Ziegler-Nichols, Cohen-Coon и реакционная кривая
Цель: Изучить тему «Ziegler-Nichols, Cohen-Coon и реакционная кривая» и закрепить её практическими заданиями и самопроверкой.
2 акад. часа чтение и разбор теории, решение задач, работа со схемой или виртуальным стендом и проверка понимания.
Основной материал
Classical methods provide starting tuning from process response. Ziegler-Nichols has open-loop reaction curve and closed-loop ultimate gain variants. Cohen-Coon uses model parameters and is aimed at first-order-plus-dead-time type processes.
Not magic constants
Classical tuning often aggressive. Results require validation under real constraints, valve limits, noise and safety. Modern practice may use IMC/lambda tuning or vendor autotuners for more robust response.
Практическая работа
Given model K, tau, theta instructor provides formula table. Calculate initial PI settings and simulate. Then reduce aggressiveness and compare overshoot. (Formula table should be supplied by LMS/lab sheet to avoid memorizing constants.)
Самопроверка
• What data uses reaction curve?
• What is ultimate gain concept?
• Are classical settings final?
• Why aggressive tuning problematic?
• What should be validated after tuning?
Что нужно запомнить
- Classical methods provide starting tuning from process response.
- Ziegler-Nichols has open-loop reaction curve and closed-loop ultimate gain variants.
- Cohen-Coon uses model parameters and is aimed at first-order-plus-dead-time type processes.
- Results require validation under real constraints, valve limits, noise and safety.
- Modern practice may use IMC/lambda tuning or vendor autotuners for more robust response.