# Questions tagged [control-theory]

The tag has no usage guidance.

22 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
435 views

### Connection between PID, Pole placement and LQR

I am trying to control a wheeled inverted pendulum with a PID controller. I already designed a linear quadratic regulator (LQR) and a pole placement regulator (PPR). I would like to design a PID ...
62 views

### From where does State space model equations come from?

I have a good basic understanding on classical control theory. Now I am studying modern control theory.I encountered the following equations as seen below. Online I have only been able to find ...
52 views

### fast analytical technique identifying poles/zeros using degree of freedom

I encounter some engineers who can quickly spot poles and zeros in the circuit by identifying "degree of freedom". For example, a typical technical discussion goes like : "a miller ...
50 views

67 views

### Digital PLL reference noise rejection

I have a fully digital implementation of a PLL. The problem that I have is the white noise coming from the PFD (you can view it as input jitter). I would like to filter it a lot, but an implementation ...
118 views

### a linear system is a bilinear transformation of anyone its circuit elements

I am reading about dissection theorem and the part below is a bit confusing. Could anyone one explain it? Any transfer function of a linear system is a bilinear transformation of anyone its ...
49 views

### Decide P controller gain K so that phase margin is 50 deg

I need help finding the gain $K$ so that the phase margin for the system equals 50 degrees. $$F(s) = K$$ $$G(s) = \dfrac{1}{(s+1)^2}$$ $v$ is a process disturbance sinusoid with amplitude 2.5 and ...
44 views

### Determine range of proportional gain with given overshoot

I have given the open-loop transfer function $$G_{ol} = 1.42 \frac{(s+3)^2+6^2}{(s-1)(s+2)((s+4)^2+4^2)}$$ The task I was given is determining the range of the proportional gain, which makes the ...
119 views

### What will be minimum number of states / state variables for these control systems in state-space model?

Consider the systems as LTI and SISO with transfer functions given below: I have read that minimum number of states for an LTI SISO system required to represent in state space analysis for any ...
155 views

### 555 square wave generation with frequency feedback

Knowing that 555's behaviour varies according to temperature, I wondered: In an astable configuration, is there some way to measure output frequency, compare it with some desired value, and use this ...
126 views

### Transfer function with separate time delays in each term

We've been given the problem below for our current assignment As far as I can recall, I have never seen a transfer function with time units in the function itself, added onto each separate term. I ...
259 views

### Op-amp control theory

back at it again trying to use your genius brains. I have been trying to teach myself audio amplifier design. The big road block I am getting into is the control theory part of it, meaning how does ...
62 views

### Obtaining the analytical expression using the state transformation matrix

I am trying to derive the analytical expression in the box below. T is the state transformation matrix. x_dot=A*x(t) is a second order linear system. A has 2 distinct eigenvalues s1 and s2 and ...
331 views

### Why gain crossover frequency must be lower than phase crossover frequency for stable systems?

As far as I understood from here, phase margin means the amount of phase that needs to be added in order to coincide with 0 db gain and -180 degrees phase. Likewise for the gain margin it means means ...
144 views

### Tips for solving difficult block diagrams?

I've gotten the hang of solving block diagrams, i.e. condensing them to a transfer function. I'm aware that one may be solved in multiple ways. For simple diagrams, it's fairly straightforward to see ...
74 views

### Design controller to get this response

We have the following closed loop system where a is from 1 to 10 and p from 0 to 1(excluding 1). We want to design controllers H(s) and C(s) so that the step response is inside this area This is ...
470 views

### Calculate K for best settling time?

I'm practising on compensators and the root locus. A very common problem in my textbook is to find the value of a variable for the minimum settling time of the system. I have no trouble drawing the ...
I have only seen systems with this transfer function treated in stability criteria with this general form:$$\frac{KG(s)}{1\pm KG(s)}$$ so the $$\lvert H(s)\rvert =1$$ is it possible to apply criteria ...