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    Simulink Help Drawing ODE

    Homework Statement Hi, I was wondering if someone could help me create a basic differential equation in Simulink. I'm trying to create the following equations http://imageshack.com/a/img197/1379/cic.PNG [Broken] I tried using this as an example...
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    Inverse Laplace Transform Help

    So if you have no idea what one of the functions in the frequency domain is and you get something like inverse Laplace transform( F(s)G(s) ) and you know what G(s) of is but F(s) is not given then you have no way to evaluate the expression?
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    Transfer Function to State Space Calculator Program

    Hi, Does anyone know a program that I can put on my TI-84 calculator that will allow me to input any transfer function and get the state space representation of the system or the other way around. For example G(s) = \frac{\sum(K_{i}s^{i})}{\sum(P_{i}s^{i})} The calculator prompts you...
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    Control Systems Engineering - Masons Rule Help

    Is it really just -\frac{C_{f}s}{1 - C_{f}s}?
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    Control Systems Engineering - Masons Rule Help

    Homework Statement I'm trying to find \frac{V_{Load}(s)}{I_{Dist}(s)} using Mason's rule. I was able to solve for \frac{V_{Load}}{I_{Cf}(S)} using Mason's rule but am not sure how to solve for \frac{V_{Load}(s)}{I_{Dist}(s)}. http://imageshack.com/a/img31/4299/zr5.PNG [Broken] Homework...
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    Inverse Laplace Transform Help

    Homework Statement Is there a way to evaluate L^{-1}(\frac{F(s)}{s + a})? I'm sure if it can be evaluate. Homework Equations The Attempt at a Solution
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    Engineering Transfer Function and State Space Analysis of Op-Amp circuit

    Homework Statement http://imagizer.imageshack.us/v2/800x600q90/690/0tab.png [Broken] [Broken] I'm asked to find the transfer function and then find the state space representation and seem to be stuck. Homework Equations The Attempt at a Solution My textbook states that for a...
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