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1

Possibly this is a slightly old question... An "introduction to control theory" course sounds unlikely to cover this stuff, but one of the control courses in the Masters' year I'm in right now includes topics that might be of interest to you: Convex optimisation Semi-definite programming to guarantee stability Distributed algorithms (most ...


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Find the transfer function $\delta_r(t)\to \psi (t)$ and $\delta _r(t)\to \beta (t)$. Divide the first transfer function by the second to get the transfer function $\beta (t)\to \psi (t)$. These calculations can be tedious. I used Mathematica to get the following result. ssm = StateSpaceModel[{p'[t] == -11.450 p[t] + 2.7185 r[t] - 19.4399 \[Beta][t] + ...


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Why dont you construct a state-space model from the given equations (which happen to be in the appropriate form) and either continue using the state space model or convert it to a transfer function in matlab. A continuous-time state-space model looks like this: $$\dot{x} = Ax + Bu$$ $$y = Cx+Du$$ Where $x$ and $u$ are vectors and $A$ and $B$ matrices. $$\...


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Your systems shows extremely close pole-zero cancellation. So much even that it nearly removes 4 poles and zeros. Lets look at why, starting with the Bode plot: The magnitude plot is constantly decreasing with a slope of -40dB/decade. Following basic rules this already implies that at the given frequencies, the system can be approximated using a double ...


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It all boils down to the numbers. The constants in your TF basically seem to describe an integrator with some "disturbance" somewhere in the frequency. The easy way for the whole clear picture is factorise both numerator and denominator to see where poles and zeros are. Your graphs being able to show them depends on the scale limits you set and on ...


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NOT AN ANSWER This is not an answer, its more a praise to an unsung facet of the genius of a much celebrated architect. The title of the question (minus the word control) reminded me of an experience I wanted to share (which is relevant is a very generic way). When I visited Barcelona (sometime in the previous millennium), I had already a few years of ...


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H-infinity control uses just as any other controller the outputs to compute a new input. Internally, it does store some kind of linear combination of previous outputs and inputs that assure the resulting control signal stabilizes the system and achieves the control goal. This can be compared to how a LQR + Observer works, the observer estimates something ...


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The most precise way to control flow is with valves/flow regulator. The main problem is the cost. Although, its a very basic component and its not too costly if you have too many outlets the cost will pile up. Even if you had matching orifices, you might have issues with the pressure drop inside the pipes and corners. Another way to control the flow would ...


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One basic way is to adjust the valves, the dry ones fully open and the ones bleeding all the pressure just slightly open, or even restricted permanently by a smaller size bushing just before the valve. In conjunction with that, you can install a water tank between the pump and your network with an adequate head and a hydraulic actuator to stop the tank's ...


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You are allowed to claim 2 BPCS IPL's but not from the same BPCS, eg you will need a PLC and a DCS with an IPL in each to claim both of them, plus they must be adequately independent. Additionally, you will be capped at a RRF of 10 for each, giving 100 for both, but that could be the difference between a SIL 3 SIF and a SIL 1 SIF in the SIS, potentially.


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A transfer function of a closed-loop feedback control system is written in the form: $$ T(s) = \frac{H(s)}{G(s)} $$ where $G(s)$ is called the characteristic polynomial of the system. The poles and zeros of the system are defined: Zeros $\rightarrow$ Roots of $H(s)$ Poles $\rightarrow$ Roots of $G(s)$ The stability of the closed-loop system can be ...


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Creating an output from 2 inputs won't have more precision; it will have 2 sources of error. If you are trying to control relative humidity, then using that as your control variable only makes sense.


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