# Eigenvalue for DC motor convergence rate

#### pcming

Hi,
I have troubles solving this question:
Given the general DC motor governed equation, find the control voltage such that the speed w tends to constand reference input w* and the convergence rate is determined by the desired eigenvalues L1 and L2.
I think it's easy to find the control voltage to the speed w. However I don't know how to find "convergence rate" which is determined by the desired eigenvalues. Can anyone give me some suggestions? Thanks.

#### Andrew Mason

Homework Helper
pcming said:
Hi,
I have troubles solving this question:
Given the general DC motor governed equation, find the control voltage such that the speed w tends to constand reference input w* and the convergence rate is determined by the desired eigenvalues L1 and L2.
I think it's easy to find the control voltage to the speed w. However I don't know how to find "convergence rate" which is determined by the desired eigenvalues. Can anyone give me some suggestions? Thanks.
Can you give us the "general DC motor governed equation"?

AM

#### pcming

Hi Andrew,
here it is:

J(dw/dt)=K1*i-T
L(di/dt)=-R*i-K2*w+u

where J is the inertial moment, w is motor speed, T is load torque, R is resistance, i is current, K1 and K2 are constant, and u is the input voltage.

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