$K_p=1.2\,\tau/(K\cdot L),\quad T_i=2L,\quad T_d=0.5L$
Adjust proportional gain Kp, integral time Ti and derivative time Td. Compare step responses, controller output, overshoot, time to 90% and IAE for first-order, delayed, second-order and integrating plants.
TRY THE SAME CONDITIONS
Start with the default first-order plant: process gain 1, time constant 5s, Kp=1, Ti=5s, Td=0s, setpoint 1 and duration 50s. Time to 90% is about 11.5s and IAE about 4.99. Change only Kp first and compare both response and controller output.
Calculator ↑The basic form is u=Kp(e+∫e dt/Ti+Td·de/dt); parallel gains are Ki=Kp/Ti and Kd=Kp·Td. The implementation uses a 0.02s time step, derivative filtering and output limits of ±10. The tank demonstration has independent controls.
For fixed Kp, Ki=Kp/Ti decreases as Ti increases. Use the explicit Disable integral action checkbox to turn I off completely; the P preset checks it. The independent tank illustration disables I at its maximum Ti of 40s.
Rise time means first arrival at 90% of the target, not 10–90%. Settling time is the first sample after the last excursion outside ±2%, provided every remaining sample stays inside. A final sample outside gives —. End-of-run error is a finite-time value, not necessarily steady-state error.
It proposes starting values, with assumed delay for some models and limits to the input ranges. It does not guarantee optimality or physical-plant stability. Check saturation, controller output and response.
Not directly. PID form, units, sample time, noise and actuator constraints must match. This page compares simplified models and cannot write settings to equipment.
Theory reference (not certification of this tool)
MathWorks: PID formsExplanation updated: 6 September 2026