Question

The steady-state error of a Type 1 system for a unit step input is:

• A. Zero
• B. Infinite
• C. A non-zero constant
• D. Oscillatory

Hint:

Type 1 system → zero steady-state error for step input.

Answer 1

The Correct Option is A

Concept: System type is defined by number of poles at origin.
• Type 0 → finite error for step
• Type 1 → zero error for step
• Type 2 → zero error for step and ramp

Step 1: Unit step input \[ R(s) = \frac{1}{s} \]

Step 2: Error formula \[ e_{ss} = \frac{1}{1 + K_p} \] For Type 1 system: \[ K_p = \infty \] \[ e_{ss} = 0 \] \[ \therefore \text{Correct answer is (A)} \]