Control Lab (미완성)

Phase margin.

The phase margin is that amount of additional phase lag at the gain crossover frequency required to bring the system to the verge of instability. The gain crossover frequency is the frequency at which |G(jω)|, the magnitude of the open-loop transfer function, is unity. The phase margin γ is 180˚ plus the phase angle Φ of the open-loop transfer function at the gain crossover frequency, of γ = 180˚ + Φ

 

Gain margin.

The gain margin is the reciprocal of the magnitude |G(jω)| at the frequency at which the phase angle is -180˚. Defining the phase crossover frequency ω₁ to be the frequency at which the phase angle of the open-loop transfer function equals -180˚ gives the gain margin Kg=1/|G(jω₁)|.

 

Zero-Order Hold block

The Zero-Order Hold block holds its input for the sample period you specify. The block accepts one input and generates one output. Each signal can be scalar or vector. If the input is a vector, the block holds all elements of the vector for the same sample period. In order to convert an input signal with a continuous sample time to an output signal with a discrete sample time.

 

The DC gain is obtained by dividing the steady state value of the output by the magnitude of the input step.